Flutter手势识别插件swipe_gesture_recognizer的使用

swipe_gesture_recognizer是一个简单且轻量级的 Flutter 小部件，用于检测滑动手势。它可以识别四种滑动方向：向上、向下、向左和向右。

特性

• 检测四种滑动手势：swipe up、swipe down、swipe left 和 swipe right。

开始使用

要开始使用 swipe_gesture_recognizer，首先需要将其作为子部件传递给目标小部件，并为所需的滑动方向声明回调函数。

示例代码

以下是一个完整的示例代码，展示了如何使用 swipe_gesture_recognizer 来检测滑动手势：

import 'package:flutter/material.dart';
import 'package:swipe_gesture_recognizer/swipe_gesture_recognizer.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
      home: SwipeGestureExample(),
    );
  }
}

class SwipeGestureExample extends StatefulWidget {
  [@override](/user/override)
  _SwipeGestureExampleState createState() => _SwipeGestureExampleState();
}

class _SwipeGestureExampleState extends State<SwipeGestureExample> {
  String message = "滑动方向未检测到";

  void _onSwipeLeft() {
    setState(() {
      message = "向左滑动";
    });
  }

  void _onSwipeRight() {
    setState(() {
      message = "向右滑动";
    });
  }

  void _onSwipeUp() {
    setState(() {
      message = "向上滑动";
    });
  }

  void _onSwipeDown() {
    setState(() {
      message = "向下滑动";
    });
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Swipe Gesture Recognizer 示例"),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Text(
              message,
              style: TextStyle(fontSize: 20),
            ),
            SizedBox(height: 20),
            SwipeGestureRecognizer(
              child: Container(
                width: 200,
                height: 200,
                color: Colors.blue,
                child: Center(
                  child: Text(
                    "滑动这里",
                    style: TextStyle(color: Colors.white),
                  ),
                ),
              ),
              onSwipeLeft: _onSwipeLeft,
              onSwipeRight: _onSwipeRight,
              onSwipeUp: _onSwipeUp,
              onSwipeDown: _onSwipeDown,
            ),
          ],
        ),
      ),
    );
  }
}

代码说明

1. 导入库：

   import 'package:swipe_gesture_recognizer/swipe_gesture_recognizer.dart';
   

   导入 swipe_gesture_recognizer 库以便使用其功能。

2. 定义主应用：

   void main() {
     runApp(MyApp());
   }
   

3. 创建主小部件：

   class MyApp extends StatelessWidget {
     [@override](/user/override)
     Widget build(BuildContext context) {
       return MaterialApp(
         home: SwipeGestureExample(),
       );
     }
   }
   

4. 定义状态类：

   class _SwipeGestureExampleState extends State<SwipeGestureExample> {
     String message = "滑动方向未检测到";
   
     void _onSwipeLeft() {
       setState(() {
         message = "向左滑动";
       });
     }
   
     void _onSwipeRight() {
       setState(() {
         message = "向右滑动";
       });
     }
   
     void _onSwipeUp() {
       setState(() {
         message = "向上滑动";
       });
     }
   
     void _onSwipeDown() {
       setState(() {
         message = "向下滑动";
       });
     }
   

5. 构建 UI：

   [@override](/user/override)
   Widget build(BuildContext context) {
     return Scaffold(
       appBar: AppBar(
         title: Text("Swipe Gesture Recognizer 示例"),
       ),
       body: Center(
         child: Column(
           mainAxisAlignment: MainAxisAlignment.center,
           children: [
             Text(
               message,
               style: TextStyle(fontSize: 20),
             ),
             SizedBox(height: 20),
             SwipeGestureRecognizer(
               child: Container(
                 width: 200,
                 height: 200,
                 color: Colors.blue,
                 child: Center(
                   child: Text(
                     "滑动这里",
                     style: TextStyle(color: Colors.white),
                   ),
                 ),
               ),
               onSwipeLeft: _onSwipeLeft,
               onSwipeRight: _onSwipeRight,
               onSwipeUp: _onSwipeUp,
               onSwipeDown: _onSwipeDown,
             ),
           ],
         ),
       ),
     );
   }