flutter · auto-submit · Oct 27, 2023 · Oct 26, 2023
diff --git a/shell/common/shell.cc b/shell/common/shell.cc
@@ -814,7 +814,6 @@ void Shell::OnPlatformViewCreated(std::unique_ptr<Surface> surface) {
   const bool should_post_raster_task =
       !task_runners_.GetRasterTaskRunner()->RunsTasksOnCurrentThread();
 
-  fml::AutoResetWaitableEvent latch;
   auto raster_task = fml::MakeCopyable(
       [&waiting_for_first_frame = waiting_for_first_frame_,  //
        rasterizer = rasterizer_->GetWeakPtr(),               //
@@ -841,8 +840,8 @@ void Shell::OnPlatformViewCreated(std::unique_ptr<Surface> surface) {
   // weak pointer. However, we are preventing the platform view from being
   // collected by using a latch.
   auto* platform_view = platform_view_.get();
-
   FML_DCHECK(platform_view);
+  fml::AutoResetWaitableEvent latch;
 
   auto io_task = [io_manager = io_manager_->GetWeakPtr(), platform_view,
                   ui_task_runner = task_runners_.GetUITaskRunner(), ui_task,

diff --git a/shell/platform/android/io/flutter/embedding/android/FlutterImageView.java b/shell/platform/android/io/flutter/embedding/android/FlutterImageView.java
@@ -186,6 +186,10 @@ public void pause() {
     // Not supported.
   }
 
+  public void resume() {
+    // Not supported.
+  }
+
   /**
    * Acquires the next image to be drawn to the {@link android.graphics.Canvas}. Returns true if
    * there's an image available in the queue.

diff --git a/shell/platform/android/io/flutter/embedding/android/FlutterSurfaceView.java b/shell/platform/android/io/flutter/embedding/android/FlutterSurfaceView.java
@@ -38,9 +38,12 @@ public class FlutterSurfaceView extends SurfaceView implements RenderSurface {
   private final boolean renderTransparently;
   private boolean isSurfaceAvailableForRendering = false;
   private boolean isPaused = false;
-  private boolean isAttachedToFlutterRenderer = false;
   @Nullable private FlutterRenderer flutterRenderer;
 
+  private boolean shouldNotify() {
+    return flutterRenderer != null && !isPaused;
+  }
+
   // Connects the {@code Surface} beneath this {@code SurfaceView} with Flutter's native code.
   // Callbacks are received by this Object and then those messages are forwarded to our
   // FlutterRenderer, and then on to the JNI bridge over to native Flutter code.
@@ -51,7 +54,7 @@ public void surfaceCreated(@NonNull SurfaceHolder holder) {
           Log.v(TAG, "SurfaceHolder.Callback.startRenderingToSurface()");
           isSurfaceAvailableForRendering = true;
 
-          if (isAttachedToFlutterRenderer) {
+          if (shouldNotify()) {
             connectSurfaceToRenderer();
           }
         }
@@ -60,7 +63,7 @@ public void surfaceCreated(@NonNull SurfaceHolder holder) {
         public void surfaceChanged(
             @NonNull SurfaceHolder holder, int format, int width, int height) {
           Log.v(TAG, "SurfaceHolder.Callback.surfaceChanged()");
-          if (isAttachedToFlutterRenderer) {
+          if (shouldNotify()) {
             changeSurfaceSize(width, height);
           }
         }
@@ -70,7 +73,7 @@ public void surfaceDestroyed(@NonNull SurfaceHolder holder) {
           Log.v(TAG, "SurfaceHolder.Callback.stopRenderingToSurface()");
           isSurfaceAvailableForRendering = false;
 
-          if (isAttachedToFlutterRenderer) {
+          if (shouldNotify()) {
             disconnectSurfaceFromRenderer();
           }
         }
@@ -183,25 +186,15 @@ public void attachToRenderer(@NonNull FlutterRenderer flutterRenderer) {
     if (this.flutterRenderer != null) {
       Log.v(
           TAG,
-          "Already connected to a FlutterRenderer. Detaching from old one and attaching to new one.");
+          "Already connected to a FlutterRenderer. Detaching from old one and attaching to new"
+              + " one.");
       this.flutterRenderer.stopRenderingToSurface();
       this.flutterRenderer.removeIsDisplayingFlutterUiListener(flutterUiDisplayListener);
     }
 
     this.flutterRenderer = flutterRenderer;
-    isAttachedToFlutterRenderer = true;
 
-    this.flutterRenderer.addIsDisplayingFlutterUiListener(flutterUiDisplayListener);
-
-    // If we're already attached to an Android window then we're now attached to both a renderer
-    // and the Android window. We can begin rendering now.
-    if (isSurfaceAvailableForRendering) {
-      Log.v(
-          TAG,
-          "Surface is available for rendering. Connecting FlutterRenderer to Android surface.");
-      connectSurfaceToRenderer();
-    }
-    isPaused = false;
+    resume();
   }
 
   /**
@@ -222,13 +215,13 @@ public void detachFromRenderer() {
         disconnectSurfaceFromRenderer();
       }
 
+      pause();
+
       // Make the SurfaceView invisible to avoid showing a black rectangle.
       setAlpha(0.0f);
-
       flutterRenderer.removeIsDisplayingFlutterUiListener(flutterUiDisplayListener);
-
       flutterRenderer = null;
-      isAttachedToFlutterRenderer = false;
+
     } else {
       Log.w(TAG, "detachFromRenderer() invoked when no FlutterRenderer was attached.");
     }
@@ -239,22 +232,37 @@ public void detachFromRenderer() {
    * UI to this {@code FlutterSurfaceView}.
    */
   public void pause() {
-    if (flutterRenderer != null) {
-      // Don't remove the `flutterUiDisplayListener` as `onFlutterUiDisplayed()` will make
-      // the `FlutterSurfaceView` visible.
-      flutterRenderer = null;
-      isPaused = true;
-      isAttachedToFlutterRenderer = false;
-    } else {
+    if (flutterRenderer == null) {
       Log.w(TAG, "pause() invoked when no FlutterRenderer was attached.");
+      return;
+    }
+    isPaused = true;
+  }
+
+  public void resume() {
+    if (flutterRenderer == null) {
+      Log.w(TAG, "resume() invoked when no FlutterRenderer was attached.");
+      return;
+    }
+    this.flutterRenderer.addIsDisplayingFlutterUiListener(flutterUiDisplayListener);
+
+    // If we're already attached to an Android window then we're now attached to both a renderer
+    // and the Android window. We can begin rendering now.
+    if (isSurfaceAvailableForRendering) {
+      Log.v(
+          TAG,
+          "Surface is available for rendering. Connecting FlutterRenderer to Android surface.");
+      connectSurfaceToRenderer();
     }
+    isPaused = false;
   }
 
   // FlutterRenderer and getSurfaceTexture() must both be non-null.
   private void connectSurfaceToRenderer() {
     if (flutterRenderer == null || getHolder() == null) {
       throw new IllegalStateException(
-          "connectSurfaceToRenderer() should only be called when flutterRenderer and getHolder() are non-null.");
+          "connectSurfaceToRenderer() should only be called when flutterRenderer and getHolder()"
+              + " are non-null.");
     }
     // When connecting the surface to the renderer, it's possible that the surface is currently
     // paused. For instance, when a platform view is displayed, the current FlutterSurfaceView
@@ -285,9 +293,10 @@ private void changeSurfaceSize(int width, int height) {
   private void disconnectSurfaceFromRenderer() {
     if (flutterRenderer == null) {
       throw new IllegalStateException(
-          "disconnectSurfaceFromRenderer() should only be called when flutterRenderer is non-null.");
+          "disconnectSurfaceFromRenderer() should only be called when flutterRenderer is"
+              + " non-null.");
     }
 
     flutterRenderer.stopRenderingToSurface();
   }
-}
+}
diff --git a/shell/platform/android/io/flutter/embedding/android/FlutterTextureView.java b/shell/platform/android/io/flutter/embedding/android/FlutterTextureView.java
@@ -35,11 +35,14 @@ public class FlutterTextureView extends TextureView implements RenderSurface {
   private static final String TAG = "FlutterTextureView";
 
   private boolean isSurfaceAvailableForRendering = false;
-  private boolean isAttachedToFlutterRenderer = false;
   private boolean isPaused = false;
   @Nullable private FlutterRenderer flutterRenderer;
   @Nullable private Surface renderSurface;
 
+  private boolean shouldNotify() {
+    return flutterRenderer != null && !isPaused;
+  }
+
   // Connects the {@code SurfaceTexture} beneath this {@code TextureView} with Flutter's native
   // code.
   // Callbacks are received by this Object and then those messages are forwarded to our
@@ -55,7 +58,7 @@ public void onSurfaceTextureAvailable(
           // If we're already attached to a FlutterRenderer then we're now attached to both a
           // renderer
           // and the Android window, so we can begin rendering now.
-          if (isAttachedToFlutterRenderer) {
+          if (shouldNotify()) {
             connectSurfaceToRenderer();
           }
         }
@@ -64,7 +67,7 @@ public void onSurfaceTextureAvailable(
         public void onSurfaceTextureSizeChanged(
             @NonNull SurfaceTexture surface, int width, int height) {
           Log.v(TAG, "SurfaceTextureListener.onSurfaceTextureSizeChanged()");
-          if (isAttachedToFlutterRenderer) {
+          if (shouldNotify()) {
             changeSurfaceSize(width, height);
           }
         }
@@ -82,7 +85,7 @@ public boolean onSurfaceTextureDestroyed(@NonNull SurfaceTexture surface) {
           // If we're attached to a FlutterRenderer then we need to notify it that our
           // SurfaceTexture
           // has been destroyed.
-          if (isAttachedToFlutterRenderer) {
+          if (shouldNotify()) {
             disconnectSurfaceFromRenderer();
           }
 
@@ -139,21 +142,14 @@ public void attachToRenderer(@NonNull FlutterRenderer flutterRenderer) {
     if (this.flutterRenderer != null) {
       Log.v(
           TAG,
-          "Already connected to a FlutterRenderer. Detaching from old one and attaching to new one.");
+          "Already connected to a FlutterRenderer. Detaching from old one and attaching to new"
+              + " one.");
       this.flutterRenderer.stopRenderingToSurface();
     }
 
     this.flutterRenderer = flutterRenderer;
-    isAttachedToFlutterRenderer = true;
 
-    // If we're already attached to an Android window then we're now attached to both a renderer
-    // and the Android window. We can begin rendering now.
-    if (isSurfaceAvailableForRendering) {
-      Log.v(
-          TAG,
-          "Surface is available for rendering. Connecting FlutterRenderer to Android surface.");
-      connectSurfaceToRenderer();
-    }
+    resume();
   }
 
   /**
@@ -174,8 +170,9 @@ public void detachFromRenderer() {
         disconnectSurfaceFromRenderer();
       }
 
+      pause();
+
       flutterRenderer = null;
-      isAttachedToFlutterRenderer = false;
     } else {
       Log.w(TAG, "detachFromRenderer() invoked when no FlutterRenderer was attached.");
     }
@@ -186,13 +183,28 @@ public void detachFromRenderer() {
    * UI to this {@code FlutterTextureView}.
    */
   public void pause() {
-    if (flutterRenderer != null) {
-      flutterRenderer = null;
-      isPaused = true;
-      isAttachedToFlutterRenderer = false;
-    } else {
+    if (flutterRenderer == null) {
       Log.w(TAG, "pause() invoked when no FlutterRenderer was attached.");
+      return;
     }
+    isPaused = true;
+  }
+
+  public void resume() {
+    if (flutterRenderer == null) {
+      Log.w(TAG, "resume() invoked when no FlutterRenderer was attached.");
+      return;
+    }
+
+    // If we're already attached to an Android window then we're now attached to both a renderer
+    // and the Android window. We can begin rendering now.
+    if (isSurfaceAvailableForRendering) {
+      Log.v(
+          TAG,
+          "Surface is available for rendering. Connecting FlutterRenderer to Android surface.");
+      connectSurfaceToRenderer();
+    }
+    isPaused = false;
   }
 
   /**
@@ -209,7 +221,8 @@ public void setRenderSurface(Surface renderSurface) {
   private void connectSurfaceToRenderer() {
     if (flutterRenderer == null || getSurfaceTexture() == null) {
       throw new IllegalStateException(
-          "connectSurfaceToRenderer() should only be called when flutterRenderer and getSurfaceTexture() are non-null.");
+          "connectSurfaceToRenderer() should only be called when flutterRenderer and"
+              + " getSurfaceTexture() are non-null.");
     }
 
     // Definitively release the surface to avoid leaked closeables, just in case
@@ -220,7 +233,6 @@ private void connectSurfaceToRenderer() {
 
     renderSurface = new Surface(getSurfaceTexture());
     flutterRenderer.startRenderingToSurface(renderSurface, isPaused);
-    isPaused = false;
   }
 
   // FlutterRenderer must be non-null.
@@ -243,7 +255,8 @@ private void changeSurfaceSize(int width, int height) {
   private void disconnectSurfaceFromRenderer() {
     if (flutterRenderer == null) {
       throw new IllegalStateException(
-          "disconnectSurfaceFromRenderer() should only be called when flutterRenderer is non-null.");
+          "disconnectSurfaceFromRenderer() should only be called when flutterRenderer is"
+              + " non-null.");
     }
 
     flutterRenderer.stopRenderingToSurface();
@@ -252,4 +265,4 @@ private void disconnectSurfaceFromRenderer() {
       renderSurface = null;
     }
   }
-}
+}
diff --git a/shell/platform/android/io/flutter/embedding/android/FlutterView.java b/shell/platform/android/io/flutter/embedding/android/FlutterView.java
@@ -1369,9 +1369,9 @@ public void revertImageView(@NonNull Runnable onDone) {
       onDone.run();
       return;
     }
-    // Start rendering on the previous surface.
+    // Resume rendering to the previous surface.
     // This surface is typically `FlutterSurfaceView` or `FlutterTextureView`.
-    renderSurface.attachToRenderer(renderer);
+    renderSurface.resume();
 
     // Install a Flutter UI listener to wait until the first frame is rendered
     // in the new surface to call the `onDone` callback.

diff --git a/shell/platform/android/io/flutter/embedding/engine/renderer/FlutterRenderer.java b/shell/platform/android/io/flutter/embedding/engine/renderer/FlutterRenderer.java
@@ -467,20 +467,26 @@ protected void finalize() throws Throwable {
    * android.view.TextureView.SurfaceTextureListener}
    *
    * @param surface The render surface.
-   * @param keepCurrentSurface True if the current active surface should not be released.
+   * @param onlySwap True if the current active surface should not be detached.
    */
-  public void startRenderingToSurface(@NonNull Surface surface, boolean keepCurrentSurface) {
-    // Don't stop rendering the surface if it's currently paused.
-    // Stop rendering to the surface releases the associated native resources, which
-    // causes a glitch when showing platform views.
-    // For more, https://github.com/flutter/flutter/issues/95343
-    if (this.surface != null && !keepCurrentSurface) {
+  public void startRenderingToSurface(@NonNull Surface surface, boolean onlySwap) {
+    if (!onlySwap) {
+      // Stop rendering to the surface releases the associated native resources, which
+      // causes a glitch when toggling between rendering to an image view (hybrid composition) and
+      // rendering directly to a Surface or Texture view. For more,
+      // https://github.com/flutter/flutter/issues/95343
       stopRenderingToSurface();
     }
 
     this.surface = surface;
 
-    flutterJNI.onSurfaceCreated(surface);
+    if (onlySwap) {
+      // In the swap case we are just swapping the surface that we render to.
+      flutterJNI.onSurfaceWindowChanged(surface);
+    } else {
+      // In the non-swap case we are creating a new surface to render to.
+      flutterJNI.onSurfaceCreated(surface);
+    }
   }
 
   /**

diff --git a/shell/platform/android/io/flutter/embedding/engine/renderer/RenderSurface.java b/shell/platform/android/io/flutter/embedding/engine/renderer/RenderSurface.java
@@ -60,4 +60,11 @@ public interface RenderSurface {
    * #attachToRenderer(FlutterRenderer)}.
    */
   void pause();
+
+  /**
+   * Instructs this {@code RenderSurface} to resume forwarding {@code Surface} notifications to the
+   * {@code FlutterRenderer} that was previously connected with {@link
+   * #attachToRenderer(FlutterRenderer)}.
+   */
+  void resume();
 }
diff --git a/shell/platform/android/platform_view_android.cc b/shell/platform/android/platform_view_android.cc
@@ -197,6 +197,8 @@ void PlatformViewAndroid::NotifySurfaceWindowChanged(
         });
     latch.Wait();
   }
+
+  PlatformView::ScheduleFrame();
 }
 
 void PlatformViewAndroid::NotifyDestroyed() {
-Original file line number
+Diff line change
@@ Expand Up / @@ -197,6 +197,8 @@ void PlatformViewAndroid::NotifySurfaceWindowChanged( @@
             });
         latch.Wait();
       }
+      PlatformView::ScheduleFrame();
     }
     void PlatformViewAndroid::NotifyDestroyed() {
@@ Expand Down @@