[webview_flutter] Add file upload on Android

packages/webview_flutter/webview_flutter/lib/src/webview.dart

@@ -63,6 +63,8 @@ typedef PageFinishedCallback = void Function(String url);
 /// Signature for when a [WebView] is loading a page.
 typedef PageLoadingCallback = void Function(int progress);
 
+typedef ShowFileChooserCallBack = Future<List<String>> Function();
+
 /// Signature for when a [WebView] has failed to load a resource.
 typedef WebResourceErrorCallback = void Function(WebResourceError error);
 
@@ -90,6 +92,7 @@ class WebView extends StatefulWidget {
     this.onPageStarted,
     this.onPageFinished,
     this.onProgress,
+    this.onShowFileChooser,
     this.onWebResourceError,
     this.debuggingEnabled = false,
     this.gestureNavigationEnabled = false,
@@ -238,6 +241,9 @@ class WebView extends StatefulWidget {
   /// Invoked when a page is loading.
   final PageLoadingCallback? onProgress;
 
+  /// Invoked when a page is loading.
+  final ShowFileChooserCallBack? onShowFileChooser;
+
   /// Invoked when a web resource has failed to load.
   ///
   /// This callback is only called for the main page.
@@ -484,6 +490,14 @@ class _PlatformCallbacksHandler implements WebViewPlatformCallbacksHandler {
     }
   }
 
+  @override
+  Future<List<String>> onShowFileChooser() async {
+    if (_widget.onShowFileChooser != null) {
+      return await _widget.onShowFileChooser!();
+    }
+    return [];
+  }
+
   @override
   void onWebResourceError(WebResourceError error) {
     if (_widget.onWebResourceError != null) {

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

@@ -1,7 +1,3 @@
-// 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.
-
 // Autogenerated from Pigeon (v1.0.9), do not edit directly.
 // See also: https://pub.dev/packages/pigeon
 
@@ -2197,6 +2193,22 @@ public void onProgressChanged(
             callback.reply(null);
           });
     }
+
+    public void onShowFileChooser(
+        Long instanceIdArg, Long webViewInstanceIdArg, Reply<List<String>> callback) {
+      BasicMessageChannel<Object> channel =
+          new BasicMessageChannel<>(
+              binaryMessenger,
+              "dev.flutter.pigeon.WebChromeClientFlutterApi.onShowFileChooser",
+              getCodec());
+      channel.send(
+          new ArrayList<Object>(Arrays.asList(instanceIdArg, webViewInstanceIdArg)),
+          channelReply -> {
+            @SuppressWarnings("ConstantConditions")
+            List<String> output = (List<String>) channelReply;
+            callback.reply(output);
+          });
+    }
   }
 
   private static class WebStorageHostApiCodec extends StandardMessageCodec {

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

@@ -8,6 +8,7 @@
 import android.webkit.WebView;
 import io.flutter.plugin.common.BinaryMessenger;
 import io.flutter.plugins.webviewflutter.GeneratedAndroidWebView.WebChromeClientFlutterApi;
+import java.util.List;
 
 /**
  * Flutter Api implementation for {@link WebChromeClient}.
@@ -39,6 +40,15 @@ public void onProgressChanged(
         callback);
   }
 
+  /** Passes arguments from {@link WebChromeClient#onProgressChanged} to Dart. */
+  public void onShowFileChooser(
+      WebChromeClient webChromeClient, WebView webView, Reply<List<String>> callback) {
+    super.onShowFileChooser(
+        instanceManager.getInstanceId(webChromeClient),
+        instanceManager.getInstanceId(webView),
+        callback);
+  }
+
   /**
    * Communicates to Dart that the reference to a {@link WebChromeClient}} was removed.
    *

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

@@ -4,8 +4,10 @@
 
 package io.flutter.plugins.webviewflutter;
 
+import android.net.Uri;
 import android.os.Build;
 import android.os.Message;
+import android.webkit.ValueCallback;
 import android.webkit.WebChromeClient;
 import android.webkit.WebResourceRequest;
 import android.webkit.WebView;
@@ -14,7 +16,10 @@
 import androidx.annotation.Nullable;
 import androidx.annotation.RequiresApi;
 import androidx.annotation.VisibleForTesting;
+import io.flutter.plugins.webviewflutter.GeneratedAndroidWebView.WebChromeClientFlutterApi;
 import io.flutter.plugins.webviewflutter.GeneratedAndroidWebView.WebChromeClientHostApi;
+import java.io.File;
+import java.util.List;
 
 /**
  * Host api implementation for {@link WebChromeClient}.
@@ -100,6 +105,30 @@ public boolean shouldOverrideUrlLoading(WebView windowWebView, String url) {
       return true;
     }
 
+    @Override
+    public boolean onShowFileChooser(
+        WebView view,
+        ValueCallback<Uri[]> filePathCallback,
+        WebChromeClient.FileChooserParams fileChooserParams) {
+      if (flutterApi != null) {
+        flutterApi.onShowFileChooser(
+            this,
+            view,
+            new WebChromeClientFlutterApi.Reply<List<String>>() {
+              public void reply(List<String> paths) {
+                final Uri[] uris = new Uri[paths.size()];
+                for (int i = 0; i < uris.length; i++) {
+                  uris[i] = Uri.fromFile(new File(paths.get(i)));
+                }
+                filePathCallback.onReceiveValue(uris);
+              }
+            });
+        return true;
+      }
+      filePathCallback.onReceiveValue(null);
+      return true;
+    }
+
     @Override
     public void onProgressChanged(WebView view, int progress) {
       if (flutterApi != null) {

packages/webview_flutter/webview_flutter_android/lib/src/android_webview.dart

@@ -781,6 +781,10 @@ abstract class WebChromeClient {
 
   /// Notify the host application that a file should be downloaded.
   void onProgressChanged(WebView webView, int progress) {}
+
+  Future<List<String>> onShowFileChooser(WebView webView) async {
+    return [];
+  }
 }
 
 /// Encompasses parameters to the [WebViewClient.requestLoading] method.

packages/webview_flutter/webview_flutter_android/lib/src/android_webview.pigeon.dart

@@ -1,7 +1,3 @@
-// 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.
-
 // Autogenerated from Pigeon (v1.0.9), do not edit directly.
 // See also: https://pub.dev/packages/pigeon
 // ignore_for_file: public_member_api_docs, non_constant_identifier_names, avoid_as, unused_import, unnecessary_parenthesis, prefer_null_aware_operators, omit_local_variable_types, unused_shown_name
@@ -1810,6 +1806,8 @@ abstract class WebChromeClientFlutterApi {
 
   void dispose(int instanceId);
   void onProgressChanged(int instanceId, int webViewInstanceId, int progress);
+  Future<List<String?>> onShowFileChooser(
+      int instanceId, int webViewInstanceId);
   static void setup(WebChromeClientFlutterApi? api,
       {BinaryMessenger? binaryMessenger}) {
     {
@@ -1858,6 +1856,30 @@ abstract class WebChromeClientFlutterApi {
         });
       }
     }
+    {
+      final BasicMessageChannel<Object?> channel = BasicMessageChannel<Object?>(
+          'dev.flutter.pigeon.WebChromeClientFlutterApi.onShowFileChooser',
+          codec,
+          binaryMessenger: binaryMessenger);
+      if (api == null) {
+        channel.setMessageHandler(null);
+      } else {
+        channel.setMessageHandler((Object? message) async {
+          assert(message != null,
+              'Argument for dev.flutter.pigeon.WebChromeClientFlutterApi.onShowFileChooser was null.');
+          final List<Object?> args = (message as List<Object?>?)!;
+          final int? arg_instanceId = (args[0] as int?);
+          assert(arg_instanceId != null,
+              'Argument for dev.flutter.pigeon.WebChromeClientFlutterApi.onShowFileChooser was null, expected non-null int.');
+          final int? arg_webViewInstanceId = (args[1] as int?);
+          assert(arg_webViewInstanceId != null,
+              'Argument for dev.flutter.pigeon.WebChromeClientFlutterApi.onShowFileChooser was null, expected non-null int.');
+          final List<String?> output = await api.onShowFileChooser(
+              arg_instanceId!, arg_webViewInstanceId!);
+          return output;
+        });
+      }
+    }
   }
 }
 

packages/webview_flutter/webview_flutter_android/lib/src/android_webview_api_impls.dart

@@ -786,6 +786,25 @@ class WebChromeClientFlutterApiImpl extends WebChromeClientFlutterApi {
     );
     instance!.onProgressChanged(webViewInstance!, progress);
   }
+
+  @override
+  Future<List<String>> onShowFileChooser(
+      int instanceId, int webViewInstanceId) async {
+    final WebChromeClient? instance =
+        instanceManager.getInstance(instanceId) as WebChromeClient?;
+    final WebView? webViewInstance =
+        instanceManager.getInstance(webViewInstanceId) as WebView?;
+    assert(
+      instance != null,
+      'InstanceManager does not contain an WebChromeClient with instanceId: $instanceId',
+    );
+    assert(
+      webViewInstance != null,
+      'InstanceManager does not contain an WebView with instanceId: $webViewInstanceId',
+    );
+    // AFAIRE
+    return await instance!.onShowFileChooser(webViewInstance!);
+  }
 }
 
 /// Host api implementation for [WebStorage].

packages/webview_flutter/webview_flutter_android/lib/webview_android_widget.dart

@@ -389,6 +389,7 @@ class WebViewAndroidPlatformController extends WebViewPlatformController {
   }
 
   Future<void> _setHasProgressTracking(bool hasProgressTracking) async {
+    webChromeClient._onShowFileChooser = callbacksHandler.onShowFileChooser;
     if (hasProgressTracking) {
       webChromeClient._onProgress = callbacksHandler.onProgress;
     } else {
@@ -690,13 +691,23 @@ class WebViewAndroidWebViewClient extends android_webview.WebViewClient {
 class WebViewAndroidWebChromeClient extends android_webview.WebChromeClient {
   // Changed by WebViewAndroidPlatformController.
   void Function(int progress)? _onProgress;
+  Future<List<String>> Function()? _onShowFileChooser;
 
   @override
   void onProgressChanged(android_webview.WebView webView, int progress) {
     if (_onProgress != null) {
       _onProgress!(progress);
     }
   }
+
+  @override
+  Future<List<String>> onShowFileChooser(
+      android_webview.WebView webView) async {
+    if (_onShowFileChooser != null) {
+      return await _onShowFileChooser!();
+    }
+    return [];
+  }
 }
 
 /// Handles constructing [android_webview.WebView]s and calling static methods.

packages/webview_flutter/webview_flutter_android/pigeons/android_webview.dart

@@ -221,6 +221,9 @@ abstract class WebChromeClientFlutterApi {
   void dispose(int instanceId);
 
   void onProgressChanged(int instanceId, int webViewInstanceId, int progress);
+
+  @async
+  List<String> onShowFileChooser(int instanceId, int webViewInstanceId);
 }
 
 @HostApi(dartHostTestHandler: 'TestWebStorageHostApi')

packages/webview_flutter/webview_flutter_android/test/android_webview.pigeon.dart

@@ -1,7 +1,3 @@
-// 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.
-
 // Autogenerated from Pigeon (v1.0.9), do not edit directly.
 // See also: https://pub.dev/packages/pigeon
 // ignore_for_file: public_member_api_docs, non_constant_identifier_names, avoid_as, unused_import
@@ -12,7 +8,7 @@ import 'package:flutter/foundation.dart' show WriteBuffer, ReadBuffer;
 import 'package:flutter/services.dart';
 import 'package:flutter_test/flutter_test.dart';
 
-import 'package:webview_flutter_android/src/android_webview.pigeon.dart';
+import '../lib/src/android_webview.pigeon.dart';
 
 class _TestWebViewHostApiCodec extends StandardMessageCodec {
   const _TestWebViewHostApiCodec();

packages/webview_flutter/webview_flutter_platform_interface/lib/src/method_channel/webview_method_channel.dart

@@ -51,6 +51,8 @@ class MethodChannelWebViewPlatform implements WebViewPlatformController {
       case 'onProgress':
         _platformCallbacksHandler.onProgress(call.arguments['progress'] as int);
         return null;
+      //case 'onShowFileChooser':
+      //return await _platformCallbacksHandler.onShowFileChooser();
       case 'onPageStarted':
         _platformCallbacksHandler
             .onPageStarted(call.arguments['url']! as String);

packages/webview_flutter/webview_flutter_platform_interface/lib/src/platform_interface/webview_platform_callbacks_handler.dart

@@ -27,6 +27,8 @@ abstract class WebViewPlatformCallbacksHandler {
   /// /// Only works when [WebSettings.hasProgressTracking] is set to `true`.
   void onProgress(int progress);
 
+  Future<List<String>> onShowFileChooser();
+
   /// Report web resource loading error to the host application.
   void onWebResourceError(WebResourceError error);
 }