Title: Theory / Important / CS / Programming / Objective-C / Library / UIKit / View / General
Tags: constant automatedNewLineAfterCommaSpace

Typ: UIView
Meaning: An object that manages the content for a rectangular area on the screen.
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/Introduction/Introduction.html
https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Context: iOS
Name: View

Instruction: [view setNeedsDisplay]
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/Introduction/Introduction.html
Effect: invalidate view's snapshot and ensure it's recomputed asap
Language: Objective-C
Context: iOS
Variables: UIView view

Constant: UIViewContentModeCenter
Meaning: The option to center the content in the view’s bounds, keeping the proportions the same.
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: Objective-C
Context: iOS

Constant: UIViewContentModeScaleAspectFill
Meaning: ?
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: Objective-C

Constant: UIViewContentModeScaleAspectFit
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: Objective-C

Constant: UIViewContentModeScaleToFill
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: Objective-C

Constant: UIViewContentModeRedraw
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: Objective-C

Name: Stretching area
Definition: The part of the view that gets resized when the view size change
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Context: View

Variable: view.contentStretch
Meaning: The part of the view that gets resized when the view size change
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Context: View
Language: Objective-C

Variable: view.frame
Meaning: position and size changes for the view.
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Context: View
Language: Objective-C

Variable: view.bounds
Meaning: size of the view
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Context: View
Language: Objective-C

Variable: view.center
Meaning: The center point of the view's frame rectangle.
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: View
Language: Objective-C
Typ: CGPoint
Variables: UIView view

Variable: view.transform
Meaning: rotate or scale the view
the transform applied to the view, relative to the center of its bounds.
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Typ: CGAffineTransform
Variables: UIView view

Variable: view.alpha
Meaning: transparency of the view
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Context: View
Language: Objective-C

Variable: view.backgroundColor
Meaning: background color of the view
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Context: View
Language: Objective-C

Variable: view.contentStretch
Meaning: view's content stretch
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Context: View
Language: Objective-C

Question: where is the coordinate (0,0) in UIKit
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Context: IOs

Name: Current transformation matrix
Definition: the affine transform in use at any given time
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Context: View
Abbreviation: CTM

Question: Coordinate uses which units
Answer: Points, measured with floats,
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Context: View

Instruction: [window
  addSubview:view
]
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Effect: add view to window
Language: Objective-C
Variables: UIWindow window

Variable: window.windowLevel
Meaning: How that window is positioned relative to other windows
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Context: UIView
Language: ObjectiveC

Instruction: high windowLevel
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Effect: Mean that the window is above the normal window, e.g. status bar, warning
Language: ObjectiveC
Context: UIView

Constant: UIWindowDidBecomeVisibleNotification
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: ObjectiveC
Context: UIView

Constant: UIWindowDidBecomeHiddenNotification
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: ObjectiveC
Context: UIView

Constant: UIWindowDidBecomeKeyNotification
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: ObjectiveC
Context: UIView

Constant: UIWindowDidResignKeyNotification
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: ObjectiveC
Context: UIView

Name: The key window
Definition: The window that receive keystrokes
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Context: UIView

Variable: view.autoresizingMask
Meaning: how a view responds to changes in its parent view's bounds
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: ObjectiveC
Variables: UIView view

Variable: view.autoresiweSubviews
Meaning: whether the current view's subviews are resized at all
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: ObjectiveC
Variables: UIView view

Variable: view.contentMode, view.contentStretch
Meaning: how the content is treated when the view's width or height changes
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: ObjectiveC
Variables: UIView view

Variable: view.tag
Meaning: some number uniquely identifying this vuew
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: ObjectiveC
Variables: UIView view

Instruction: [UIView
  viewWithTag:n
]
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Language: ObjectiveC
Returns: the view with tag n
Variables: UIView view

Instruction: [view
  bringSubviewToFront:subview
]
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Effect: move subviewTo front
Language: ObjectiveC
Variables: UIView view

Instruction: [view
  bringSubviewToBack:subview
]
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Effect: move subviewTo back of the list of subview of view
Language: ObjectiveC
Variables: UIView view

Instruction: [view removeFromSuperview]
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Effect: remove this view from superview
Language: ObjectiveC
Variables: UIView view

Instruction: [view
  exchangeSubviewAtIndex:n
  withSubviewAtIndex:m
]
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Effect: exchanges subviews at indexes n and m
Language: ObjectiveC
Variables: UIView view

Name: A hidden view
Definition: A view with proprety hidden set to YES or alpha set to 0.0
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Context: UIView

Instruction: [view
  insertSubview:newSubview
  aboveSubview:someSubview
]
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Effect: insert newSubview above someSubview in the list of subviews of view
Language: Objective-C
Variables: UIView view

Instruction: [view
  insertSubview:newSubview
  belowSubview:someSubview
]
Page: https://developer.apple.com/library/archive/documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html
Effect: insert newSubview below someSubview in the list of subviews of view
Language: Objective-C
Variables: UIView view

Instruction: [view
  grey_saveCurrentAlphaAndUpdateWithValue:alpha]
Page: https://github.com/google/EarlGrey/blob/earlgrey2/CommonLib/Additions/UIView+GREYCommon.h
Effect: Sets the view's alpha value to the provided alpha value, storing the current value so it can be restored using UIView::grey_restoreAlpha.
Language: objective-C

Instruction: [view
  grey_restoreAlpha]
Page: https://github.com/google/EarlGrey/blob/earlgrey2/CommonLib/Additions/UIView+GREYCommon.h
Effect: Quick check to see if a view meets the basic visibility criteria of being not hidden, visible with a minimum alpha and has a valid accessibility frame. It also checks to ensure if a view is not a subview of another view or window that has a translucent alpha value or is hidden.
Language: objective-C

Instruction: [view
  grey_isAncestorOfView:specifiedView]
Page: https://github.com/google/EarlGrey/blob/earlgrey2/CommonLib/Additions/UIView+GREYCommon.h
Language: objective-C
Returns: Whether the current view is an ancestor of the specified view.

Instruction: [view
  grey_keepSubviewOnTopAndFrameFixed:specifiedView]
Page: https://github.com/google/EarlGrey/blob/earlgrey2/CommonLib/Additions/UIView+GREYCommon.h
Effect: Makes sure that subview view is always on top, even if other subviews are added in front of it. Also keeps the view's frame fixed to the current value so parent can't change it.
Language: objective-C

Instruction: [view
  grey_recursivelyMakeOpaque]
Page: https://github.com/google/EarlGrey/blob/earlgrey2/CommonLib/Additions/UIView+GREYCommon.h
Effect: Makes this view and all its super view opaque.
Language: objective-C
Extra: Successive calls to this method will replace the previously stored alpha value, causing any saved value to be lost.

Instruction: [view
  grey_restoreOpacity]
Page: https://github.com/google/EarlGrey/blob/earlgrey2/CommonLib/Additions/UIView+GREYCommon.h
Effect: Restores the opacity of this view and it's super views if they were made opaque by calling -[UIView grey_recursivelyMakeOpaque].
Language: objective-C
Extra: If -[UIView grey_recursivelyMakeOpaque] was not called before, then this method will perform a no-op on each of the view's superviews.

Instruction: [view
  grey_bringAlwaysTopSubviewToFront]
Page: https://github.com/google/EarlGrey/blob/earlgrey2/CommonLib/Additions/UIView+GREYCommon.h
Effect: Makes sure that subview view is always on top is added to the front of all other subviews.
Language: objective-C

Instruction: [viewController
  setNeedsStatusBarAppearanceUpdate
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Indicates to the system that the view controller status bar attributes have changed.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  setNeedsTouchBarUpdate
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Tells the system to update the Touch Bar.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  addKeyCommand:keyCommand
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Associates the specified keyboard shortcut with the view controller.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  removeKeyCommand:keyCommand
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Removes the key command from the view controll
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  setEditing:editing animated:animated
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Sets whether the view controller shows an editable view.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  didReceiveMemoryWarning
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Sent to the view controller when the app receives a memory warning.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  didReceiveMemoryWarning:coder
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Encodes state-related information for the view controller.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  decodeRestorableStateWithCoder:coder
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Decodes and restores state-related information for the view controller.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  applicationFinishedRestoringState
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Called on restored view controllers after other object decoding is complete
Language: Objective-C
Variables: UIViewController viewController
Abbreviation: After other object decoding has completed, the system calls this method. This allows a view controller to complete setup after other state restoration, relying on the system to ensure that the states of all objects from the restoration archive have been decoded.

Instruction: [viewController
  contentScrollViewForEdge
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: ?
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  setContentScrollView:scrollView
  forEdge:edge
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: ?
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  initWithNibName:nibNameOrNil
  bundle:nibBundleOrNil
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Returns: A newly initialized UIViewController object from nib objects
Variables: UIViewController viewController

Instruction: [viewController
  initWithCoder:coder
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Creates a view controller with data in an unarchiver.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  loadView
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Creates the view that the controller manages.
Language: Objective-C
Variables: UIViewController viewController
Assuming: Don't call directly. It's called when view controller request the view property

Instruction: [viewController
  viewDidLoad
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Called after the controller's view is loaded into memory.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  loadViewIfNeeded
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Loads the view controller’s view if it has not yet been loaded.
Language: Objective-C
Variables: UIViewController viewController
Extra: Calling this method loads the view controller’s view from its storyboard file, or creates the view as needed based on the established rules.

Instruction: [viewController
  viewWillAppear:animated
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Notifies the view controller that its view is about to be added to a view hierarchy. If YES, the view is being added to the window using an animation.
Language: Objective-C
Variables: UIViewController viewController
Extra: Discussion
This method is called before the view controller's view is about to be added to a view hierarchy and before any animations are configured for showing the view. You can override this method to perform custom tasks associated with displaying the view. For example, you might use this method to change the orientation or style of the status bar to coordinate with the orientation or style of the view being presented. If you override this method, you must call super at some point in your implementation.
For more information about the how views are added to view hierarchies by a view controller, and the sequence of messages that occur, see Supporting Accessibility.
Note
If a view controller is presented by a view controller inside of a popover, this method is not invoked on the presenting view controller after the presented controller is dismissed.

Instruction: [viewController
  viewDidAppear:animated
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Notifies the view controller that its view was added to a view hierarchy.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  viewWillDisappear:animated
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Notifies the view controller that its view is about to be removed from a view hierarchy.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  viewDidDisappear:animated
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Notifies the view controller that its view was removed from a view hierarchy.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  viewSafeAreaInsetsDidChange
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Called to notify the view controller that the safe area insets of its root view changed.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  viewWillLayoutSubviews
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Called to notify the view controller that its view is about to layout its subviews.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  viewDidLayoutSubviews
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Called to notify the view controller that its view has just laid out its subviews.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  updateViewConstraints
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Called when the view controller's view needs to update its constraints.
Language: Objective-C
Variables: UIViewController viewController

Question: When is it okay to override updateViewConstraints
Answer: changing constraints in place is too slow
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Chapter: Objective-C
Variables: UIViewController viewController
Answer2: a view is producing an umber of redundant change
Answer3: You must call [super updateViewConstraints] at the end

Question: What to do when you need to change the set of constraints
Answer: Only changes the constraints actually changed. Do NOT deactivate all to reactivate the one you want
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Chapter: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  shouldPerformSegueWithIdentifier:identifier
  sender:sender
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Determines whether the segue with the specified identifier should be performed.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  prepareForSegue:segue
  sender:sender
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Notifies the view controller that a segue is about to be performed.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  targetViewControllerForAction:action
  sender:sender
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Returns: the view controller that responds to the action or nil
Variables: UIViewController viewController

Instruction: [viewController
  collapseSecondaryViewController:secondaryViewController
  forSplitViewController:splitViewController
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Called when a split view controller transitions to a compact-width size class.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  separateSecondaryViewControllerForSplitViewController:splitViewController
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Called when a split view controller transitions to a regular-width size class.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController setNeedsUserInterfaceAppearanceUpdate]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Notifies the view controller that a change occurred that might affect the preferred interface style.
Availability
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  addChildViewController:childController
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Adds the specified view controller as a child of the current view controller.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  removeFromParentViewController
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Removes the view controller from its parent.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController transitionFromViewController:fromViewController
  toViewController:toViewController
  duration:duration
  options:options
  animations:animations
  completion:completion
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Transitions between two of the view controller's child view controllers.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  beginAppearanceTransition:isAppearing
  animated:animated
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Tells a child controller its appearance is about to change.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  endAppearanceTransition]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Tells a child controller its appearance has changed.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  setOverrideTraitCollection:collection
  forChildViewController:childViewController
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Changes the traits assigned to the specified child view controller.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  overrideTraitCollectionForChildViewController:childViewController
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Returns: Retrieves the trait collection for a child view controller.
Variables: UIViewController viewController

Instruction: [viewController
  willMoveToParentViewController:parent
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Called just before the view controller is added or removed from a container view controller.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  didMoveToParentViewController:parent
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Called after the view controller is added or removed from a container view controller.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  setToolbarItems:toolbarItems
  animated:animated
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Sets the toolbar items to be displayed along with the view controller.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  setNeedsUpdateOfScreenEdgesDeferringSystemGestures:gestures
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Notifies the system of changes to the screen edges that defer system gestures.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  setNeedsUpdateOfHomeIndicatorAutoHidden]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Notifies UIKit that your view controller updated its preference regarding the visual indicator for returning to the Home screen.
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  setNeedsUpdateOfPrefersPointerLocked]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Indicates that the view controller changed the pointer lock preference.
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.childViewControllerForTouchBar
Meaning: The child view controller that the system uses to display content in the Touch Bar.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.performsActionsWhilePresentingModally
Meaning: Whether the view controller performs menu-related actions.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController
Initialization: YES

Variable: viewController.editing
Meaning: whether the view controller currently allows the user to edit the view contents.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Name: An edit-done button
Definition: A button "edit" if the view is editable, and "done" otherwise
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Chapter: Objective-C
Variables: UIViewController viewController

Variable: viewController.editButtonItem
Meaning: a bar button item that toggles its title and associated state between Edit and Done.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.restorationIdentifier
Meaning: The identifier that determines whether the view controller supports state restoration.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.restorationClass
Meaning: The class responsible for recreating this view controller when restoring the app's state.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.focusGroupIdentifier
Meaning: ?
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.sheetPresentationController
Meaning: The sheet presentation controller for the view controller.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.storyboard
Meaning: The storyboard from which the view controller originated or nil
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.nibName
Meaning: The name of the view controller's nib file, if one was specified.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.nibBundle
Meaning: The view controller's nib bundle if it exists.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.view
Meaning: The view that the controller manages. (lazy. Uses loadView on first access)
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController
Initialization: nil

Variable: viewController.viewIfLoaded
Meaning: The view if it's loaded. Nil otherwise
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.viewLoaded
Meaning: Whteher the view is loaded
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.title
Meaning: A localized string that represents the view this controller manages.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.preferredContentSize
Meaning: The preferred size for the view controller’s view.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: CGSize
Variables: UIViewController viewController

Variable: viewController.beingDismissed
Meaning: whether the view controller is being dismissed.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.beingPresented
Meaning: whether the view controller is being presented.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.movingFromParentViewController
Meaning: whether the view controller is being removed from a parent view controller.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.movingToParentViewController
Meaning: whether the view controller is being moved to a parent view controller.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.additionalSafeAreaInsets
Meaning: Custom insets that you specify to modify the view controller's safe area.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.viewRespectsSystemMinimumLayoutMargins
Meaning: whether the view controller's view uses the system-defined minimum layout margins.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.systemMinimumLayoutMargins
Meaning: The minimum layout margins for the view controller's root view.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.edgesForExtendedLayout
Meaning: The edges that you extend for your view controller.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: UIRectEdge
Variables: UIViewController viewController
Initialization: UIRectEdgeAll All edges of the rectangle.

Variable: viewController.extendedLayoutIncludesOpaqueBars
Meaning: whether or not the extended layout includes opaque bars.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController
Initialization: NO

Variable: viewController.shouldAutorotate
Meaning: whether the view controller's contents should autorotate.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.supportedInterfaceOrientations
Meaning: The interface orientations that the view controller supports.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: UIInterfaceOrientationMask
Variables: UIViewController viewController
Initialization: UIInterfaceOrientationMaskAll for the iPad idiom and UIInterfaceOrientationMaskAllButUpsideDown for the iPhone idiom
Assuming: Not 0

Variable: viewController.preferredInterfaceOrientationForPresentation
Meaning: The interface orientation to use when presenting the view controller.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Variable: viewController.modalPresentationStyle
Meaning: The presentation style for modal view controllers.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: UIModalPresentationStyle
Variables: UIViewController viewController
Initialization: UIModalPresentationAutomatic
Assuming: Only used in regular-width size classes

Typ: UIModalPresentationStyle
Meaning: Modal presentation styles available when presenting view controllers.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewController viewController

Constant: UIModalPresentationAutomatic
Meaning: The default presentation style chosen by the system.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Context: UIModalPresentationStyle

Question: What modal presentation sheet is used for UIModalPresentationAutomatic
Answer: For most view controllers, UIKit maps this style to the UIModalPresentationPageSheet style, but some system view controllers may map it to a different style.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Variables: UIViewController viewController

Constant: UIModalPresentationNone
Meaning: no adaptations should be made.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Context: UIModalPresentationStyle

Constant: UIModalPresentationFullScreen
Meaning: the presented view covers the screen
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Context: UIModalPresentationStyle

Constant: UIModalPresentationCurrentContext
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Context: UIModalPresentationStyle

Constant: UIModalPresentationCustom
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Context: UIModalPresentationStyle

Constant: UIModalPresentationOverFullScreen
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Context: UIModalPresentationStyle

Constant: UIModalPresentationOverCurrentContext
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Context: UIModalPresentationStyle

Constant: UIModalPresentationPopover
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Context: UIModalPresentationStyle
Assuming: Parametrized by popoverPresentationController

Constant: UIModalPresentationBlurOverFullScreen
Meaning: style that blurs the underlying content before displaying new content in a full-screen presentation.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Context: UIModalPresentationStyle

Variable: viewController.modalTransitionStyle
Meaning: The transition style to use when presenting the view controller.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: UIModalTransitionStyle
Variables: UIViewControler viewController
Initialization: UIModalTransitionStyleCoverVertical

Constant: UIModalTransitionStyleCoverVertical
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: UIModalTransitionStyle

Constant: UIModalTransitionStyleFlipHorizontal
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: UIModalTransitionStyle

Constant: UIModalTransitionStyleCrossDissolve
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: UIModalTransitionStyle

Constant: UIModalTransitionStylePartialCurl
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Assuming: the parent view controller is presenting a full-screen view and you use the UIModalPresentationFullScreen modal presentation style.
Typ: UIModalTransitionStyle

Variable: viewController.modalInPresentation
Meaning: whether the view controller enforces a modal behavior
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController
Initialization: NO

Variable: viewController.definesPresentationContext
Meaning: whether this view controller's view is covered when the view controller or one of its descendants presents a view controller.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController
Initialization: NO

Variable: viewController.providesPresentationContextTransitionStyle
Meaning: whether the view controller specifies the transition style for view controllers it presents.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController
Initialization: NO

Variable: viewController.disablesAutomaticKeyboardDismissal
Meaning: whether the current input view is dismissed automatically when changing controls.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController
Initialization: Yes only for UIModalPresentationFormSheet. Otherwise NO

Variable: viewController.transitioningDelegate
Meaning: The delegate object that provides transition animator, interactive controller, and custom presentation controller objects.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.transitionCoordinator
Meaning: the transition coordinator object of the closest view controller in "presentation" or "dismissal"
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.presentationController
Meaning: The presentation controller that’s managing the current view controller.
Depending of modalPresentationStyle, create it if it does not exists, otherwise nil
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.popoverPresentationController
Meaning: The nearest popover presentation controller that is managing the current view controller.
If it does not exists, in UIModalPresentationPopover creates it, otherwise nil
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.restoresFocusAfterTransition
Meaning: whether an item that previously was focused should again become focused when the item's view controller becomes visible and focusable.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.overrideUserInterfaceStyle
Meaning: The user interface style adopted by the view controller and all of its children.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: UIUserInterfaceStyle
Variables: UIViewControler viewController

Variable: viewController.preferredUserInterfaceStyle
Meaning: The preferred interface style for this view controller.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: UIUserInterfaceStyle
Variables: UIViewControler viewController

Variable: viewController.childViewControllerForUserInterfaceStyle
Meaning: The default value of this property is nil. A container view controller can override this property and return the child view controller that supports the currently preferred user interface style, as determined by the preferredUserInterfaceStyle property.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.childViewControllers
Meaning: An array of view controllers that are children of the current view controller. It contains no presented view controllers.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController
Extra: This property is only intended to be read by an implementation of a custom container view controller.

Variable: viewController.shouldAutomaticallyForwardAppearanceMethods
Meaning: whether appearance methods are forwarded to child view controllers.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.presentingViewController
Meaning: The view controller that presented this view controller or its ancestor modally. Otherwise nil
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.presentedViewController
Meaning: The view controller that is presented by this view controller, or one of its ancestors in the view controller hierarchy. Or Nil
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.parentViewController
Meaning: The parent view controller of the recipient or nil
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.splitViewController
Meaning: The nearest ancestor in the view controller hierarchy that is a split view controller or nil
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.navigationController
Meaning: The nearest ancestor in the view controller hierarchy that is a navigation controller or nil
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.tabBarController
Meaning: The nearest ancestor in the view controller hierarchy that is a tab bar controller or nil
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.navigationItem
Meaning: The navigation item used to represent the view controller in a parent's navigation bar. Created on first access.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: UINavigationItem
Variables: UIViewControler viewController
Initialization: a navigation item that displays the view controller's title.

Variable: viewController.hidesBottomBarWhenPushed
Meaning: whether the toolbar at the bottom of the screen is hidden when the view controller is pushed on to a navigation controller.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.toolbarItems
Meaning: The UIBarButtonItems to display in the navigation controller's toolbar if any
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.tabBarItem
Meaning: The tab bar item that represents the view controller when added to a tab bar controller.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController
Assuming: child of a tab bar controller

Variable: viewController.extensionContext
Meaning: The extension context containing this view controller, or nil
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: NSExtensionContext
Variables: UIViewControler viewController

Variable: viewController.preferredScreenEdgesDeferringSystemGestures
Meaning: The screen edges for which you want your gestures to take precedence over the system gestures
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Question: Which view is in charge of gesture from edge?
Answer: System usually
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Variables: UIViewControler viewController

Question: How a view can take charge of screen-edge gesture
Answer: Change preferredScreenEdgesDeferringSystemGestures then call setNeedsUpdateOfScreenEdgesDeferringSystemGestures
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Variables: UIViewControler viewController

Variable: viewController.childViewControllerForScreenEdgesDeferringSystemGestures
Meaning: the child view controller that should be queried to see if its gestures should take precedence.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.prefersHomeIndicatorAutoHidden
Meaning: whether the system is allowed to hide the visual indicator for returning to the Home screen.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController
Initialization: NO

Variable: viewController.childViewControllerForHomeIndicatorAutoHidden
Meaning: In a container, the child in charge of deciding whether one must display a visual indicator for returning to the home screen
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController
Initialization: nil

Variable: viewController.prefersPointerLocked
Meaning: whether the view controller prefers to lock the pointer to a specific scene.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController
Initialization: NO

Question: How to lock a pointer
Answer: scene must be full screen
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Variables: UIViewControler viewController
Answer2: The scene must be in the UISceneActivationStateForegroundActive state.
Answer3: prefersPointerLocked = YES
Answer4: setNeedsUpdateOfPrefersPointerLocked.

Variable: viewController.childViewControllerForPointerLock
Meaning: In a container, the child in charge of deciding whether pointer should be locked
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.childViewControllerForStatusBarHidden
Meaning: The view controller whose status bar hidden/unhidden status should be used or nil
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.childViewControllerForStatusBarStyle
Meaning: The view controller whose status bar style should be used or nil
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController

Variable: viewController.preferredStatusBarStyle
Meaning: The preferred status bar style for the view controller.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: UIStatusBarStyle
Variables: UIViewControler viewController

Variable: viewController.prefersStatusBarHidden
Meaning: whether the view controller prefers the status bar to be hidden or shown.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController
Extra: call the setNeedsStatusBarAppearanceUpdate method

Question: How can a view control whether status bar is hidden or not
Answer: In a container, uses childViewControllerForStatusBarHidden to let a child decide
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Variables: UIViewControler viewController
Answer2: Otherwise, change prefersStatusBarHidden and call setNeedsStatusBarAppearanceUpdate

Variable: viewController.modalPresentationCapturesStatusBarAppearance
Meaning: whether a view controller, presented non-fullscreen, takes over control of status bar appearance from the presenting view controller.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Variables: UIViewControler viewController
Initialization: NO

Variable: viewController.preferredStatusBarUpdateAnimation
Meaning: Specifies the animation style to use for hiding and showing the status bar for the view controller.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Typ: UIStatusBarAnimation
Variables: UIViewControler viewController

Instruction: [UIViewController
  attemptRotationToDeviceOrientation
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Attempts to rotate all windows to the orientation of the device.
Language: Objective-C
Variables: UIViewControler viewController

Instruction: [UIViewController
  allowedChildViewControllersForUnwindingFromSource:source
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: An array of view controllers representing the child view controllers to search for the destination of an unwind segue.
Language: Objective-C
Variables: UIViewControler viewController
Extra: Initialization: the contents of the childViewControllers property minus the view controller returned by the childViewControllerContainingSegueSource: method

Instruction: [UIViewController
  childViewControllerContainingSegueSource:source
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Returns: The child view controller that contains the source of the unwind segue.
Availability
Variables: UIViewControler viewController

Instruction: [UIViewController
  canPerformUnwindSegueAction:action
  fromViewController:fromViewController
  sender:sender]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Called on a view controller to determine whether it responds to an unwind action.
Language: Objective-C
Variables: UIViewControler viewController

Instruction: [UIViewController
  unwindForSegue:unwindSegue
  towardsViewController:subsequentVC
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Called when an unwind segue transitions to a new view controller.
Language: Objective-C
Variables: UIViewControler viewController

Instruction: [UIViewController
  showViewController:vc
  sender:sender
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Presents a view controller in a primary context.
Language: Objective-C
Variables: UIViewControler viewController
Extra: The default implementation of this method calls the targetViewControllerForAction:sender: method to locate an object in the view controller hierarchy that overrides this method.

Instruction: [UIViewController
  showDetailViewController:vc
  sender:sender
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Presents a view controller in a secondary context.
Language: Objective-C
Variables: UIViewControler viewController
Extra: The default implementation of this method calls the targetViewControllerForAction:sender: method to locate an object in the view controller hierarchy that overrides this method. It then calls the method on that target object, which displays the view controller in an appropriate way. If the targetViewControllerForAction:sender: method returns nil, this method uses the window’s root view controller to present vc modally.

Name: The safe area
Definition: the visible portion of the overall interface
Page: https://developer.apple.com/documentation/uikit/uiview/positioning_content_relative_to_the_safe_area?language=objc
Variables: iOS

Instruction: [viewController
  presentViewController:viewControllerToPresent
  animated:flag
  completion:completion
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Presents a view controller modally, then run completion
Language: Objective-C
Variables: UIViewController viewController

Instruction: [viewController
  dismissViewControllerAnimated:flag
  completion:completion
]
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Effect: Dismisses the view controller that was presented modally by the view controller then call completion
Language: Objective-C
Variables: UIViewController viewController

Constant: UIViewControllerShowDetailTargetDidChangeNotification
Meaning: Posted when a split view controller is expanded or collapsed.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C

Constant: UIViewControllerHierarchyInconsistencyException
Meaning: Raised if the view controller hierarchy is inconsistent with the view hierarchy.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C

Typ: UIActivityViewController
Meaning: A view controller that you use to offer standard services from your app.
Page: https://developer.apple.com/documentation/uikit/uiactivityviewcontroller?language=objc
Language: Objective-C
Subtype of: UIViewController

Question: Responsibilities of Views
Answer: Drawing
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Answer2: animation
Answer3: Layout and subview management
Answer4: Event handling

Name: A subview of view
Definition: A view nested in view
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Variables: UIView view

Name: A superview of v
Definition: The view in which v is nested
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Variables: UIView v

Question: Constraint on UIView
Answer: Most methods must be called on main thread
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Variables: UIView v

Question: When to subclass UIView
Answer: When the basic UIView classes and standard system do not provide the capabilities you need
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Variables: UIView v

Instruction: [UIView
  userInterfaceLayoutDirectionForSemanticContentAttribute:attribute
]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Returns: the user interface direction for the given semantic content attribute.
Variables: UIView v

Instruction: [UIView
 userInterfaceLayoutDirectionForSemanticContentAttribute:semanticContentAttribute
  relativeToLayoutDirection:layoutDirection
]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Returns: the layout direction implied by the specified semantic content attribute, relative to the specified layout direction.
Variables: UIView v

Instruction: [UIView
  animateWithDuration:duration
  delay:delay
  options:options
  animations:animations
  completion:completion
]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Effect: initiates a set of animations to perform on the view. The block object in the animations parameter contains the code for animating the properties of one or more views.
Language: Objective-C
Variables: UIView v

Instruction: [UIView
  animateWithDuration:duration
  animations:animations
  completion:completion
]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Effect: performs the specified animations immediately, then call completion
Language: Objective-C
Variables: UIView v

Instruction: [UIView
  animateWithDuration:duration
  animations:animations
]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Effect: performs the specified animations immediately
Language: Objective-C
Variables: UIView v

Instruction: [UIView
  transitionFromView:fromView
  toView:toView
  duration:duration
  options:options
  completion:completion
]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Effect: Creates a transition animation between the specified views using the given parameters.
Language: Objective-C
Variables: UIView v

Instruction: [UIView
  animateKeyframesWithDuration:duration
  delay:delay
  options:options
  animations:animations
  completion:completion
]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Effect: Creates an animation block object that can be used to set up keyframe-based animations for the current view.
Language: Objective-C
Variables: UIView v

Instruction: [UIView
  animateKeyframesWithRelativeStartTime:frameStatTime
  relativeDuration:frameDuration
  animations:animations
]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Effect: Specifies the timing and animation values for a single frame of a keyframe animation.
Language: Objective-C
Variables: UIView v

Instruction: [UIView
  performSystemAnimation:animation
  onViews:views
  options:options
  animations:animations
  completion:completion
]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Effect: Performs a specified system-provided animation on one or more views, along with optional parallel animations that you define.
Language: Objective-C
Variables: UIView v

Instruction: [UIView
  animateWithDuration:duration
  delay:delay
  usingSpringWithDamping:dampingRatio
  initialSpringVelocity:velocity
  options:options
  animations:animations
  completion:completion
]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Effect: Performs a view animation using a timing curve corresponding to the motion of a physical spring.
Language: Objective-C
Variables: UIView v

Instruction: [UIView
  performWithoutAnimation:actionsWithoutAnimation
]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Effect: Disables a view transition animation.
Language: Objective-C
Variables: UIView v

Instruction: [UIView
  modifyAnimationsWithRepeatCount:count
  autoreverses:autoreverse
  animations:animations
]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Effect: Repeats the specified animations count times,  running the animation forward and backward if autoreverse.
Language: Objective-C
Variables: UIView v

Constant: UIViewContentMode(Top|Bottom|)(Left|Right|)
Meaning: Option to align the content on the top|bottom left|right
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C

Typ: UIInteraction
Meaning: protocol that an interaction implements to access the view that owns it.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C

Variable: interaction.view
Meaning: The view that owns the interaction.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Variables: UIInteraction interaction

Instruction: [interaction
  didMoveToView:view]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Effect: Tells the interaction that a view added or removed it from the view's interactions array.
Language: Objective-C
Variables: UIInteraction interaction

Instruction: [interaction
  willMoveToView:view]
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Effect: Tells the interaction that a view will add or remove it from the view's interactions array.
Language: Objective-C
Variables: UIInteraction interaction

Typ: UIViewAnimationCurve
TypMeaning: Specifies the supported animation curves.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Value: UIViewAnimationCurveEaseInOut
An ease-in ease-out curve causes the animation to begin slowly, accelerate through the middle of its duration, and then slow again before completing. This is the default curve for most animations.
Value2: UIViewAnimationCurveEaseIn
An ease-in curve causes the animation to begin slowly, and then speed up as it progresses.
Value3: UIViewAnimationCurveEaseOut
An ease-out curve causes the animation to begin quickly, and then slow down as it completes.
Value4: UIViewAnimationCurveLinear
A linear animation curve causes an animation to occur evenly over its duration.

Typ: UIViewAnimationOptions TODO
Meaning: Options for animating views using block objects.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C

Typ: UIViewAnimationTransition
TypMeaning: Animation transition options for use in an animation block object.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Value: UIViewAnimationTransitionNone
The option for indicating that no transition is specified.
Value2: UIViewAnimationTransitionFlipFrom(Left|Right)
A transition that flips a view around a vertical axis from (left to right|right to left).
The (left|right) side of the view moves towards the front and (right|left) side towards the back.
Value3: UIViewAnimationTransitionCurl(Up|Down)
A transition that curls a view (up|down) from the (bottom|top).

Typ: UISystemAnimation
TypMeaning: Option to remove the views from the hierarchy when animation is complete.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Value: UISystemAnimationDelete
Option to remove views from the view hierarchy when animation is complete.

Typ: UIViewKeyframeAnimationOptions TODO
Meaning: Key frame animation options used with the animateKeyframesWithDuration:delay:options:animations:completion: method.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C

Typ: UILayoutConstraintAxis
TypMeaning: Keys that specify a horizontal or vertical layout constraint between objects.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Value: UILayoutConstraintAxis(Horizontal|Vertical)
The constraint applied when laying out the (horizontal|vertical) relationship between objects.

Typ: UIViewTintAdjustmentMode
TypMeaning: The tint adjustment mode for the view.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Value: UIViewTintAdjustmentModeAutomatic
The tint adjustment mode of the view is the same as its superview’s tint adjustment mode (or UIViewTintAdjustmentModeNormal if the view has no superview).
Value2: UIViewTintAdjustmentModeNormal
The view's tintColor property returns the completely unmodified tint color of the view.
Value3: UIViewTintAdjustmentModeDimmed
The view's tintColor property returns a desaturated, dimmed version of the view's original tint color.

Constant: UILayoutFittingCompressedSize
Meaning: The option to use the smallest possible size.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Typ: CGSize

Constant: UILayoutFittingExpandedSize
Meaning: The option to use the largest possible size.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Typ: CGSize

Constant: UIViewNoIntrinsicMetric
Meaning: The absence of an intrinsic metric for a given numeric view property.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Typ: CGFloat

Typ: UIViewAutoresizing
TypMeaning: Options for automatic view resizing.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Value: UIViewAutoresizingNone
The option for indicating that the view does not resize.
Value2: UIViewAutoresizingFlexible(Left|Right|Top|Bottom)Margin
Resizing performed by expanding or shrinking a view in the direction of the (left|right|top|bottom) margin.
Value3: UIViewAutoresizingFlexible(Width|Heigh)
Resizing performed by expanding or shrinking a view's (width|height).

Typ: UISemanticContentAttribute
TypMeaning: A semantic description of the view’s contents, used to determine whether the view should be flipped when switching between left-to-right and right-to-left layouts.
Page: https://developer.apple.com/documentation/uikit/uiview?language=objc
Language: Objective-C
Value: UISemanticContentAttributeUnspecified
The default value for views. The view is flipped when switching between left-to-right and right-to-left layouts.
Value2: UISemanticContentAttributePlayback
A view representing the playback controls, such as Play, Rewind, or Fast Forward buttons or playhead scrubbers. These views are not flipped when switching between left-to-right and right-to-left layouts.
Value3: UISemanticContentAttributeSpatial
A view representing a directional control, such as a segment control for text alignment, or a D-pad control for a game. These views are not flipped when switching between left-to-right and right-to-left layouts.
Value4: UISemanticContentAttributeForce(LeftToRight|RightToLeft)
A view that is always displayed using a left-to-right|right-to-left layout.

Name: Layout margin
Definition: a visual buffer between a view’s content and any content outside of the view’s bounds
Page: https://developer.apple.com/documentation/uikit/uiview/positioning_content_within_layout_margins?language=objc

Name: Auto-layout
Definition: dynamically calculates the size and position of all the views in your view hierarchy, based on constraints placed on those views and updated based on internal and external changes
Page: https://developer.apple.com/documentation/uikit/uiview/positioning_content_within_layout_margins?language=objc

Question: The kinds of constraints
Answer: the space between views,
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Answer2: align the edge of views,
Answer3: define the relative size of two views, or
Answer4: even define a view’s aspect ratio.

Name: The priority of a constraint
Definition: How important the constraint is
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI

Name: The leading of the view
Definition: The left|right side of the view in left-to-right|right-to-left language. I.e. side where text start.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Variables: UIView view
Context: iOS UI

Name: The trailing of the view
Definition: The right|left side of the view in left-to-right|right-to-left language. I.e. side where text ends.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Variables: UIView view
Context: iOS UI

Variable: view.backgroundColor
Meaning: The view’s background color.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIColor
Variables: UIView view
Initialization: nil = transparent

Variable: view.hidden
Meaning: whether the view is hidden.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: NO

Variable: view.alpha
Meaning: the view (and subview) alpha value
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.opaque
Meaning: whether the view is opaque. (Hint to the drawign system)
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: YES

Variable: view.tintColor
Meaning: The first nondefault tint color value in the view’s hierarchy, ascending from and starting with the view itself.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIColor
Variables: UIView view
Extra: Clal tintColorDidChange after changing it
If the view’s tintAdjustmentMode property’s value is UIViewTintAdjustmentModeDimmed, then the tintColor property value is automatically dimmed.

Variable: view.tintAdjustmentMode
Meaning: The first non-default tint adjustment mode value in the view’s hierarchy, ascending from and starting with the view itself.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIViewTintAdjustmentMode
Variables: UIView view

Variable: view.clipsToBounds
Meaning: whether subviews are confined to the bounds of the view.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: NO

Variable: view.clearsContextBeforeDrawing
Meaning: whether the view’s bounds should be automatically cleared before drawing.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: YES

Variable: view.maskView
Meaning: An optional view whose alpha channel is used to mask a view’s content.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.layerClass
Meaning: the class used to create the layer for instances of this class.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.layer
Meaning: The view’s Core Animation layer used for rendering.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: CALayer not-nil
Variables: UIView view
Extra: The actual class of the object is determined by the value returned in the layerClass property. The view is the layer’s delegate.

Variable: view.userInteractionEnabled
Meaning: whether user events are ignored and removed from the event queue.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: YES

Variable: view.multipleTouchEnabled
Meaning: whether the view receives more than one touch at a time. Otherwise receive only the first touch
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: NO

Variable: view.exclusiveTouch
Meaning: whether the receiver block the delivery of touch events to other views in the same window
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: NO

Variable: view.frame
Meaning: The frame rectangle, which describes the view’s location and size in its superview’s coordinate system.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: CGRect
Variables: UIView view
Assuming: transform property is the identity transform

Variable: view.bounds
Meaning: The bounds rectangle, which describes the view’s location and size in its own coordinate system.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: Origin (0,0) and same size as the rectangle in view.frame

Variable: view.transform3D
Meaning: The three-dimensional transform to apply to the view.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: CATransform3D
Variables: UIView view
Initialization: CATransform3DIdentity

Variable: view.superview
Meaning: The receiver’s superview, or nil if it has none.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.subviews
Meaning: The receiver’s immediate subviews.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.window
Meaning: The receiver’s window object, or nil if it has none.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIWindow
Variables: UIView view

Variable: view.directionalLayoutMargins
Meaning: The default spacing to use when laying out content in a view, taking into account the current language direction.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: NSDirectionalEdgeInsets
Variables: UIView view

Variable: view.layoutMargins
Meaning: The default spacing to use when laying out content in the view.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIEdgeInsets
Variables: UIView view

Variable: view.preservesSuperviewLayoutMargins
Meaning: whether the current view also respects the margins of its superview.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: NO

Variable: view.safeAreaInsets
Meaning: The insets that you use to determine the safe area for this view.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIEdgeInsets
Variables: UIView view

Variable: view.safeAreaLayoutGuide
Meaning: The layout guide representing the portion of your view that is unobscured by bars and other content.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UILayoutGuide
Variables: UIView view

Variable: view.insetsLayoutMarginsFromSafeArea
Meaning: whether the view's layout margins are updated automatically to reflect the safe area.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: YES

Variable: view.constraints
Meaning: The constraints held by the view.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: NSArray<__kindof NSLayoutConstraint *>
Variables: UIView view

Variable: viewOrLayoutGuide.(bottom|center(X|Y)|leading|trailing|left|right|top)Anchor
Meaning: The anchor of the bottom, center in x/y, leading, trailing, left, right or top of the view
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: NSLayout(X|Y)AxisAnchor
Variables: UIView|UILayoutGuide viewOrLayoutGuide

Variable: view.(first|last)BaselineAnchor
Meaning: A layout anchor representing the baseline for the (top|bottomm)ost line of text in the view.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.(width|height)Anchor
Meaning: A layout anchor representing the width/height of the view’s frame.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: NSLayoutDimension
Variables: UIView view

Variable: view.layoutGuides
Meaning: The array of layout guide objects owned by this view.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: NSArray<__kindof UILayoutGuide *>
Variables: UIView view

Variable: view.layoutGuides
Meaning: A layout guide representing an area with a readable width within the view.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UILayoutGuide
Variables: UIView view

Variable: view.intrinsicContentSize
Meaning: The size that view have naturally given its content
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: CGSize
Variables: UIView view

Variable: view.alignmentRectInsets
Meaning: The insets from the view’s frame that define its alignment rectangle.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.viewFor(First|Last)BaselineLayout
Meaning: a view that contains the first|last row of text
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Extra: Used for NSLayoutAttribute(First|Last)Baseline

Variable: viewOrLayoutGuide.hasAmbiguousLayout
Meaning: whether the constraints impacting the layout of the view incompletely specify the location of the view.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView|UILayoutGuide viewOrLayoutGuide

Variable: view.autoresizesSubviews
Meaning: whether the receiver automatically resizes its subviews when its bounds change.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: YES

Variable: view.autoresizingMask
Meaning: how the receiver resizes itself when its superview’s bounds change.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.requiresConstraintBasedLayout
Meaning: whether the receiver depends on the constraint-based layout system.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.translatesAutoresizingMaskIntoConstraints
Meaning: whether the view’s autoresizing mask is translated into Auto Layout constraints.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.overrideUserInterfaceStyle
Meaning: The user interface style adopted by the view and all of its subviews.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIUserInterfaceStyle
Variables: UIView view

Variable: view.semanticContentAttribute
Meaning: A semantic description of the view’s contents, used to determine whether the view should be flipped when switching between left-to-right and right-to-left layouts.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UISemanticContentAttribute
Variables: UIView view

Variable: view.effectiveUserInterfaceLayoutDirection
Meaning: The user interface layout direction appropriate for arranging the immediate content of the view.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIUserInterfaceLayoutDirection
Variables: UIView view
Extra: note that you can’t assume that the value propagates through the view’s subtree.

Variable: viewOrLayoutGuide.keyboardLayoutGuide
Meaning: A layout guide that tracks the keyboard’s position in your app’s layout.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIKeyboardLayoutGuide
Variables: UIView|UILayoutGuide viewOrLayoutGuide

Variable: view.(min|max)imumContentSizeCategory
Meaning: ?
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIContentSizeCategory
Variables: UIView view

Variable: view.focusGroupPriority
Meaning: ?
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIFocusGroupPriority
Variables: UIView view

Variable: view.focusEffect
Meaning: ?
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIFocusEffect
Variables: UIView view

Variable: view.appliedContentSizeCategoryLimitsDescription
Meaning: ?
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: NSString
Variables: UIView view

Variable: view.showsLargeContentViewer
Meaning: whether to show the view in the large content viewer.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.scalesLargeContentImage
Meaning: whether the large content viewer scales the item’s image to a larger size.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.largeContentTitle
Meaning: describes the view in the large content viewer.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.largeContentImageInsets
Meaning: Insets to adjust the position of the view’s image so it appears centered in the large content viewer.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIEdgeInsets
Variables: UIView view

Variable: view.largeContentImage
Meaning: An image that represents the view in the large content viewer.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Typ: UIImage
Variables: UIView view

Variable: view.accessibilityIgnoresInvertColors
Meaning: whether the view ignores an accessibility request to invert its colors.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.tag
Meaning: An integer that you can use to identify view objects in your application.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: 0

Variable: view.restorationIdentifier
Meaning: The identifier that determines whether the view supports state restoration.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: nil
Assuming: If its set, owner and view contorller must also be restorable

Variable: view.motionEffects
Meaning: The array of motion effects for the view.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.focusGroupIdentifier
Meaning: The identifier of the focus group that this view belongs to.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.focused
Meaning: whether the item is currently focused.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.inheritedAnimationDuration
Meaning: the inherited duration of the current animation.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Assuming: only makes sens in the animation block

Variable: view.canBecomeFocused
Meaning: Whether the view is currently capable of being focused.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view
Initialization: NO

Question: why can a view not be focusable
Answer: canBecomeFocused = False
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Chapter: Objective-C
Variables: UIView view
Context: iOS UI
Answer2: view is hidden
Answer3: view's alpha is 0
Answer4: userInteractionEnabled = NO
Answer5: View is not currently in the view hierarchy

Variable: view.gestureRecognizers
Meaning: The gesture-recognizer objects currently attached to the view.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.contentScaleFactor
Meaning: The scale factor applied to the view to transform points into pixel.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Variable: view.interactions
Meaning: The array of interactions for the view.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Context: iOS UI
Language: Objective-C
Variables: UIView view

Typ: UIInteraction
Meaning: The protocol that an interaction implements to access the view that owns it.
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [[UIView alloc]
  initWithFrame:frame
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: a newly allocated view object with the specified frame rectangle.
Variables: UIView view

Instruction: [[UIView alloc]
  initWithCoder:coder
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: new view with Coder
Variables: UIView view

Instruction: [uiView
  addSubview:view
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Adds a view to the end of the receiver’s list of subviews.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  bringSubviewTo(Front|Back):view
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Moves view so that it appears on (top|behind) of its siblings.
Language: Objective-C
Context: iOS UI
Variables: UIView view
Assuming: view is a subview

Instruction: [uiView
  removeFromSuperview
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Unlinks the view from its superview and its window, and removes it from the responder chain. removes any constraints that refer to the view you are removing, or that refer to any view in the subtree of the view you are removing.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  insertSubview:view
  atIndex:index
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Inserts view at the index.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  insertSubview:view
  (above|below)Subview:siblingSubview
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Inserts view (above|below) siblingSubview
Language: Objective-C
Context: iOS UI
Variables: UIView view
Assuming: siblingSubview is a view

Instruction: [uiView
  insertSubviewAtIndex1
  withSubviewAtIndex:index2
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Exchange the subviews at indices index1 and index2
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  isDescendantOfView:view
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Whether uiViwe is a descendant of view
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  didAddSubview:subview
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Tells uiView that a subview was added
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  willRemoveSubview:subview
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Tells uiView that a subview will be removed
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  willMoveToSuperview:newSuperview
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Tells uiView that it will move to newSuperview
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  didMoveToSuperview
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Tells uiView that it superview just changed
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  willMoveToWindow:newWindow
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Tells uiView that its window object is about to change to newWindow
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  didMoveToWindow
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Tells uiVew that its window object changed.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  layoutMarginsDidChange
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Notifies uiView that the layout margins changed.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  safeAreaInsetsDidChange
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Notifies uiView that its safe area changed
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  addConstraint(|s):constraint(|s)
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Add constraint(|s) to uiView
Language: Objective-C
Context: iOS UI
Variables: UIView view
Assuming: The constraint consider uiView or its subviews

Instruction: [uiView
  removeConstraint(|s):constraint(|s)
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Remove constraint(|s) to uiView , ignore the one it does not owns
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  addLayoutGuide:layoutGuide
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Adds layoutGuide to uiView.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  removeLayoutGuide:layoutGuide
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: remove layoutGuide to uiView.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  systemLayoutSizeFittingSize:targetSize
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: the optimal size of the view based on its current constraints.
Variables: UIView view

Instruction: [uiView
  systemLayoutSizeFittingSize:targetSize
  withHorizontalFittingPriority:verticalFittingPriority
  verticalFittingPriority:verticalFittingPriority
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: the optimal size of the view based on its constraints and the specified fitting priorities.
Variables: UIView view
Typ: CGSize

Instruction: [uiView
  invalidateIntrinsicContentSize
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Invalidates the view’s intrinsic content size.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  contentCompressionResistancePriorityForAxis:axis
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: the priority with which a view resists being made smaller than its intrinsic size.
Variables: UIView view

Instruction: [uiView
  setContentCompressionResistancePriority:priority
  forAxis:axis
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Sets the priority with which a view resists being made smaller than its intrinsic size.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  contentHuggingPriorityForAxis:axis
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: the priority with which a view resists being made larger than its intrinsic size.
Variables: UIView view
Typ: UILayoutPriority

Instruction: [uiView
  setContentHuggingPriority:priority
  forAxis:axis
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Sets the priority with which a view resists being made larger than its intrinsic size.
Language: Objective-C
Context: iOS UI
Variables: UIView view
Typ: UILayoutPriority

Instruction: [uiView
  alignmentRectForFrame:frame
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: the view’s alignment rectangle for frame.
Variables: UIView view
Typ: UILayoutPriority

Instruction: [uiView
  frameForAlignmentRect:alignmentRect
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: the view’s frame for a given alignment rectangle.
Variables: UIView view

Instruction: [uiView
  needsUpdateConstraints
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: whether the view’s constraints need updating.
Variables: UIView view

Instruction: [uiView
  setNeedsUpdateConstraints
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Call this method after having updated constraints
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  updateConstraints
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Override this method to optimize changes to your constraints.
Language: Objective-C
Context: iOS UI
Variables: UIView view
Extra: Call [super updateConstraints] as the final step in your implementation.
Assuming: override this method when changing constraints in place is too slow, or when a view is producing a number of redundant changes. Otherwise directly do the change

Instruction: [uiView
  updateConstraintsIfNeeded
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Updates the constraints for the receiving view and its subviews.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [viewOrLayoutGuide
  constraintsAffectingLayoutForAxis:axis
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: the constraints impacting the layout of the view for a given axis.
Variables: UIView|UILayoutGuide viewOrLayoutGuide
Assuming: This method should only be used for debugging constraint-based layout. No application should ship with calls to this method as part of its operation.

Instruction: [uiView
  exerciseAmbiguityInLayout
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Randomly changes the frame of a view with an ambiguous layout between the different valid values.
Language: Objective-C
Context: iOS UI
Variables: UIView view
Assuming: This method should only be used for debugging constraint-based layout. No application should ship with calls to this method as part of its operation.

Instruction: [uiView
  sizeThatFits:size
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: the size that best fits the specified size.
Variables: UIView view

Instruction: [uiView
  sizeToFit
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Resizes and moves the receiver view so it just encloses its subviews.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  layoutSubviews
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: uses any constraints you have set to determine the size and position of any subviews.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  setNeedsLayout
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Invalidates the current layout of the receiver and triggers a layout update during the next update cycle.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  layoutIfNeeded
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Lays out the subviews immediately, if layout updates are pending.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  (add|remove)Interaction:interaction
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Add|remove interaction to the view
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  drawRect:rect
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: draw uiView in the passed-in rect
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  setNeedsDisplay
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Marks the receiver’s entire bounds rectangle as needing to be redrawn.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  setNeedsDisplayInRect:rect
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Marks the receiver’s rect as needing to be redrawn.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  tintColorDidChange
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Called by the system when the tintColor property changes.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  viewPrintFormatter
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: a print formatter for the receiving view. or nil if the project can not be created
Variables: UIView view

Instruction: [uiView
  drawRect:rect
  forViewPrintFormatter:formatter
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Implemented to draw the view’s content for printing.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  (add|remove)GestureRecognizer:gestureRecognizer
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Add|remove gestureRecognizer to the view
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  gestureRecognizerShouldBegin:gestureRecognizer
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Asks the view if the gesture recognizer should be allowed to continue tracking touch events.
Language: Objective-C
Context: iOS UI
Returns: If the gesture recognizer should continue tracking touch events and use them to trigger a gesture.
Variables: UIView view

Instruction: [uiView
  (add|remove)MotionEffect:effect
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: (Begins|stop) applying a motion effect to the view.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  (encode|decode)RestorableStateWithCoder:coder
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: (Encodes|decode and restore) state-related information for the view.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: [uiView
  snapshotViewAfterScreenUpdatesXafterUpdates
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: a snapshot view based on the contents of the current view.
Variables: UIView view

Instruction: [uiView
  resizableSnapshotViewFromRect:recto
  afterScreenUpdates:afterUpdates
  withCapInsets:capInsets
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: a snapshot view based on the specified contents of the current view, with stretchable insets.
Variables: UIView view

Instruction: [uiView
  drawViewHierarchyInRect:rect
  afterScreenUpdates:afterUpdates
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Renders a snapshot of the complete view hierarchy as visible onscreen into the current context.
Language: Objective-C
Context: iOS UI
Returns: whether the snapshot is complete
Variables: UIView view

Instruction: [uiView
  viewWithTag:tag
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: the view whose tag matches the specified value.
Variables: UIView view

Instruction: [uiView
  convert(Point|Rect):pointInUIViewCoordinateSystem
  toView:view
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: Point|rect in view coordinate system
Variables: UIView view

Instruction: [uiView
  convert(Point|Rect):(point|rect)InFromViewCoordinateSystem
  fromView:fromView
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: (point|rect)InFromViewCoordinateSystem in uiView coordinate system
Variables: UIView view

Instruction: [uiView
  hitTest:point
  withEvent:event
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: the farthest descendant of the receiver in the view hierarchy (including itself) that contains a specified point and is visible, accepts interaction, has alpha>=0.01. Nil if point is outside the view hierarchy
Variables: UIView view

Instruction: [uiView
  pointInside:point
  withEvent:event
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Language: Objective-C
Context: iOS UI
Returns: Whether uiView contains point
Variables: UIView view

Instruction: [uiView
  endEditing:force
]
Page: https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
Effect: Causes the view (or one of its embedded text fields) to resign the first responder status.
Language: Objective-C
Context: iOS UI
Variables: UIView view

Instruction: UIContentSizeCategoryIsAccessibilityCategory(category)
Page: https://developer.apple.com/documentation/uikit/uitraitcollection?language=objc
Language: Objective-C
Returns: whether the content size category belongs to the group of accessibility-related sizes.

Instruction: UIContentSizeCategoryCompareToCategory(
  lhs,
  rhs
)
Page: https://developer.apple.com/documentation/uikit/uitraitcollection?language=objc
Language: Objective-C
Returns: whether they are equal or whether one is larger than the other.

Typ: UIDisplayGamut
TypMeaning: Constants that indicate the gamut of the current display.
Page: https://developer.apple.com/documentation/uikit/uitraitcollection?language=objc
Language: Objective-C
Value: UIDisplayGamutUnspecified
An unspecified gamut value.
Value2: UIDisplayGamutSRGB
The sRGB display gamut.
Value3: UIDisplayGamutP3
The P3 display gamut.

Typ: UIRectEdge
TypMeaning: Constants that specify the edges of a rectangle.
Page: https://developer.apple.com/documentation/uikit/uiviewcontroller?language=objc
Language: Objective-C
Value: UIRectEdgeNone
No edge.
Value2: UIRectEdgeTop|Left|Bottom|Right
The top|left|bottom|right edge of the rectangle.