FlutterPlatformViewsController Class Reference

#import <FlutterPlatformViewsController.h>

Inheritance diagram for FlutterPlatformViewsController:

Instance Methods
(instancetype)	- NS_DESIGNATED_INITIALIZER
(void)	- registerViewFactory:withId:gestureRecognizersBlockingPolicy:
	set the factory used to construct embedded UI Views. More...
(void)	- beginFrameWithSize:
	Mark the beginning of a frame and record the size of the onscreen. More...
(void)	- cancelFrame
	Cancel the current frame, indicating that no platform views are composited. More...
(void)	- prerollCompositeEmbeddedView:withParams:
	Record a platform view in the layer tree to be rendered, along with the positioning and mutator parameters. More...
(FlutterTouchInterceptingView *)	- flutterTouchInterceptingViewForId:
	Returns theFlutterTouchInterceptingView with the provided view_id. More...
(flutter::PostPrerollResult)	- postPrerollActionWithThreadMerger:
	Determine if thread merging is required after prerolling platform views. More...
(void)	- endFrameWithResubmit:threadMerger:
	Mark the end of a compositor frame. More...
(flutter::DlCanvas *)	- compositeEmbeddedViewWithId:
	Returns the Canvas for the overlay slice for the given platform view. More...
(void)	- reset
	Discards all platform views instances and auxiliary resources. More...
(BOOL)	- submitFrame:withIosContext:
	Encode rendering for the Flutter overlay views and queue up perform platform view mutations. More...
(void)	- onMethodCall:result:
	Handler for platform view message channels. More...
(long)	- firstResponderPlatformViewId
	Returns the platform view id if the platform view (or any of its descendant view) is the first responder. More...
(void)	- pushFilterToVisitedPlatformViews:withRect:
	Pushes backdrop filter mutation to the mutator stack of each visited platform view. More...
(void)	- pushVisitedPlatformViewId:
	Pushes the view id of a visted platform view to the list of visied platform views. More...
(size_t)	- embeddedViewCount
(UIView *_Nullable)	- platformViewForId:
(void)	- compositeView:withParams:
(const flutter::EmbeddedViewParams &)	- compositionParamsForView:
(std::vector< int64_t > &)	- previousCompositionOrder

Properties
const fml::RefPtr< fml::TaskRunner > &	taskRunner
	The task runner used to post rendering tasks to the platform thread. More...
UIView *_Nullable	flutterView
	The flutter view. More...
UIViewController< FlutterViewResponder > *_Nullable	flutterViewController
	The flutter view controller. More...

Detailed Description

Definition at line 30 of file FlutterPlatformViewsController.h.

Method Documentation

beginFrameWithSize:

- (void) beginFrameWithSize:

(SkISize)

frameSize

Mark the beginning of a frame and record the size of the onscreen.

Definition at line 409 of file FlutterPlatformViewsController.mm.

                          :(SkISize)frameSize {
  [self resetFrameState];
  self.frameSize = frameSize;
}

cancelFrame

- (void) cancelFrame

Cancel the current frame, indicating that no platform views are composited.

Additionally, reverts the composition order to its original state at the beginning of the frame.

Definition at line 414 of file FlutterPlatformViewsController.mm.

                    {
  [self resetFrameState];
}

compositeEmbeddedViewWithId:

- (DlCanvas *) FlutterPlatformViewsController:

(int64_t)

viewId

Returns the Canvas for the overlay slice for the given platform view.

Called from the raster thread.

Definition at line 645 of file FlutterPlatformViewsController.mm.

                                               :(int64_t)viewId {
  FML_DCHECK(self.slices.find(viewId) != self.slices.end());
  return self.slices[viewId]->canvas();
}

compositeView:withParams:

- (void) compositeView:		(int64_t)	viewId
withParams:		(const flutter::EmbeddedViewParams &)	params

Provided by category FlutterPlatformViewsController(Testing).

compositionParamsForView:

- (const EmbeddedViewParams& FlutterPlatformViewsController(Testing)):

(int64_t)

viewId

Provided by category FlutterPlatformViewsController(Testing).

embeddedViewCount

- (size_t) embeddedViewCount

Provided by category FlutterPlatformViewsController(Testing).

endFrameWithResubmit:threadMerger:

- (void) endFrameWithResubmit:		(BOOL)	shouldResubmitFrame
threadMerger:		(const fml::RefPtr<fml::RasterThreadMerger>&)	rasterThreadMerger

Mark the end of a compositor frame.

May determine changes are required to the thread merging state. Called from the raster thread.

Definition at line 423 of file FlutterPlatformViewsController.mm.

                            :(BOOL)shouldResubmitFrame
                threadMerger:(const fml::RefPtr<fml::RasterThreadMerger>&)rasterThreadMerger {
}

firstResponderPlatformViewId

- (long) firstResponderPlatformViewId

Returns the platform view id if the platform view (or any of its descendant view) is the first responder.

Returns -1 if no such platform view is found.

Definition at line 469 of file FlutterPlatformViewsController.mm.

                                     {
  for (auto const& [id, platformViewData] : self.platformViews) {
    UIView* rootView = platformViewData.root_view;
    if (rootView.flt_hasFirstResponderInViewHierarchySubtree) {
      return id;
    }
  }
  return -1;
}

flutterTouchInterceptingViewForId:

- (FlutterTouchInterceptingView *) flutterTouchInterceptingViewForId:

(int64_t)

viewId

Returns theFlutterTouchInterceptingView with the provided view_id.

Returns nil if there is no platform view with the provided id. Called from the platform thread.

Definition at line 462 of file FlutterPlatformViewsController.mm.

                                                                  :(int64_t)viewId {
  if (self.platformViews.empty()) {
    return nil;
  }
  return self.platformViews[viewId].touch_interceptor;
}

NS_DESIGNATED_INITIALIZER

- (instancetype) NS_DESIGNATED_INITIALIZER

onMethodCall:result:

- (void) onMethodCall:		(FlutterMethodCall*)	call
result:		(FlutterResult)	result

Handler for platform view message channels.

Definition at line 272 of file FlutterPlatformViewsController.mm.

                    :(FlutterMethodCall*)call result:(FlutterResult)result {
  if ([[call method] isEqualToString:@"create"]) {
    [self onCreate:call result:result];
  } else if ([[call method] isEqualToString:@"dispose"]) {
    [self onDispose:call result:result];
  } else if ([[call method] isEqualToString:@"acceptGesture"]) {
    [self onAcceptGesture:call result:result];
  } else if ([[call method] isEqualToString:@"rejectGesture"]) {
    [self onRejectGesture:call result:result];
  } else {
    result(FlutterMethodNotImplemented);
  }
}

References FlutterMethodNotImplemented.

platformViewForId:

- (UIView* _Nullable) platformViewForId:

(int64_t)

viewId

Provided by category FlutterPlatformViewsController(Testing).

postPrerollActionWithThreadMerger:

- (PostPrerollResult) FlutterPlatformViewsController:

(const fml::RefPtr<fml::RasterThreadMerger>&)

rasterThreadMerger

Determine if thread merging is required after prerolling platform views.

Called from the raster thread.

Definition at line 418 of file FlutterPlatformViewsController.mm.

                                                             :
    (const fml::RefPtr<fml::RasterThreadMerger>&)rasterThreadMerger {
  return flutter::PostPrerollResult::kSuccess;
}

prerollCompositeEmbeddedView:withParams:

- (void) prerollCompositeEmbeddedView:		(int64_t)	viewId
withParams:		(std::unique_ptr<flutter::EmbeddedViewParams>)	params

Record a platform view in the layer tree to be rendered, along with the positioning and mutator parameters.

Called from the raster thread.

Definition at line 436 of file FlutterPlatformViewsController.mm.

                                    :(int64_t)viewId
                          withParams:(std::unique_ptr<flutter::EmbeddedViewParams>)params {
  SkRect viewBounds = SkRect::Make(self.frameSize);
  std::unique_ptr<flutter::EmbedderViewSlice> view;
  view = std::make_unique<flutter::DisplayListEmbedderViewSlice>(viewBounds);
  self.slices.insert_or_assign(viewId, std::move(view));
 
  self.compositionOrder.push_back(viewId);
 
  if (self.currentCompositionParams.count(viewId) == 1 &&
      self.currentCompositionParams[viewId] == *params.get()) {
    // Do nothing if the params didn't change.
    return;
  }
  self.currentCompositionParams[viewId] = flutter::EmbeddedViewParams(*params.get());
  self.viewsToRecomposite.insert(viewId);
}

previousCompositionOrder

- (vector<int64_t>& FlutterPlatformViewsController(Testing)):

Provided by category FlutterPlatformViewsController(Testing).

pushFilterToVisitedPlatformViews:withRect:

- (void) pushFilterToVisitedPlatformViews:		(const std::shared_ptr<flutter::DlImageFilter>&)	filter
withRect:		(const SkRect&)	filterRect

Pushes backdrop filter mutation to the mutator stack of each visited platform view.

Definition at line 427 of file FlutterPlatformViewsController.mm.

                                        :(const std::shared_ptr<flutter::DlImageFilter>&)filter
                                withRect:(const SkRect&)filterRect {
  for (int64_t id : self.visitedPlatformViews) {
    flutter::EmbeddedViewParams params = self.currentCompositionParams[id];
    params.PushImageFilter(filter, filterRect);
    self.currentCompositionParams[id] = params;
  }
}

pushVisitedPlatformViewId:

- (void) pushVisitedPlatformViewId:

(int64_t)

viewId

Pushes the view id of a visted platform view to the list of visied platform views.

Definition at line 958 of file FlutterPlatformViewsController.mm.

                                 :(int64_t)viewId {
  self.visitedPlatformViews.push_back(viewId);
}

registerViewFactory:withId:gestureRecognizersBlockingPolicy:

- (void) registerViewFactory:		(NSObject<FlutterPlatformViewFactory>*)	factory
withId:		(NSString*)	factoryId
gestureRecognizersBlockingPolicy:		(FlutterPlatformViewGestureRecognizersBlockingPolicy)	gestureRecognizerBlockingPolicy

set the factory used to construct embedded UI Views.

Definition at line 399 of file FlutterPlatformViewsController.mm.

                           :(NSObject<FlutterPlatformViewFactory>*)factory
                              withId:(NSString*)factoryId
    gestureRecognizersBlockingPolicy:
        (FlutterPlatformViewGestureRecognizersBlockingPolicy)gestureRecognizerBlockingPolicy {
  std::string idString([factoryId UTF8String]);
  FML_CHECK(self.factories.count(idString) == 0);
  self.factories[idString] = factory;
  self.gestureRecognizersBlockingPolicies[idString] = gestureRecognizerBlockingPolicy;
}

reset

- (void) reset

Discards all platform views instances and auxiliary resources.

Called from the raster thread.

Definition at line 650 of file FlutterPlatformViewsController.mm.

              {
  // Reset will only be called from the raster thread or a merged raster/platform thread.
  // _platformViews must only be modified on the platform thread, and any operations that
  // read or modify platform views should occur there.
  fml::TaskRunner::RunNowOrPostTask(self.platformTaskRunner, [self]() {
    for (int64_t viewId : self.compositionOrder) {
      [self.platformViews[viewId].root_view removeFromSuperview];
    }
    self.platformViews.clear();
    self.previousCompositionOrder.clear();
  });
 
  self.compositionOrder.clear();
  self.slices.clear();
  self.currentCompositionParams.clear();
  self.viewsToRecomposite.clear();
  self.layerPool->RecycleLayers();
  self.visitedPlatformViews.clear();
}

submitFrame:withIosContext:

- (BOOL) submitFrame:		(std::unique_ptr<flutter::SurfaceFrame>)	frame
withIosContext:		(const std::shared_ptr<flutter::IOSContext>&)	iosContext

Encode rendering for the Flutter overlay views and queue up perform platform view mutations.

Called from the raster thread.

Definition at line 670 of file FlutterPlatformViewsController.mm.

                   :(std::unique_ptr<flutter::SurfaceFrame>)background_frame
     withIosContext:(const std::shared_ptr<flutter::IOSContext>&)iosContext {
  TRACE_EVENT0("flutter", "PlatformViewsController::SubmitFrame");
 
  // No platform views to render; we're done.
  if (self.flutterView == nil || (self.compositionOrder.empty() && !self.hadPlatformViews)) {
    self.hadPlatformViews = NO;
    return background_frame->Submit();
  }
  self.hadPlatformViews = !self.compositionOrder.empty();
 
  bool didEncode = true;
  LayersMap platformViewLayers;
  std::vector<std::unique_ptr<flutter::SurfaceFrame>> surfaceFrames;
  surfaceFrames.reserve(self.compositionOrder.size());
  std::unordered_map<int64_t, SkRect> viewRects;
 
  for (int64_t viewId : self.compositionOrder) {
    viewRects[viewId] = self.currentCompositionParams[viewId].finalBoundingRect();
  }
 
  std::unordered_map<int64_t, SkRect> overlayLayers =
      SliceViews(background_frame->Canvas(), self.compositionOrder, self.slices, viewRects);
 
  size_t requiredOverlayLayers = 0;
  for (int64_t viewId : self.compositionOrder) {
    std::unordered_map<int64_t, SkRect>::const_iterator overlay = overlayLayers.find(viewId);
    if (overlay == overlayLayers.end()) {
      continue;
    }
    requiredOverlayLayers++;
  }
 
  // If there are not sufficient overlay layers, we must construct them on the platform
  // thread, at least until we've refactored iOS surface creation to use IOSurfaces
  // instead of CALayers.
  [self createMissingOverlays:requiredOverlayLayers withIosContext:iosContext];
 
  int64_t overlayId = 0;
  for (int64_t viewId : self.compositionOrder) {
    std::unordered_map<int64_t, SkRect>::const_iterator overlay = overlayLayers.find(viewId);
    if (overlay == overlayLayers.end()) {
      continue;
    }
    std::shared_ptr<flutter::OverlayLayer> layer = self.nextLayerInPool;
    if (!layer) {
      continue;
    }
 
    std::unique_ptr<flutter::SurfaceFrame> frame = layer->surface->AcquireFrame(self.frameSize);
    // If frame is null, AcquireFrame already printed out an error message.
    if (!frame) {
      continue;
    }
    flutter::DlCanvas* overlayCanvas = frame->Canvas();
    int restoreCount = overlayCanvas->GetSaveCount();
    overlayCanvas->Save();
    overlayCanvas->ClipRect(flutter::ToDlRect(overlay->second));
    overlayCanvas->Clear(flutter::DlColor::kTransparent());
    self.slices[viewId]->render_into(overlayCanvas);
    overlayCanvas->RestoreToCount(restoreCount);
 
    // This flutter view is never the last in a frame, since we always submit the
    // underlay view last.
    frame->set_submit_info({.frame_boundary = false, .present_with_transaction = true});
    layer->did_submit_last_frame = frame->Encode();
 
    didEncode &= layer->did_submit_last_frame;
    platformViewLayers[viewId] = LayerData{
        .rect = overlay->second,  //
        .view_id = viewId,        //
        .overlay_id = overlayId,  //
        .layer = layer            //
    };
    surfaceFrames.push_back(std::move(frame));
    overlayId++;
  }
 
  auto previousSubmitInfo = background_frame->submit_info();
  background_frame->set_submit_info({
      .frame_damage = previousSubmitInfo.frame_damage,
      .buffer_damage = previousSubmitInfo.buffer_damage,
      .present_with_transaction = true,
  });
  background_frame->Encode();
  surfaceFrames.push_back(std::move(background_frame));
 
  // Mark all layers as available, so they can be used in the next frame.
  std::vector<std::shared_ptr<flutter::OverlayLayer>> unusedLayers =
      self.layerPool->RemoveUnusedLayers();
  self.layerPool->RecycleLayers();
 
  auto task = [self,                                                      //
               platformViewLayers = std::move(platformViewLayers),        //
               currentCompositionParams = self.currentCompositionParams,  //
               viewsToRecomposite = self.viewsToRecomposite,              //
               compositionOrder = self.compositionOrder,                  //
               unusedLayers = std::move(unusedLayers),                    //
               surfaceFrames = std::move(surfaceFrames)                   //
  ]() mutable {
    [self performSubmit:platformViewLayers
        currentCompositionParams:currentCompositionParams
              viewsToRecomposite:viewsToRecomposite
                compositionOrder:compositionOrder
                    unusedLayers:unusedLayers
                   surfaceFrames:surfaceFrames];
  };
 
  fml::TaskRunner::RunNowOrPostTask(self.platformTaskRunner, fml::MakeCopyable(std::move(task)));
 
  return didEncode;
}

References LayerData::rect.

Property Documentation

flutterView

- (UIView* _Nullable) flutterView

readwritenonatomicweak

The flutter view.

Definition at line 38 of file FlutterPlatformViewsController.h.

flutterViewController

- (UIViewController<FlutterViewResponder>* _Nullable) flutterViewController

readwritenonatomicweak

The flutter view controller.

Definition at line 41 of file FlutterPlatformViewsController.h.

taskRunner

- (const RefPtr<) fml:

readwritenonatomicassign

The task runner used to post rendering tasks to the platform thread.

Definition at line 35 of file FlutterPlatformViewsController.h.

---

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

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