Attach and position embedded UIVIews (flutter/engine#6614)

engine/src/flutter/flow/embedded_views.h

@@ -6,11 +6,15 @@
 #define FLUTTER_FLOW_EMBEDDED_VIEWS_H_
 
 #include "flutter/fml/memory/ref_counted.h"
+#include "third_party/skia/include/core/SkPoint.h"
+#include "third_party/skia/include/core/SkSize.h"
 
 namespace flow {
 
 class EmbeddedViewParams {
  public:
+  SkPoint offsetPixels;
+  SkSize sizePoints;
 };
 
 // This is only used on iOS when running in a non headless mode,

engine/src/flutter/flow/layers/platform_view_layer.cc

@@ -23,6 +23,11 @@ void PlatformViewLayer::Paint(PaintContext& context) const {
     return;
   }
   EmbeddedViewParams params;
+  SkMatrix transform = context.canvas.getTotalMatrix();
+  params.offsetPixels =
+      SkPoint::Make(transform.getTranslateX(), transform.getTranslateY());
+  params.sizePoints = size_;
+
   context.view_embedder->CompositeEmbeddedView(view_id_, params);
 }
 }  // namespace flow

engine/src/flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformViews.mm

@@ -13,7 +13,9 @@
 namespace shell {
 
 FlutterPlatformViewsController::FlutterPlatformViewsController(
-    NSObject<FlutterBinaryMessenger>* messenger) {
+    NSObject<FlutterBinaryMessenger>* messenger,
+    FlutterView* flutter_view)
+    : flutter_view_([flutter_view retain]) {
   channel_.reset([[FlutterMethodChannel alloc]
          initWithName:@"flutter/platform_views"
       binaryMessenger:messenger
@@ -58,6 +60,9 @@ void FlutterPlatformViewsController::OnCreate(FlutterMethodCall* call, FlutterRe
   views_[viewId] = fml::scoped_nsobject<UIView>([[factory createWithFrame:CGRectZero
                                                            viewIdentifier:viewId
                                                                 arguments:nil] retain]);
+
+  FlutterView* flutter_view = flutter_view_.get();
+  [flutter_view addSubview:views_[viewId].get()];
   result(nil);
 }
 
@@ -72,6 +77,8 @@ void FlutterPlatformViewsController::OnDispose(FlutterMethodCall* call, FlutterR
     return;
   }
 
+  UIView* view = views_[viewId].get();
+  [view removeFromSuperview];
   views_.erase(viewId);
   result(nil);
 }
@@ -87,7 +94,16 @@ void FlutterPlatformViewsController::RegisterViewFactory(
 
 void FlutterPlatformViewsController::CompositeEmbeddedView(int view_id,
                                                            const flow::EmbeddedViewParams& params) {
-  // TODO(amirh): implement this.
+  // TODO(amirh): assert that this is running on the platform thread once we support the iOS
+  // embedded views thread configuration.
+  // TODO(amirh): do nothing if the params didn't change.
+  CGFloat screenScale = [[UIScreen mainScreen] scale];
+  CGRect rect =
+      CGRectMake(params.offsetPixels.x() / screenScale, params.offsetPixels.y() / screenScale,
+                 params.sizePoints.width(), params.sizePoints.height());
+
+  UIView* view = views_[view_id];
+  [view setFrame:rect];
 }
 
 }  // namespace shell

engine/src/flutter/shell/platform/darwin/ios/framework/Source/FlutterPlatformViews_Internal.h

@@ -5,6 +5,7 @@
 #ifndef FLUTTER_SHELL_PLATFORM_DARWIN_IOS_FRAMEWORK_SOURCE_FLUTTERPLATFORMVIEWS_INTERNAL_H_
 #define FLUTTER_SHELL_PLATFORM_DARWIN_IOS_FRAMEWORK_SOURCE_FLUTTERPLATFORMVIEWS_INTERNAL_H_
 
+#include "FlutterView.h"
 #include "flutter/flow/embedded_views.h"
 #include "flutter/fml/platform/darwin/scoped_nsobject.h"
 #include "flutter/shell/common/shell.h"
@@ -16,7 +17,8 @@ namespace shell {
 
 class FlutterPlatformViewsController : public flow::ExternalViewEmbedder {
  public:
-  FlutterPlatformViewsController(NSObject<FlutterBinaryMessenger>* messenger);
+  FlutterPlatformViewsController(NSObject<FlutterBinaryMessenger>* messenger,
+                                 FlutterView* flutter_view);
 
   void RegisterViewFactory(NSObject<FlutterPlatformViewFactory>* factory, NSString* factoryId);
 
@@ -24,6 +26,7 @@ class FlutterPlatformViewsController : public flow::ExternalViewEmbedder {
 
  private:
   fml::scoped_nsobject<FlutterMethodChannel> channel_;
+  fml::scoped_nsobject<FlutterView> flutter_view_;
   std::map<std::string, fml::scoped_nsobject<NSObject<FlutterPlatformViewFactory>>> factories_;
   std::map<int64_t, fml::scoped_nsobject<UIView>> views_;
 

engine/src/flutter/shell/platform/darwin/ios/framework/Source/FlutterViewController.mm

@@ -113,7 +113,8 @@
   _statusBarStyle = UIStatusBarStyleDefault;
 
   [self setupNotificationCenterObservers];
-  _platformViewsController.reset(new shell::FlutterPlatformViewsController(_engine.get()));
+  _platformViewsController.reset(
+      new shell::FlutterPlatformViewsController(_engine.get(), _flutterView.get()));
 }
 
 - (fml::scoped_nsobject<FlutterEngine>)engine {