Flutter:当GestureDetector中具有ListView时，显然没有收到Drag事件 [英] Flutter: GestureDetector apparently doesn't receive Drag events when it has a ListView in it

问题描述

我错过了什么吗?该文档说，事件从最内层的孩子到祖先冒泡，但是下面的代码不会在控制台上打印".它确实打印点击". 将NeverScrollablePhyiscs应用于ListView确实可以，但是我想在两个级别上监听该事件.将HitTestBehavior.translucent应用于GestureDetector不会改变任何内容.

Am I missing something? The documentation says that events bubble up from the innermost child to the ancestors, but below code will not print "dragged" to the console. It does print "tapped" though. Applying NeverScrollablePhyiscs to the ListView does work, but i want to listen on the event on both levels. Applying HitTestBehavior.translucent to the GestureDetector doesn't change anything.

import "package:flutter/material.dart";

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
    Widget build(BuildContext context) {
      return MaterialApp(
        home: MyHomePage(),
      );
    }
}

class MyHomePage extends StatelessWidget {
  @override
    Widget build(BuildContext context) {
      return Scaffold(
        body: GestureDetector(
          onVerticalDragUpdate: (DragUpdateDetails details) {
            print("dragged");
          },
          onTap: () {
            print("tapped");
          },
          child: ListView.builder(
            itemBuilder: (context, index) {
              return Container(
                padding: EdgeInsets.all(20.0),
                child: Text(
                  "The GestureDetector above me does not react to drag events. Maybe my parent is at fault?"
                )
              );
            },
          )
        )
      );
    }
}

推荐答案

您可以使用Listener

      return Scaffold(
            body: Listener(onPointerMove: (opm) {
              print("onPointerMove .. ${opm.position}");
        }, child: ListView.builder(
          itemBuilder: (context, index) {
            return Container(
                padding: EdgeInsets.all(20.0),
                child: Text(
                    "The GestureDetector above me does not react to drag events. Maybe my parent is at fault?"));
          },
        )));

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