Fixes iframe navigation being handled in the main frame when `Navigat…

…ionDelegate.onNavigationRequest` is present.

packages/webview_flutter/webview_flutter_android/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 3.16.1
+
+* Fixes iframe navigation being handled in the main frame when `NavigationDelegate.onNavigationRequest` is present.
+
 ## 3.16.0
 
 * Adds onReceivedHttpError WebViewClient callback to support

packages/webview_flutter/webview_flutter_android/android/src/main/java/io/flutter/plugins/webviewflutter/WebViewClientHostApiImpl.java

@@ -88,7 +88,13 @@ public void onReceivedError(
     public boolean shouldOverrideUrlLoading(
         @NonNull WebView view, @NonNull WebResourceRequest request) {
       flutterApi.requestLoading(this, view, request, reply -> {});
-      return returnValueForShouldOverrideUrlLoading;
+
+      // Since we cannot call loadUrl for a subframe, we currently only allow the delegate to stop
+      // navigations that target the main frame, if the request is not for the main frame
+      // we just return false to allow the navigation.
+      //
+      // For more details see: https://github.com/flutter/flutter/issues/25329#issuecomment-464863209
+      return request.isForMainFrame() && returnValueForShouldOverrideUrlLoading;
     }
 
     // Legacy codepath for < 24; newer versions use the variant above.
@@ -187,7 +193,13 @@ public void onReceivedError(
     public boolean shouldOverrideUrlLoading(
         @NonNull WebView view, @NonNull WebResourceRequest request) {
       flutterApi.requestLoading(this, view, request, reply -> {});
-      return returnValueForShouldOverrideUrlLoading;
+
+      // Since we cannot call loadUrl for a subframe, we currently only allow the delegate to stop
+      // navigations that target the main frame, if the request is not for the main frame
+      // we just return false to allow the navigation.
+      //
+      // For more details see: https://github.com/flutter/flutter/issues/25329#issuecomment-464863209
+      return request.isForMainFrame() && returnValueForShouldOverrideUrlLoading;
     }
 
     // Legacy codepath for < Lollipop; newer versions use the variant above.

packages/webview_flutter/webview_flutter_android/android/src/test/java/io/flutter/plugins/webviewflutter/WebViewClientCompatImplTest.java

@@ -0,0 +1,21 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package io.flutter.plugins.webviewflutter;
+
+import android.webkit.WebViewClient;
+
+public class WebViewClientCompatImplTest extends WebViewClientTest {
+
+  @Override
+  WebViewClient createInstance(WebViewClientFlutterApiImpl flutterApi) {
+    return new WebViewClientHostApiImpl.WebViewClientCompatImpl(flutterApi);
+  }
+
+  @Override
+  void setReturnValueForShouldOverrideUrlLoading(WebViewClient client, boolean value) {
+    ((WebViewClientHostApiImpl.WebViewClientCompatImpl) client)
+        .setReturnValueForShouldOverrideUrlLoading(value);
+  }
+}

packages/webview_flutter/webview_flutter_android/android/src/test/java/io/flutter/plugins/webviewflutter/WebViewClientImplTest.java

@@ -0,0 +1,21 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package io.flutter.plugins.webviewflutter;
+
+import android.webkit.WebViewClient;
+
+public class WebViewClientImplTest extends WebViewClientTest {
+
+  @Override
+  WebViewClient createInstance(WebViewClientFlutterApiImpl flutterApi) {
+    return new WebViewClientHostApiImpl.WebViewClientImpl(flutterApi);
+  }
+
+  @Override
+  void setReturnValueForShouldOverrideUrlLoading(WebViewClient client, boolean value) {
+    ((WebViewClientHostApiImpl.WebViewClientImpl) client)
+        .setReturnValueForShouldOverrideUrlLoading(value);
+  }
+}

packages/webview_flutter/webview_flutter_android/android/src/test/java/io/flutter/plugins/webviewflutter/WebViewClientTest.java

@@ -5,6 +5,8 @@
 package io.flutter.plugins.webviewflutter;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.mock;
@@ -28,7 +30,7 @@
 import org.mockito.junit.MockitoJUnit;
 import org.mockito.junit.MockitoRule;
 
-public class WebViewClientTest {
+public abstract class WebViewClientTest {
   @Rule public MockitoRule mockitoRule = MockitoJUnit.rule();
 
   @Mock public WebViewClientFlutterApiImpl mockFlutterApi;
@@ -39,7 +41,11 @@ public class WebViewClientTest {
 
   InstanceManager instanceManager;
   WebViewClientHostApiImpl hostApiImpl;
-  WebViewClientCompatImpl webViewClient;
+  WebViewClient webViewClient;
+
+  abstract WebViewClient createInstance(WebViewClientFlutterApiImpl flutterApi);
+
+  abstract void setReturnValueForShouldOverrideUrlLoading(WebViewClient client, boolean value);
 
   @Before
   public void setUp() {
@@ -51,7 +57,7 @@ public void setUp() {
           @NonNull
           public WebViewClient createWebViewClient(
               @NonNull WebViewClientFlutterApiImpl flutterApi) {
-            webViewClient = (WebViewClientCompatImpl) super.createWebViewClient(flutterApi);
+            webViewClient = createInstance(flutterApi);
             return webViewClient;
           }
         };
@@ -74,6 +80,7 @@ public void onPageStarted() {
   }
 
   @Test
+  @SuppressWarnings("deprecation")
   public void onReceivedError() {
     webViewClient.onReceivedError(mockWebView, 32, "description", "https://www.google.com");
     verify(mockFlutterApi)
@@ -87,12 +94,61 @@ public void onReceivedError() {
   }
 
   @Test
+  @SuppressWarnings("deprecation")
   public void urlLoading() {
     webViewClient.shouldOverrideUrlLoading(mockWebView, "https://www.google.com");
     verify(mockFlutterApi)
         .urlLoading(eq(webViewClient), eq(mockWebView), eq("https://www.google.com"), any());
   }
 
+  @Test
+  public void urlLoadingForMainFrame() {
+    setReturnValueForShouldOverrideUrlLoading(webViewClient, false);
+
+    final WebResourceRequest mockRequest = mock(WebResourceRequest.class);
+    when(mockRequest.isForMainFrame()).thenReturn(true);
+
+    assertFalse(webViewClient.shouldOverrideUrlLoading(mockWebView, mockRequest));
+    verify(mockFlutterApi)
+        .requestLoading(eq(webViewClient), eq(mockWebView), eq(mockRequest), any());
+  }
+
+  @Test
+  public void urlLoadingForMainFrameWithOverride() {
+    setReturnValueForShouldOverrideUrlLoading(webViewClient, true);
+
+    final WebResourceRequest mockRequest = mock(WebResourceRequest.class);
+    when(mockRequest.isForMainFrame()).thenReturn(true);
+
+    assertTrue(webViewClient.shouldOverrideUrlLoading(mockWebView, mockRequest));
+    verify(mockFlutterApi)
+        .requestLoading(eq(webViewClient), eq(mockWebView), eq(mockRequest), any());
+  }
+
+  @Test
+  public void urlLoadingNotForMainFrame() {
+    setReturnValueForShouldOverrideUrlLoading(webViewClient, false);
+
+    final WebResourceRequest mockRequest = mock(WebResourceRequest.class);
+    when(mockRequest.isForMainFrame()).thenReturn(false);
+
+    assertFalse(webViewClient.shouldOverrideUrlLoading(mockWebView, mockRequest));
+    verify(mockFlutterApi)
+        .requestLoading(eq(webViewClient), eq(mockWebView), eq(mockRequest), any());
+  }
+
+  @Test
+  public void urlLoadingNotForMainFrameWithOverride() {
+    setReturnValueForShouldOverrideUrlLoading(webViewClient, true);
+
+    final WebResourceRequest mockRequest = mock(WebResourceRequest.class);
+    when(mockRequest.isForMainFrame()).thenReturn(false);
+
+    assertFalse(webViewClient.shouldOverrideUrlLoading(mockWebView, mockRequest));
+    verify(mockFlutterApi)
+        .requestLoading(eq(webViewClient), eq(mockWebView), eq(mockRequest), any());
+  }
+
   @Test
   public void convertWebResourceRequestWithNullHeaders() {
     final Uri mockUri = mock(Uri.class);

packages/webview_flutter/webview_flutter_android/example/lib/main.dart

@@ -23,10 +23,10 @@ const String kNavigationExamplePage = '''
 <head><title>Navigation Delegate Example</title></head>
 <body>
 <p>
-The navigation delegate is set to block navigation to the youtube website.
+The navigation delegate is set to block navigation to the pub.dev website.
 </p>
 <ul>
-<ul><a href="https://www.youtube.com/">https://www.youtube.com/</a></ul>
+<ul><a href="https://pub.dev/">https://pub.dev/</a></ul>
 <ul><a href="https://www.google.com/">https://www.google.com/</a></ul>
 </ul>
 </body>

packages/webview_flutter/webview_flutter_android/pubspec.yaml

@@ -2,7 +2,7 @@ name: webview_flutter_android
 description: A Flutter plugin that provides a WebView widget on Android.
 repository: https://github.com/flutter/packages/tree/main/packages/webview_flutter/webview_flutter_android
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+webview%22
-version: 3.16.0
+version: 3.16.1
 
 environment:
   sdk: ^3.1.0