Add full-screen support (#189)

example/lib/main.dart

@@ -3,10 +3,15 @@ import 'package:flutter/services.dart';
 import 'dart:async';
 
 import 'package:webview_windows/webview_windows.dart';
+import 'package:window_manager/window_manager.dart';
 
 final navigatorKey = GlobalKey<NavigatorState>();
 
-void main() {
+void main() async {
+  // For full-screen example
+  WidgetsFlutterBinding.ensureInitialized();
+  await windowManager.ensureInitialized();
+
   runApp(MyApp());
 }
 
@@ -25,6 +30,7 @@ class ExampleBrowser extends StatefulWidget {
 class _ExampleBrowser extends State<ExampleBrowser> {
   final _controller = WebviewController();
   final _textController = TextEditingController();
+  final List<StreamSubscription> _subscriptions = [];
   bool _isWebviewSuspended = false;
 
   @override
@@ -43,9 +49,15 @@ class _ExampleBrowser extends State<ExampleBrowser> {
 
     try {
       await _controller.initialize();
-      _controller.url.listen((url) {
+      _subscriptions.add(_controller.url.listen((url) {
         _textController.text = url;
-      });
+      }));
+
+      _subscriptions
+          .add(_controller.containsFullScreenElementChanged.listen((flag) {
+        debugPrint('Contains fullscreen element: $flag');
+        windowManager.setFullScreen(flag);
+      }));
 
       await _controller.setBackgroundColor(Colors.transparent);
       await _controller.setPopupWindowPolicy(WebviewPopupWindowPolicy.deny);
@@ -211,4 +223,10 @@ class _ExampleBrowser extends State<ExampleBrowser> {
 
     return decision ?? WebviewPermissionDecision.none;
   }
+
+  @override
+  void dispose() {
+    _subscriptions.forEach((s) => s.cancel());
+    super.dispose();
+  }
 }

example/pubspec.yaml

@@ -12,6 +12,7 @@ dependencies:
 
   webview_windows:
     path: ../
+  window_manager: ^0.2.7
 
 dev_dependencies:
   flutter_test:

lib/src/webview.dart

@@ -143,6 +143,14 @@ class WebviewController extends ValueNotifier<WebviewValue> {
 
   Stream<dynamic> get webMessage => _webMessageStreamController.stream;
 
+  final StreamController<bool>
+      _containsFullScreenElementChangedStreamController =
+      StreamController<bool>.broadcast();
+
+  /// A stream reflecting whether the document currently contains full-screen elements.
+  Stream<bool> get containsFullScreenElementChanged =>
+      _containsFullScreenElementChangedStreamController.stream;
+
   WebviewController() : super(WebviewValue.uninitialized());
 
   /// Initializes the underlying platform view.
@@ -194,6 +202,10 @@ class WebviewController extends ValueNotifier<WebviewValue> {
             } catch (ex) {
               _webMessageStreamController.addError(ex);
             }
+            break;
+          case 'containsFullScreenElementChanged':
+            _containsFullScreenElementChangedStreamController.add(map['value']);
+            break;
         }
       });
 

windows/webview.cc

@@ -358,6 +358,19 @@ void Webview::RegisterEventHandlers() {
           })
           .Get(),
       &event_registrations_.new_windows_requested_token_);
+
+  webview_->add_ContainsFullScreenElementChanged(
+      Callback<ICoreWebView2ContainsFullScreenElementChangedEventHandler>(
+          [this](ICoreWebView2* sender, IUnknown* args) -> HRESULT {
+            BOOL flag = FALSE;
+            if (contains_fullscreen_element_changed_callback_ &&
+                SUCCEEDED(sender->get_ContainsFullScreenElement(&flag))) {
+              contains_fullscreen_element_changed_callback_(flag);
+            }
+            return S_OK;
+          })
+          .Get(),
+      &event_registrations_.contains_fullscreen_element_changed_token_);
 }
 
 void Webview::SetSurfaceSize(size_t width, size_t height) {

windows/webview.h

@@ -86,6 +86,7 @@ struct EventRegistrations {
   EventRegistrationToken permission_requested_token_{};
   EventRegistrationToken devtools_protocol_event_token_{};
   EventRegistrationToken new_windows_requested_token_{};
+  EventRegistrationToken contains_fullscreen_element_changed_token_{};
 };
 
 class Webview {
@@ -113,6 +114,8 @@ class Webview {
                              bool is_user_initiated,
                              WebviewPermissionRequestedCompleter completer)>
       PermissionRequestedCallback;
+  typedef std::function<void(bool contains_fullscreen_element)>
+      ContainsFullScreenElementChangedCallback;
 
   ~Webview();
 
@@ -200,6 +203,11 @@ class Webview {
     devtools_protocol_event_callback_ = std::move(callback);
   }
 
+  void OnContainsFullScreenElementChanged(
+      ContainsFullScreenElementChangedCallback callback) {
+    contains_fullscreen_element_changed_callback_ = std::move(callback);
+  }
+
  private:
   HWND hwnd_;
   bool owns_window_;
@@ -233,6 +241,8 @@ class Webview {
   WebMessageReceivedCallback web_message_received_callback_;
   PermissionRequestedCallback permission_requested_callback_;
   DevtoolsProtocolEventCallback devtools_protocol_event_callback_;
+  ContainsFullScreenElementChangedCallback
+      contains_fullscreen_element_changed_callback_;
 
   Webview(
       wil::com_ptr<ICoreWebView2CompositionController> composition_controller,

windows/webview_bridge.cc

@@ -288,6 +288,16 @@ void WebviewBridge::RegisterEventHandlers() {
              Webview::WebviewPermissionRequestedCompleter completer) {
         OnPermissionRequested(url, kind, is_user_initiated, completer);
       });
+
+  webview_->OnContainsFullScreenElementChanged(
+      [this](bool contains_fullscreen_element) {
+        const auto event = flutter::EncodableValue(flutter::EncodableMap{
+            {flutter::EncodableValue(kEventType),
+             flutter::EncodableValue("containsFullScreenElementChanged")},
+            {flutter::EncodableValue(kEventValue),
+             contains_fullscreen_element}});
+        EmitEvent(event);
+      });
 }
 
 void WebviewBridge::OnPermissionRequested(