Flutter 颤振：IconButton未接收onPressed函数（）
我在下面创建了一个自定义布局：Flutter 颤振：IconButton未接收onPressed函数（）,flutter,Flutter,我在下面创建了一个自定义布局： class CustomLayout extends StatelessWidget { final Widget leading; final String title; final Widget body; final List<Widget> bottomBar; const CustomLayout({ Key key,Widget leading, String title, Widget body, this.
class CustomLayout extends StatelessWidget {
final Widget leading;
final String title;
final Widget body;
final List<Widget> bottomBar;
const CustomLayout({
Key key,Widget leading, String title, Widget body, this.bottomBar
}):leading = leading ?? const SizedBox(height: 0,),
title = title ?? "",
body = body ?? const SizedBox(),
super(key: key)
;
@override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
body: Stack(
alignment: Alignment.topLeft,
children: [
/// Background
Container(
decoration: BoxDecoration(
image: DecorationImage(
image: AssetImage("images/background.jpg"),
fit: BoxFit.cover
)
),
),
/// custom
Column(
children: [
/// SimpleAppbar
SizedBox(
height: (title == "")? 0 : 50,
width: MediaQuery.of(context).size.width,
child: Stack(
alignment: Alignment.centerLeft,
children: [
Center(
child: Text(
title,
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold,
fontSize: 24
),
),
),
Container(
padding: const EdgeInsets.only(left:4.0,top: 4.0),
child: leading,
),
],
),
),
/// body
Expanded(child: body),
/// bottomBar
SizedBox(
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceAround,
children: bottomBar == null ? [SizedBox()]:bottomBar,
),
)
],
)
],
),
),
);
}
}
无法按下前导参数，我搜索并得到了一些提示，这些提示可能是我的堆栈，但我已经检查了很多次。底部栏和主体参数仍然可以正常工作。救救我 通常，堆栈用于分层格式，因此您在自定义布局中使用了扩展到主体，这就是为什么它占据了整个屏幕的宽度和高度，并且位于主图标的顶部，这就是为什么图标从未被按下，所以我在您的布局中更改了一些内容请查看
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
home: SampleApp(),
debugShowCheckedModeBanner: false,
);
}
}
class SampleApp extends StatefulWidget {
@override
_SampleAppState createState() => _SampleAppState();
}
class _SampleAppState extends State<SampleApp> {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Your app'),
),
body: Container(
child: CustomLayout(
leading: IconButton(
icon: Icon(
Icons.arrow_back,
color: Colors.black,
size: 20,
),
onPressed: () {
print('This is the tap');
},
),
body: Text('This is your body') // my code
),
));
}
}
class CustomLayout extends StatelessWidget {
final Widget leading;
final String title;
final Widget body;
final List<Widget> bottomBar;
const CustomLayout(
{Key key, Widget leading, String title, Widget body, this.bottomBar})
: leading = leading ??
const SizedBox(
height: 0,
),
title = title ?? "",
body = body ?? const SizedBox(),
super(key: key);
@override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
body: Container(
child: Stack(
alignment: Alignment.topLeft,
children: [
/// Background
Container(
decoration: BoxDecoration(),
),
/// custom
Column(
children: [
/// SimpleAppbar
SizedBox(
height: (title == "") ? 0 : 50,
width: MediaQuery.of(context).size.width,
child: Stack(
alignment: Alignment.centerLeft,
children: [
Center(
child: Text(
title,
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold,
fontSize: 24),
),
),
],
),
),
/// body
Expanded(child: body),
/// bottomBar
SizedBox(
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceAround,
children: bottomBar == null ? [SizedBox()] : bottomBar,
),
),
],
),
Container(
padding: const EdgeInsets.only(left: 4.0, top: 5.0),
child: leading,
),
],
),
),
),
);
}
}
导入“包装：颤振/材料.省道”；
void main（）=>runApp（MyApp（））；
类MyApp扩展了无状态小部件{
@凌驾
小部件构建（构建上下文）{
返回材料PP(
主页：SampleApp（），
debugShowCheckedModeBanner:false，
);
}
}
类SampleApp扩展StatefulWidget{
@凌驾
_SampleAppState createState（）；
}
类_SampleAppState扩展状态{
@凌驾
小部件构建（构建上下文）{
返回脚手架(
appBar:appBar(
标题：文本（“您的应用程序”），
),
主体：容器(
子：自定义布局(
领先：IconButton(
图标：图标(
Icons.arrow_back，
颜色：颜色，黑色，
尺码：20，
),
已按下：（）{
打印（“这是水龙头”）；
},
),
body:Text（'这是你的body'）//我的代码
),
));
}
}
类CustomLayout扩展了无状态小部件{
最终引导；
最后的字符串标题；
最终窗口小部件主体；
最终列表底部栏；
常量自定义布局(
{键，小部件前导，字符串标题，小部件主体，this.bottomBar}）
：领先=领先？？
常量大小框(
高度:0,，
),
标题=标题？？“，
body=body？？const SizedBox（），
超级（键：键）；
@凌驾
小部件构建（构建上下文）{
返回安全区(
孩子：脚手架(
主体：容器(
子：堆栈(
对齐：alignment.topLeft，
儿童：[
///背景
容器(
装饰：BoxDecoration（），
),
///习俗
纵队(
儿童：[
///SimpleAppbar
大小盒子(
高度：（标题==”）？0:50，
宽度：MediaQuery.of（context）.size.width，
子：堆栈(
对齐：alignment.centerLeft，
儿童：[
居中(
子：文本(
标题
样式：TextStyle(
颜色：颜色，白色，
fontWeight:fontWeight.bold，
尺寸:24),，
),
),
],
),
),
///身体
扩展（子：体），
///底线
大小盒子(
孩子：排(
mainAxisAlignment:mainAxisAlignment.spaceAround，
子项：bottomBar==null？[SizedBox（）]：bottomBar，
),
),
],
),
容器(
填充：仅限常量边集（左：4.0，顶：5.0），
孩子：领导，
),
],
),
),
),
);
}
}
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
home: SampleApp(),
debugShowCheckedModeBanner: false,
);
}
}
class SampleApp extends StatefulWidget {
@override
_SampleAppState createState() => _SampleAppState();
}
class _SampleAppState extends State<SampleApp> {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Your app'),
),
body: Container(
child: CustomLayout(
leading: IconButton(
icon: Icon(
Icons.arrow_back,
color: Colors.black,
size: 20,
),
onPressed: () {
print('This is the tap');
},
),
body: Text('This is your body') // my code
),
));
}
}
class CustomLayout extends StatelessWidget {
final Widget leading;
final String title;
final Widget body;
final List<Widget> bottomBar;
const CustomLayout(
{Key key, Widget leading, String title, Widget body, this.bottomBar})
: leading = leading ??
const SizedBox(
height: 0,
),
title = title ?? "",
body = body ?? const SizedBox(),
super(key: key);
@override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
body: Container(
child: Stack(
alignment: Alignment.topLeft,
children: [
/// Background
Container(
decoration: BoxDecoration(),
),
/// custom
Column(
children: [
/// SimpleAppbar
SizedBox(
height: (title == "") ? 0 : 50,
width: MediaQuery.of(context).size.width,
child: Stack(
alignment: Alignment.centerLeft,
children: [
Center(
child: Text(
title,
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold,
fontSize: 24),
),
),
],
),
),
/// body
Expanded(child: body),
/// bottomBar
SizedBox(
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceAround,
children: bottomBar == null ? [SizedBox()] : bottomBar,
),
),
],
),
Container(
padding: const EdgeInsets.only(left: 4.0, top: 5.0),
child: leading,
),
],
),
),
),
);
}
}