[Android] Fix initial route when app launched by deeplink and not in background

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

@@ -85,21 +85,33 @@ public interface DelegateFactory {
   @VisibleForTesting @Nullable FlutterView flutterView;
   @Nullable private PlatformPlugin platformPlugin;
   @VisibleForTesting @Nullable OnPreDrawListener activePreDrawListener;
+  @VisibleForTesting boolean hasPushedRouteInformation = false;
   private boolean isFlutterEngineFromHost;
   private boolean isFlutterUiDisplayed;
   private boolean isFirstFrameRendered;
   private boolean isAttached;
   private Integer previousVisibility;
   @Nullable private FlutterEngineGroup engineGroup;
 
-  @NonNull
-  private final FlutterUiDisplayListener flutterUiDisplayListener =
+  @NonNull @VisibleForTesting
+  final FlutterUiDisplayListener flutterUiDisplayListener =
       new FlutterUiDisplayListener() {
         @Override
         public void onFlutterUiDisplayed() {
           host.onFlutterUiDisplayed();
           isFlutterUiDisplayed = true;
           isFirstFrameRendered = true;
+
+          // Push updated route information if not pushed by onNewIntent(Intent)
+          // after the first frame has been drawn to ensure it is not ignored.
+          if (flutterEngine != null && !hasPushedRouteInformation) {
+            ensureAlive();
+            String initialRoute = maybeGetInitialRouteFromIntent(host.getActivity().getIntent());
+            if (initialRoute != null && !initialRoute.isEmpty()) {
+              flutterEngine.getNavigationChannel().pushRouteInformation(initialRoute);
+              hasPushedRouteInformation = true;
+            }
+          }
         }
 
         @Override
@@ -836,6 +848,7 @@ void onNewIntent(@NonNull Intent intent) {
       String initialRoute = maybeGetInitialRouteFromIntent(intent);
       if (initialRoute != null && !initialRoute.isEmpty()) {
         flutterEngine.getNavigationChannel().pushRouteInformation(initialRoute);
+        hasPushedRouteInformation = true;
       }
     } else {
       Log.w(TAG, "onNewIntent() invoked before FlutterFragment was attached to an Activity.");

shell/platform/android/test/io/flutter/embedding/android/FlutterActivityAndFragmentDelegateTest.java

@@ -5,12 +5,14 @@
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertThrows;
+import static org.junit.Assert.assertTrue;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.ArgumentMatchers.isNotNull;
 import static org.mockito.ArgumentMatchers.isNull;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.reset;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
@@ -1189,6 +1191,36 @@ public void usesFlutterEngineGroup() {
     assertEquals(engineUnderTest, mockFlutterEngine);
   }
 
+  @Test
+  public void pushesRouteInformationAfterFirstFrameIfApplicable() {
+    FlutterActivityAndFragmentDelegate delegate = new FlutterActivityAndFragmentDelegate(mockHost);
+    Activity mockActivity = mock(Activity.class);
+    Intent mockIntent = mock(Intent.class);
+
+    delegate.onAttach(ctx);
+    FlutterUiDisplayListener flutterUiDisplayListener = delegate.flutterUiDisplayListener;
+    when(mockHost.shouldHandleDeeplinking()).thenReturn(true);
+    when(mockHost.getActivity()).thenReturn(mockActivity);
+    when(mockActivity.getIntent()).thenReturn(mockIntent);
+    when(mockIntent.getData()).thenReturn(Uri.parse("http://myApp/custom/route?query=test"));
+
+    // Test case where updated route information has not already been pushed.
+    flutterUiDisplayListener.onFlutterUiDisplayed();
+
+    verify(mockFlutterEngine.getNavigationChannel(), times(1))
+        .pushRouteInformation("/custom/route?query=test");
+    assertTrue(delegate.hasPushedRouteInformation);
+
+    // Test case where updated route information has already been pushed.
+    reset(mockFlutterEngine.getNavigationChannel());
+    delegate.hasPushedRouteInformation = true;
+
+    flutterUiDisplayListener.onFlutterUiDisplayed();
+
+    verify(mockFlutterEngine.getNavigationChannel(), times(0))
+        .pushRouteInformation(any(String.class));
+  }
+
   /**
    * Creates a mock {@link io.flutter.embedding.engine.FlutterEngine}.
    *