在Flutter中,确实可以像这样做。您可以使用Column Widget,并将其第一个子项设置为标题栏或类似的内容,其中包含标题和返回箭头图标。
以下是相应的代码:
import 'dart:async';
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData(
canvasColor: Colors.transparent,
),
home: MyHomePage(),
);
}
}
class MyHomePage extends StatefulWidget{
@override
HomePageS createState()=> HomePageS();
}
class HomePageS extends State<MyHomePage>{
@override
Widget build(BuildContext context){
return Scaffold(
body: Container(
color: Colors.white,
child: Center(
child: FlatButton(
child: Text("Show BottomSheet"),
onPressed: () async{
showModalBottomSheet(
context: context,
builder: (BuildContext context){
return ClipRRect(
borderRadius: BorderRadius.only(topLeft: Radius.circular(20.0), topRight: Radius.circular(20.0)),
child: Container(
color: Colors.white,
child: Column(
children: [
ListTile(
leading: Material(
color: Colors.transparent,
child: InkWell(
onTap: (){
Navigator.of(context).pop();
},
child: Icon(Icons.arrow_back) // the arrow back icon
),
),
title: Center(
child: Text("My Title") // Your desired title
)
),
]
)
)
);
}
);
}
)
)
)
);
}
}
这是输出结果:
如果你不想使用InkWell小部件,你可以像这样使用IconButton小部件:
...
ListTile(
leading: IconButton(
icon: Icon(Icons.arrow_back),
onPressed: (){
Navigator.of(context).pop();
}
),
title: Center(
child: Text("My Title")
)
),
...
但是如果你注意到了,标题文本实际上并没有居中显示。在这种情况下,我们可以将ListTile小部件替换为Stack小部件,并像这样操作:
child: Column(
children: [
Stack(
children: [
Container(
width: double.infinity,
height: 56.0,
child: Center(
child: Text("My Title") // Your desired title
),
),
Positioned(
left: 0.0,
top: 0.0,
child: IconButton(
icon: Icon(Icons.arrow_back), // Your desired icon
onPressed: (){
Navigator.of(context).pop();
}
)
)
]
),
]
)
...
这是输出内容:
但如果我们的标题非常长,会发生什么?它肯定会看起来像这样:
很丑,是吧?我们可以看到我们的文本小部件与我们的 IconButton 小部件重叠了。为了避免这种情况,我们可以用 Row 小部件替换我们的 Stack 小部件。
以下是代码:
...
child: Column(
children: [
Row( // A Row widget
mainAxisAlignment: MainAxisAlignment.spaceBetween, // Free space will be equally divided and will be placed between the children.
children: [
IconButton( // A normal IconButton
icon: Icon(Icons.arrow_back),
onPressed: (){
Navigator.of(context).pop();
}
),
Flexible( // A Flexible widget that will make its child flexible
child: Text(
"My Title is very very very very very very very long", // A very long text
overflow: TextOverflow.ellipsis, // handles overflowing of text
),
),
Opacity( // A Opacity widget
opacity: 0.0, // setting opacity to zero will make its child invisible
child: IconButton(
icon: Icon(Icons.clear), // some random icon
onPressed: null, // making the IconButton disabled
)
),
]
),
]
)
输出结果将会是这样:
如果标题不是很长,则会是这样:
我想我的解决方案可能有些幼稚,但对我来说完美地解决了问题。你也可以尝试一下。
showModalBottomSheet(
barrierColor: Colors.transparent,
enableDrag: true,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.vertical(top: Radius.circular(20))),
context: context,
builder:(context){
return Padding(
padding: const EdgeInsets.only(left: 8.0, right: 8.0, bottom: 8.0),
child: Stack(children: [
Padding(
padding: const EdgeInsets.only(top: 65),
child: SingleChildScrollView(
child:<<Scrollable Wdgets>>,
),
),
Card(
elevation: 3,
color: Colors.grey[850],
child: ListTile(
leading: Text("YOUR TITLE",
style: TextStyle(
color: Colors.white,
fontSize: 20,
fontWeight: FontWeight.w500)),
trailing: GestureDetector(
onTap: () {
Navigator.pop(context);
},
child: Icon(
Icons.close,
color: Colors.white,
size: 20,
),
),
),
),
]),
);}