PlatformViewFilter Class Reference

#import <FlutterPlatformViews_Internal.h>

Inheritance diagram for PlatformViewFilter:

Instance Methods
(instancetype)	- NS_UNAVAILABLE
(instancetype)	- initWithFrame:blurRadius:visualEffectView:
(void)	- updateVisualEffectView: [implementation]

Class Methods
(void)	+ resetPreparation
(void)	+ prepareOnce: [implementation]
(BOOL)	+ isUIVisualEffectViewImplementationValid [implementation]

Properties
CGRect	frame
CGFloat	blurRadius
UIVisualEffectView *	backdropFilterView
BOOL	backdropFilterViewConfigured [implementation]

Detailed Description

Definition at line 80 of file FlutterPlatformViews_Internal.h.

Method Documentation

initWithFrame:blurRadius:visualEffectView:

- (instancetype) initWithFrame:		(CGRect)	frame
blurRadius:		(CGFloat)	blurRadius
visualEffectView:		(UIVisualEffectView*)	NS_DESIGNATED_INITIALIZER

Definition at line 95 of file FlutterPlatformViews_Internal.mm.

                             :(CGRect)frame
                   blurRadius:(CGFloat)blurRadius
             visualEffectView:(UIVisualEffectView*)visualEffectView {
  if (self = [super init]) {
    _frame = frame;
    _blurRadius = blurRadius;
    [PlatformViewFilter prepareOnce:visualEffectView];
    if (![PlatformViewFilter isUIVisualEffectViewImplementationValid]) {
      FML_DLOG(ERROR) << "Apple's API for UIVisualEffectView changed. Update the implementation to "
                         "access the gaussianBlur CAFilter.";
      return nil;
    }
    _backdropFilterView = visualEffectView;
    _backdropFilterViewConfigured = NO;
  }
  return self;
}

isUIVisualEffectViewImplementationValid

+ (BOOL) isUIVisualEffectViewImplementationValid

implementation

Definition at line 95 of file FlutterPlatformViews_Internal.mm.

                                                {
  return _indexOfBackdropView > -1 && _indexOfVisualEffectSubview > -1 && _gaussianBlurFilter;
}

NS_UNAVAILABLE

- (instancetype) NS_UNAVAILABLE

prepareOnce:

+ (void) prepareOnce: (UIVisualEffectView*)  visualEffectView

implementation

Definition at line 95 of file FlutterPlatformViews_Internal.mm.

                   :(UIVisualEffectView*)visualEffectView {
  if (_preparedOnce) {
    return;
  }
  for (NSUInteger i = 0; i < visualEffectView.subviews.count; i++) {
    UIView* view = visualEffectView.subviews[i];
    if ([NSStringFromClass([view class]) hasSuffix:@"BackdropView"]) {
      _indexOfBackdropView = i;
      for (NSObject* filter in view.layer.filters) {
        if ([[filter valueForKey:@"name"] isEqual:@"gaussianBlur"] &&
            [[filter valueForKey:@"inputRadius"] isKindOfClass:[NSNumber class]]) {
          _gaussianBlurFilter = filter;
          break;
        }
      }
    } else if ([NSStringFromClass([view class]) hasSuffix:@"VisualEffectSubview"]) {
      _indexOfVisualEffectSubview = i;
    }
  }
  _preparedOnce = YES;
}

resetPreparation

+ (void) resetPreparation

Definition at line 95 of file FlutterPlatformViews_Internal.mm.

                         {
  _preparedOnce = NO;
  _gaussianBlurFilter = nil;
  _indexOfBackdropView = -1;
  _indexOfVisualEffectSubview = -1;
}

updateVisualEffectView:

- (void) updateVisualEffectView: (UIVisualEffectView*)  visualEffectView

implementation

Definition at line 95 of file FlutterPlatformViews_Internal.mm.

                              :(UIVisualEffectView*)visualEffectView {
  NSObject* gaussianBlurFilter = [_gaussianBlurFilter copy];
  FML_DCHECK(gaussianBlurFilter);
  UIView* backdropView = visualEffectView.subviews[_indexOfBackdropView];
  [gaussianBlurFilter setValue:@(_blurRadius) forKey:@"inputRadius"];
  backdropView.layer.filters = @[ gaussianBlurFilter ];
 
  UIView* visualEffectSubview = visualEffectView.subviews[_indexOfVisualEffectSubview];
  visualEffectSubview.layer.backgroundColor = UIColor.clearColor.CGColor;
  visualEffectView.frame = _frame;
 
  self.backdropFilterView = visualEffectView;
}

Property Documentation

backdropFilterView

- (UIVisualEffectView *) backdropFilterView

readnonatomicassign

Definition at line 95 of file FlutterPlatformViews_Internal.h.

backdropFilterViewConfigured

- (BOOL) backdropFilterViewConfigured

readwritenonatomicassignimplementation

Definition at line 79 of file FlutterPlatformViews_Internal.mm.

blurRadius

- (CGFloat) blurRadius

readnonatomicassign

Definition at line 89 of file FlutterPlatformViews_Internal.h.

frame

- (CGRect) frame

readnonatomicassign

Definition at line 84 of file FlutterPlatformViews_Internal.h.

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The documentation for this class was generated from the following files:

• shell/platform/darwin/ios/framework/Source/FlutterPlatformViews_Internal.h
• shell/platform/darwin/ios/framework/Source/FlutterPlatformViews_Internal.mm