Revert "Use preDraw for the Android embedding (#27645)" (#27788)

This reverts commit ff770aa.

Author: jiahaog

shell/platform/android/io/flutter/embedding/android/FlutterActivity.java

@@ -542,8 +542,7 @@ private View createFlutterView() {
         /* inflater=*/ null,
         /* container=*/ null,
         /* savedInstanceState=*/ null,
-        /*flutterViewId=*/ FLUTTER_VIEW_ID,
-        /*shouldDelayFirstAndroidViewDraw=*/ getRenderMode() == RenderMode.surface);
+        /*flutterViewId=*/ FLUTTER_VIEW_ID);
   }
 
   private void configureStatusBarForFullscreenFlutterExperience() {

shell/platform/android/io/flutter/embedding/android/FlutterActivityAndFragmentDelegate.java

@@ -15,7 +15,6 @@
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
-import android.view.ViewTreeObserver.OnPreDrawListener;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.annotation.VisibleForTesting;
@@ -68,31 +67,27 @@
   private static final String TAG = "FlutterActivityAndFragmentDelegate";
   private static final String FRAMEWORK_RESTORATION_BUNDLE_KEY = "framework";
   private static final String PLUGINS_RESTORATION_BUNDLE_KEY = "plugins";
-  private static final int FLUTTER_SPLASH_VIEW_FALLBACK_ID = 486947586;
 
   // The FlutterActivity or FlutterFragment that is delegating most of its calls
   // to this FlutterActivityAndFragmentDelegate.
   @NonNull private Host host;
   @Nullable private FlutterEngine flutterEngine;
+  @Nullable private FlutterSplashView flutterSplashView;
   @Nullable private FlutterView flutterView;
   @Nullable private PlatformPlugin platformPlugin;
-  @VisibleForTesting @Nullable OnPreDrawListener activePreDrawListener;
   private boolean isFlutterEngineFromHost;
-  private boolean isFlutterUiDisplayed;
 
   @NonNull
   private final FlutterUiDisplayListener flutterUiDisplayListener =
       new FlutterUiDisplayListener() {
         @Override
         public void onFlutterUiDisplayed() {
           host.onFlutterUiDisplayed();
-          isFlutterUiDisplayed = true;
         }
 
         @Override
         public void onFlutterUiNoLongerDisplayed() {
           host.onFlutterUiNoLongerDisplayed();
-          isFlutterUiDisplayed = false;
         }
       };
 
@@ -259,16 +254,6 @@ void onAttach(@NonNull Context context) {
    *
    * <p>{@code inflater} and {@code container} may be null when invoked from an {@code Activity}.
    *
-   * <p>{@code shouldDelayFirstAndroidViewDraw} determines whether to set up an {@link
-   * android.view.ViewTreeObserver.OnPreDrawListener}, which will defer the current drawing pass
-   * till after the Flutter UI has been displayed. This results in more accurate timings reported
-   * with Android tools, such as "Displayed" timing printed with `am start`.
-   *
-   * <p>Note that it should only be set to true when {@code Host#getRenderMode()} is {@code
-   * RenderMode.surface}. This parameter is also ignored, disabling the delay should the legacy
-   * {@code Host#provideSplashScreen()} be non-null. See <a
-   * href="https://flutter.dev/go/android-splash-migration">Android Splash Migration</a>.
-   *
    * <p>This method:
    *
    * <ol>
@@ -284,8 +269,7 @@ View onCreateView(
       LayoutInflater inflater,
       @Nullable ViewGroup container,
       @Nullable Bundle savedInstanceState,
-      int flutterViewId,
-      boolean shouldDelayFirstAndroidViewDraw) {
+      int flutterViewId) {
     Log.v(TAG, "Creating FlutterView.");
     ensureAlive();
 
@@ -314,28 +298,15 @@ View onCreateView(
     // Add listener to be notified when Flutter renders its first frame.
     flutterView.addOnFirstFrameRenderedListener(flutterUiDisplayListener);
 
+    flutterSplashView = new FlutterSplashView(host.getContext());
+    flutterSplashView.setId(ViewUtils.generateViewId(486947586));
+    flutterSplashView.displayFlutterViewWithSplash(flutterView, host.provideSplashScreen());
+
     Log.v(TAG, "Attaching FlutterEngine to FlutterView.");
     flutterView.attachToFlutterEngine(flutterEngine);
     flutterView.setId(flutterViewId);
 
-    SplashScreen splashScreen = host.provideSplashScreen();
-
-    if (splashScreen != null) {
-      Log.w(
-          TAG,
-          "A splash screen was provided to Flutter, but this is deprecated. See"
-              + " flutter.dev/go/android-splash-migration for migration steps.");
-      FlutterSplashView flutterSplashView = new FlutterSplashView(host.getContext());
-      flutterSplashView.setId(ViewUtils.generateViewId(FLUTTER_SPLASH_VIEW_FALLBACK_ID));
-      flutterSplashView.displayFlutterViewWithSplash(flutterView, splashScreen);
-
-      return flutterSplashView;
-    }
-
-    if (shouldDelayFirstAndroidViewDraw) {
-      delayFirstAndroidViewDraw(flutterView);
-    }
-    return flutterView;
+    return flutterSplashView;
   }
 
   void onRestoreInstanceState(@Nullable Bundle bundle) {
@@ -444,38 +415,6 @@ private String maybeGetInitialRouteFromIntent(Intent intent) {
     return null;
   }
 
-  /**
-   * Delays the first drawing of the {@code flutterView} until the Flutter first has been displayed.
-   */
-  private void delayFirstAndroidViewDraw(FlutterView flutterView) {
-    if (host.getRenderMode() != RenderMode.surface) {
-      // Using a TextureView will cause a deadlock, where the underlying SurfaceTexture is never
-      // available since it will wait for drawing to be completed first. At the same time, the
-      // preDraw listener keeps returning false since the Flutter Engine waits for the
-      // SurfaceTexture to be available.
-      throw new IllegalArgumentException(
-          "Cannot delay the first Android view draw when the render mode is not set to"
-              + " `RenderMode.surface`.");
-    }
-
-    if (activePreDrawListener != null) {
-      flutterView.getViewTreeObserver().removeOnPreDrawListener(activePreDrawListener);
-    }
-
-    activePreDrawListener =
-        new OnPreDrawListener() {
-          @Override
-          public boolean onPreDraw() {
-            if (isFlutterUiDisplayed && activePreDrawListener != null) {
-              flutterView.getViewTreeObserver().removeOnPreDrawListener(this);
-              activePreDrawListener = null;
-            }
-            return isFlutterUiDisplayed;
-          }
-        };
-    flutterView.getViewTreeObserver().addOnPreDrawListener(activePreDrawListener);
-  }
-
   /**
    * Invoke this from {@code Activity#onResume()} or {@code Fragment#onResume()}.
    *
@@ -557,10 +496,6 @@ void onDestroyView() {
     Log.v(TAG, "onDestroyView()");
     ensureAlive();
 
-    if (activePreDrawListener != null) {
-      flutterView.getViewTreeObserver().removeOnPreDrawListener(activePreDrawListener);
-      activePreDrawListener = null;
-    }
     flutterView.detachFromFlutterEngine();
     flutterView.removeOnFirstFrameRenderedListener(flutterUiDisplayListener);
   }

shell/platform/android/io/flutter/embedding/android/FlutterFragment.java

@@ -113,10 +113,6 @@ public class FlutterFragment extends Fragment
   protected static final String ARG_HANDLE_DEEPLINKING = "handle_deeplinking";
   /** Path to Flutter's Dart code. */
   protected static final String ARG_APP_BUNDLE_PATH = "app_bundle_path";
-  /** Whether to delay the Android drawing pass till after the Flutter UI has been displayed. */
-  protected static final String ARG_SHOULD_DELAY_FIRST_ANDROID_VIEW_DRAW =
-      "should_delay_first_android_view_draw";
-
   /** Flutter shell arguments. */
   protected static final String ARG_FLUTTER_INITIALIZATION_ARGS = "initialization_args";
   /**
@@ -233,7 +229,6 @@ public static class NewEngineFragmentBuilder {
     private TransparencyMode transparencyMode = TransparencyMode.transparent;
     private boolean shouldAttachEngineToActivity = true;
     private boolean shouldAutomaticallyHandleOnBackPressed = false;
-    private boolean shouldDelayFirstAndroidViewDraw = false;
 
     /**
      * Constructs a {@code NewEngineFragmentBuilder} that is configured to construct an instance of
@@ -387,18 +382,6 @@ public NewEngineFragmentBuilder shouldAutomaticallyHandleOnBackPressed(
       return this;
     }
 
-    /**
-     * Whether to delay the Android drawing pass till after the Flutter UI has been displayed.
-     *
-     * <p>See {#link FlutterActivityAndFragmentDelegate#onCreateView} for more details.
-     */
-    @NonNull
-    public NewEngineFragmentBuilder shouldDelayFirstAndroidViewDraw(
-        boolean shouldDelayFirstAndroidViewDraw) {
-      this.shouldDelayFirstAndroidViewDraw = shouldDelayFirstAndroidViewDraw;
-      return this;
-    }
-
     /**
      * Creates a {@link Bundle} of arguments that are assigned to the new {@code FlutterFragment}.
      *
@@ -427,7 +410,6 @@ protected Bundle createArgs() {
       args.putBoolean(ARG_DESTROY_ENGINE_WITH_FRAGMENT, true);
       args.putBoolean(
           ARG_SHOULD_AUTOMATICALLY_HANDLE_ON_BACK_PRESSED, shouldAutomaticallyHandleOnBackPressed);
-      args.putBoolean(ARG_SHOULD_DELAY_FIRST_ANDROID_VIEW_DRAW, shouldDelayFirstAndroidViewDraw);
       return args;
     }
 
@@ -514,7 +496,6 @@ public static class CachedEngineFragmentBuilder {
     private TransparencyMode transparencyMode = TransparencyMode.transparent;
     private boolean shouldAttachEngineToActivity = true;
     private boolean shouldAutomaticallyHandleOnBackPressed = false;
-    private boolean shouldDelayFirstAndroidViewDraw = false;
 
     private CachedEngineFragmentBuilder(@NonNull String engineId) {
       this(FlutterFragment.class, engineId);
@@ -640,18 +621,6 @@ public CachedEngineFragmentBuilder shouldAutomaticallyHandleOnBackPressed(
       return this;
     }
 
-    /**
-     * Whether to delay the Android drawing pass till after the Flutter UI has been displayed.
-     *
-     * <p>See {#link FlutterActivityAndFragmentDelegate#onCreateView} for more details.
-     */
-    @NonNull
-    public CachedEngineFragmentBuilder shouldDelayFirstAndroidViewDraw(
-        @NonNull boolean shouldDelayFirstAndroidViewDraw) {
-      this.shouldDelayFirstAndroidViewDraw = shouldDelayFirstAndroidViewDraw;
-      return this;
-    }
-
     /**
      * Creates a {@link Bundle} of arguments that are assigned to the new {@code FlutterFragment}.
      *
@@ -673,7 +642,6 @@ protected Bundle createArgs() {
       args.putBoolean(ARG_SHOULD_ATTACH_ENGINE_TO_ACTIVITY, shouldAttachEngineToActivity);
       args.putBoolean(
           ARG_SHOULD_AUTOMATICALLY_HANDLE_ON_BACK_PRESSED, shouldAutomaticallyHandleOnBackPressed);
-      args.putBoolean(ARG_SHOULD_DELAY_FIRST_ANDROID_VIEW_DRAW, shouldDelayFirstAndroidViewDraw);
       return args;
     }
 
@@ -759,11 +727,7 @@ public void onCreate(@Nullable Bundle savedInstanceState) {
   public View onCreateView(
       LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
     return delegate.onCreateView(
-        inflater,
-        container,
-        savedInstanceState,
-        /*flutterViewId=*/ FLUTTER_VIEW_ID,
-        shouldDelayFirstAndroidViewDraw());
+        inflater, container, savedInstanceState, /*flutterViewId=*/ FLUTTER_VIEW_ID);
   }
 
   @Override
@@ -1303,12 +1267,6 @@ public boolean popSystemNavigator() {
     return false;
   }
 
-  @VisibleForTesting
-  @NonNull
-  boolean shouldDelayFirstAndroidViewDraw() {
-    return getArguments().getBoolean(ARG_SHOULD_DELAY_FIRST_ANDROID_VIEW_DRAW);
-  }
-
   private boolean stillAttachedForEvent(String event) {
     if (delegate == null) {
       Log.w(TAG, "FlutterFragment " + hashCode() + " " + event + " called after release.");

shell/platform/android/io/flutter/embedding/android/FlutterFragmentActivity.java

@@ -424,7 +424,6 @@ protected FlutterFragment createFlutterFragment() {
         backgroundMode == BackgroundMode.opaque
             ? TransparencyMode.opaque
             : TransparencyMode.transparent;
-    final boolean shouldDelayFirstAndroidViewDraw = renderMode == RenderMode.surface;
 
     if (getCachedEngineId() != null) {
       Log.v(
@@ -448,7 +447,6 @@ protected FlutterFragment createFlutterFragment() {
           .handleDeeplinking(shouldHandleDeeplinking())
           .shouldAttachEngineToActivity(shouldAttachEngineToActivity())
           .destroyEngineWithFragment(shouldDestroyEngineWithHost())
-          .shouldDelayFirstAndroidViewDraw(shouldDelayFirstAndroidViewDraw)
           .build();
     } else {
       Log.v(
@@ -478,7 +476,6 @@ protected FlutterFragment createFlutterFragment() {
           .renderMode(renderMode)
           .transparencyMode(transparencyMode)
           .shouldAttachEngineToActivity(shouldAttachEngineToActivity())
-          .shouldDelayFirstAndroidViewDraw(shouldDelayFirstAndroidViewDraw)
           .build();
     }
   }