[trtc][flutter] Add Windows screen sharing functionality

TRTC-Simple-Demo/lib/ui/bgra_image.dart

@@ -0,0 +1,70 @@
+import 'dart:async';
+import 'dart:typed_data';
+import 'dart:ui' as ui;
+import 'package:flutter/material.dart';
+
+class BgraImage extends StatefulWidget {
+  final Uint8List? bgraData;
+  final int width;
+  final int height;
+
+  BgraImage({
+    Key? key,
+    required this.bgraData,
+    required this.width,
+    required this.height,
+  }) : super(key: key);
+
+  @override
+  _BgraImageState createState() => _BgraImageState();
+}
+
+class _BgraImageState extends State<BgraImage> {
+  late Future<ui.Image?> _imageFuture;
+
+  @override
+  void initState() {
+    super.initState();
+    if (widget.bgraData != null) {
+      _imageFuture = _bgraToImage(widget.bgraData!, widget.width, widget.height);
+    } else {
+      _imageFuture = Future.value(null);
+    }
+  }
+
+  Future<ui.Image?> _bgraToImage(Uint8List bgraData, int width, int height) async {
+    final completer = Completer<ui.Image>();
+
+    ui.decodeImageFromPixels(
+      bgraData,
+      width,
+      height,
+      ui.PixelFormat.bgra8888,
+      (ui.Image image) {
+        completer.complete(image);
+      },
+    );
+
+    return completer.future;
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return FutureBuilder<ui.Image?>(
+      future: _imageFuture,
+      builder: (BuildContext context, AsyncSnapshot<ui.Image?> snapshot) {
+        if (snapshot.connectionState == ConnectionState.done) {
+          if (snapshot.data != null) {
+            return RawImage(
+              image: snapshot.data!,
+            );
+          } else {
+            return Container(color: Colors.black);
+          }
+        } else {
+          return CircularProgressIndicator();
+        }
+      },
+    );
+  }
+}

TRTC-Simple-Demo/lib/ui/meeting.dart

@@ -19,6 +19,7 @@ import 'package:trtc_demo/ui/login.dart';
 import 'package:trtc_demo/models/meeting_model.dart';
 import 'package:trtc_demo/debug/GenerateTestUserSig.dart';
 import 'package:provider/provider.dart';
+import 'package:trtc_demo/ui/window_dialog.dart';
 import 'package:replay_kit_launcher/replay_kit_launcher.dart';
 
 const iosAppGroup = 'group.com.tencent.comm.trtc.demo';
@@ -349,20 +350,53 @@ class MeetingPageState extends State<MeetingPage> with WidgetsBindingObserver {
           _meetModel.getUserInfo().isOpenCamera = true;
         });
       }
-    } else if (!kIsWeb && (Platform.isWindows || Platform.isMacOS)) {
+    } else if (!kIsWeb && Platform.isMacOS) {
       MeetingTool.toast(
           'The current platform does not support screen sharing.', context);
       return;
+    } else if (!kIsWeb && Platform.isWindows) {
+      if (!_meetModel.getUserInfo().isShowingWindow) {
+        TRTCScreenCaptureSourceList list = await _trtcCloud.getScreenCaptureSources(thumbnailWidth: 100, thumbnailHeight: 100, iconWidth: 100, iconHeight: 100);
+        showWindowSelector(context, list);
+      } else {
+        await _trtcCloud.stopScreenCapture();
+        _userList[0].isOpenCamera = true;
+        _trtcCloud.startLocalPreview(
+            _meetModel.getUserInfo().isFrontCamera, _meetModel.getUserInfo().localViewId);
+        this.setState(() {
+          _meetModel.getUserInfo().isShowingWindow = false;
+          _meetModel.getUserInfo().isOpenCamera = true;
+        });
+      }
     } else {
       await _startShare();
-      //The screen sharing function can only be tested on the real machine
+      // The screen sharing function can only be tested on the real machine
       ReplayKitLauncher.launchReplayKitBroadcast(iosExtensionName);
       this.setState(() {
         _meetModel.getUserInfo().isOpenCamera = false;
       });
     }
   }
 
+  void showWindowSelector(BuildContext context, TRTCScreenCaptureSourceList windows) async {
+    final result = await showDialog<int>(
+      context: context,
+      builder: (BuildContext context) {
+        return WindowSelectorDialog(windows: windows);
+      },
+  );
+
+  if (result != null) {
+    print('Selected window index: $result');
+    await _trtcCloud.selectScreenCaptureTarget(windows.sourceInfo[result], TRTCScreenCaptureProperty());
+        await _startShare();
+        this.setState(() {
+          _meetModel.getUserInfo().isShowingWindow = true;
+          _meetModel.getUserInfo().isOpenCamera = false;
+        });
+  }
+}
+
   Widget _renderView(UserModel item, valueKey, width, height) {
     if (item.isOpenCamera) {
       return GestureDetector(

TRTC-Simple-Demo/lib/ui/window_dialog.dart

@@ -0,0 +1,58 @@
+
+import 'package:tencent_trtc_cloud/trtc_cloud_def.dart';
+import 'package:flutter/material.dart';
+
+import 'package:trtc_demo/ui/bgra_image.dart';
+
+class WindowSelectorDialog extends StatelessWidget {
+  final TRTCScreenCaptureSourceList windows;
+
+  WindowSelectorDialog({required this.windows});
+
+  @override
+  Widget build(BuildContext context) {
+    return AlertDialog(
+      title: Text('Select a window to share'),
+      content: Container(
+        width: double.maxFinite,
+                child: GridView.builder(
+          itemCount: windows.count,
+          gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
+            crossAxisCount: 5, 
+            crossAxisSpacing: 8, 
+            mainAxisSpacing: 8, 
+            childAspectRatio: 1, 
+          ),
+          itemBuilder: (context, index) {
+            final window = windows.sourceInfo[index];
+            final imageBuffer = (window.type == TRTCScreenCaptureSourceType.window)
+                ? window.iconBGRA
+                : window.thumbBGRA;
+            return InkWell(
+              onTap: () {
+                Navigator.of(context).pop(index);
+              },
+              child: Column(
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  Text(
+                    window.sourceName!,
+                    style: TextStyle(fontSize: 12),
+                  ),
+                  SizedBox(height: 8),
+                  imageBuffer != null
+                      ? BgraImage(
+                          bgraData: imageBuffer.buffer!,
+                          width: imageBuffer.width!,
+                          height: imageBuffer.height!,
+                        )
+                      : Placeholder(fallbackWidth: 50, fallbackHeight: 50),
+                ],
+              ),
+            );
+          },
+        ),
+      ),
+    );
+  }
+}