flutter - Flutter使触摸事件通过AppBar传递

Question

需要我的透明AppBar来允许触摸事件通过，但不能使用抽屉导航按钮。我希望用户能够滚动列表，无论它们位于设备屏幕的顶部。如果在AppBar下面运行代码，则手指在appBar上时会阻止touchDown。

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  final appTitle = '';

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: appTitle,
      home: MyHomePage(title: appTitle),
    );
  }
}

class MyHomePage extends StatelessWidget {
  final String title;

  MyHomePage({Key key, this.title}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      extendBodyBehindAppBar: true,
      backgroundColor: Colors.purple,
      appBar: AppBar( title:Text(title), elevation: 0.0, backgroundColor: Colors.red.withOpacity(0.0)),
      body: Center(child: ListView(
  padding: const EdgeInsets.all(0),
  children: <Widget>[
    Container(
      height: 50,
      color: Colors.amber[600],
      child: const Center(child: Text('Entry A')),
    ),
    Container(
      height: 50,
      color: Colors.amber[500],
      child: const Center(child: Text('Entry B')),
    ),
    Container(
      height: 50,
      color: Colors.amber[100],
      child: const Center(child: Text('Entry C')),
    ),
    Container(
      height: 50,
      color: Colors.amber[600],
      child: const Center(child: Text('Entry A')),
    ),
    Container(
      height: 50,
      color: Colors.amber[500],
      child: const Center(child: Text('Entry B')),
    ),
    Container(
      height: 50,
      color: Colors.amber[100],
      child: const Center(child: Text('Entry C')),
    ),
    Container(
      height: 50,
      color: Colors.amber[600],
      child: const Center(child: Text('Entry A')),
    ),
    Container(
      height: 50,
      color: Colors.amber[500],
      child: const Center(child: Text('Entry B')),
    ),
    Container(
      height: 50,
      color: Colors.amber[100],
      child: const Center(child: Text('Entry C')),
    ),
    Container(
      height: 50,
      color: Colors.amber[600],
      child: const Center(child: Text('Entry A')),
    ),
    Container(
      height: 50,
      color: Colors.amber[500],
      child: const Center(child: Text('Entry B')),
    ),
    Container(
      height: 50,
      color: Colors.amber[100],
      child: const Center(child: Text('Entry C')),
    ),
    Container(
      height: 50,
      color: Colors.amber[600],
      child: const Center(child: Text('Entry A')),
    ),
    Container(
      height: 50,
      color: Colors.amber[500],
      child: const Center(child: Text('Entry B')),
    ),
    Container(
      height: 50,
      color: Colors.amber[100],
      child: const Center(child: Text('Entry C')),
    ),
    Container(
      height: 50,
      color: Colors.amber[600],
      child: const Center(child: Text('Entry A')),
    ),
    Container(
      height: 50,
      color: Colors.amber[500],
      child: const Center(child: Text('Entry B')),
    ),
    Container(
      height: 50,
      color: Colors.amber[100],
      child: const Center(child: Text('Entry C')),
    ),
    Container(
      height: 50,
      color: Colors.amber[600],
      child: const Center(child: Text('Entry A')),
    ),
    Container(
      height: 50,
      color: Colors.amber[500],
      child: const Center(child: Text('Entry B')),
    ),
    Container(
      height: 50,
      color: Colors.amber[100],
      child: const Center(child: Text('Entry C')),
    ),
  ],
)),
      drawer: Drawer(
        // Add a ListView to the drawer. This ensures the user can scroll
        // through the options in the drawer if there isn't enough vertical
        // space to fit everything.
        child: ListView(
          // Important: Remove any padding from the ListView.
          padding: EdgeInsets.zero,
          children: <Widget>[
            DrawerHeader(
              child: Text('Drawer Header'),
              decoration: BoxDecoration(
                color: Colors.blue,
              ),
            ),
            ListTile(
              title: Text('Item 1'),
              onTap: () {
                // Update the state of the app
                // ...
                // Then close the drawer
                Navigator.pop(context);
              },
            ),
            ListTile(
              title: Text('Item 2'),
              onTap: () {
                // Update the state of the app
                // ...
                // Then close the drawer
                Navigator.pop(context);
              },
            ),
          ],
        ),
      ),
    );
  }
}

Answer 1

我以为您不想要AppBar，这就是为什么要使其透明；不知道。

但是，如果您不想要它，但仍然想要左上角的“抽屉菜单”按钮，则可以使用Stack来实现此目的

像这样

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  final appTitle = '';

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: appTitle,
      home: MyHomePage(title: appTitle),
    );
  }
}

class MyHomePage extends StatelessWidget {
  final String title;

  MyHomePage({Key key, this.title}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      extendBodyBehindAppBar: true,
      backgroundColor: Colors.purple,
      body: Stack(
        children: [
          Center(
            child: ListView(
              padding: const EdgeInsets.all(0),
              children: <Widget>[
                Container(
                  height: 50,
                  color: Colors.amber[600],
                  child: const Center(child: Text('Entry A')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[500],
                  child: const Center(child: Text('Entry B')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[100],
                  child: const Center(child: Text('Entry C')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[600],
                  child: const Center(child: Text('Entry A')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[500],
                  child: const Center(child: Text('Entry B')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[100],
                  child: const Center(child: Text('Entry C')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[600],
                  child: const Center(child: Text('Entry A')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[500],
                  child: const Center(child: Text('Entry B')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[100],
                  child: const Center(child: Text('Entry C')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[600],
                  child: const Center(child: Text('Entry A')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[500],
                  child: const Center(child: Text('Entry B')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[100],
                  child: const Center(child: Text('Entry C')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[600],
                  child: const Center(child: Text('Entry A')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[500],
                  child: const Center(child: Text('Entry B')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[100],
                  child: const Center(child: Text('Entry C')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[600],
                  child: const Center(child: Text('Entry A')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[500],
                  child: const Center(child: Text('Entry B')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[100],
                  child: const Center(child: Text('Entry C')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[600],
                  child: const Center(child: Text('Entry A')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[500],
                  child: const Center(child: Text('Entry B')),
                ),
                Container(
                  height: 50,
                  color: Colors.amber[100],
                  child: const Center(child: Text('Entry C')),
                ),
              ],
            ),
          ),
          Positioned(
            top: 10,
            child: Builder(
              builder: (context) {
                return IconButton(
                  color: Colors.white,
                  icon: Icon(Icons.menu),
                  onPressed: (){
                    Scaffold.of(context).openDrawer();
                  },
                );
              }
            ),
          )
        ],
      ),
      drawer: Drawer(
        // Add a ListView to the drawer. This ensures the user can scroll
        // through the options in the drawer if there isn't enough vertical
        // space to fit everything.
        child: ListView(
          // Important: Remove any padding from the ListView.
          padding: EdgeInsets.zero,
          children: <Widget>[
            DrawerHeader(
              child: Text('Drawer Header'),
              decoration: BoxDecoration(
                color: Colors.blue,
              ),
            ),
            ListTile(
              title: Text('Item 1'),
              onTap: () {
                // Update the state of the app
                // ...
                // Then close the drawer
                Navigator.pop(context);
              },
            ),
            ListTile(
              title: Text('Item 2'),
              onTap: () {
                // Update the state of the app
                // ...
                // Then close the drawer
                Navigator.pop(context);
              },
            ),
          ],
        ),
      ),
    );
  }
}