feat: flutter增加长按功能

webrtc_controller_flutter/lib/widgets/remote_touch_view.dart

@@ -1,3 +1,4 @@
+import 'dart:async';
 import 'dart:math';
 
 import 'package:flutter/material.dart';
@@ -10,6 +11,7 @@ import 'package:flutter/services.dart';
 ///
 /// - 短时间内位移很小的抬起 -> 单击（TOUCH）
 /// - 否则 -> 滑动（SWIPE）
+/// - 按住不动超过阈值 -> 长按（LONG_PRESS）
 /// 同时捕获物理按键事件（KEY），用于外接键盘 / 遥控器场景。
 ///
 /// 该控件完全基于 Flutter 框架实现，无需任何原生代码，可运行于
@@ -24,12 +26,14 @@ class RemoteTouchView extends StatefulWidget {
     int durationMs,
   ) onSwipe;
   final void Function(int keyCode, int action) onKey;
+  final void Function(double x, double y) onLongPress;
 
   const RemoteTouchView({
     super.key,
     required this.onTouch,
     required this.onSwipe,
     required this.onKey,
+    required this.onLongPress,
   });
 
   @override
@@ -38,7 +42,16 @@ class RemoteTouchView extends StatefulWidget {
 
 class _RemoteTouchViewState extends State<RemoteTouchView> {
   Offset? _startPosition;
+  Offset? _currentPosition;
   DateTime? _startTime;
+  bool _isLongPressed = false;
+  Timer? _longPressTimer;
+
+  /// 长按触发阈值，对应 Android GestureDetector 默认的 LONG_PRESS_TIMEOUT（400ms）。
+  static const _longPressTimeout = Duration(milliseconds: 400);
+
+  /// 手指移动超过该像素阈值则视为滚动，取消长按（对应 Android touch slop）。
+  static const _touchSlop = 10.0;
 
   double _toRelativeX(Offset local, Size size) =>
       (local.dx / size.width).clamp(0.0, 1.0);
@@ -46,6 +59,17 @@ class _RemoteTouchViewState extends State<RemoteTouchView> {
   double _toRelativeY(Offset local, Size size) =>
       (local.dy / size.height).clamp(0.0, 1.0);
 
+  void _cancelLongPress() {
+    _longPressTimer?.cancel();
+    _longPressTimer = null;
+  }
+
+  @override
+  void dispose() {
+    _cancelLongPress();
+    super.dispose();
+  }
+
   @override
   Widget build(BuildContext context) {
     return Focus(
@@ -64,10 +88,39 @@ class _RemoteTouchViewState extends State<RemoteTouchView> {
       child: Listener(
         behavior: HitTestBehavior.opaque,
         onPointerDown: (event) {
+          _cancelLongPress();
+          _isLongPressed = false;
           _startPosition = event.localPosition;
+          _currentPosition = event.localPosition;
           _startTime = DateTime.now();
+          _longPressTimer = Timer(_longPressTimeout, () {
+            final size = context.size;
+            if (_currentPosition == null || size == null) return;
+            _isLongPressed = true;
+            final x = _toRelativeX(_currentPosition!, size);
+            final y = _toRelativeY(_currentPosition!, size);
+            widget.onLongPress(x, y);
+          });
+        },
+        onPointerMove: (event) {
+          _currentPosition = event.localPosition;
+          if (_longPressTimer != null && _startPosition != null) {
+            final dx = (event.localPosition.dx - _startPosition!.dx).abs();
+            final dy = (event.localPosition.dy - _startPosition!.dy).abs();
+            if (dx > _touchSlop || dy > _touchSlop) {
+              _cancelLongPress();
+            }
+          }
         },
         onPointerUp: (event) {
+          _cancelLongPress();
+          // 长按已触发则不再派发单击 / 滑动事件（对应 Android 端 isLongPressed 逻辑）。
+          if (_isLongPressed) {
+            _startPosition = null;
+            _currentPosition = null;
+            _startTime = null;
+            return;
+          }
           final size = context.size;
           if (_startPosition == null || size == null || _startTime == null) {
             return;
@@ -87,6 +140,7 @@ class _RemoteTouchViewState extends State<RemoteTouchView> {
             widget.onSwipe(startX, startY, endX, endY, max(duration, 1));
           }
           _startPosition = null;
+          _currentPosition = null;
           _startTime = null;
         },
         child: const ColoredBox(