我用TextFormField收集用户输入，当用户按下FloatingActionButton表示他们已经完成时，我想解散屏幕上的键盘。
如何让键盘自动消失?
import 'package:flutter/material.dart';
class MyHomePage extends StatefulWidget {
MyHomePageState createState() => new MyHomePageState();
}
class MyHomePageState extends State<MyHomePage> {
TextEditingController _controller = new TextEditingController();
@override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(),
floatingActionButton: new FloatingActionButton(
child: new Icon(Icons.send),
onPressed: () {
setState(() {
// send message
// dismiss on screen keyboard here
_controller.clear();
});
},
),
body: new Container(
alignment: FractionalOffset.center,
padding: new EdgeInsets.all(20.0),
child: new TextFormField(
controller: _controller,
decoration: new InputDecoration(labelText: 'Example Text'),
),
),
);
}
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return new MaterialApp(
home: new MyHomePage(),
);
}
}
void main() {
runApp(new MyApp());
}
在Flutter中，一切都是一个小部件，我决定包装FocusScope.of(context).unfocus();在一个简短的实用程序小部件中实现。
只需创建KeyboardHider小部件:
import 'package:flutter/widgets.dart';
/// A widget that upon tap attempts to hide the keyboard.
class KeyboardHider extends StatelessWidget {
/// Creates a widget that on tap, hides the keyboard.
const KeyboardHider({
required this.child,
Key? key,
}) : super(key: key);
/// The widget below this widget in the tree.
final Widget child;
@override
Widget build(BuildContext context) {
return GestureDetector(
behavior: HitTestBehavior.opaque,
onTap: () => FocusScope.of(context).unfocus(),
child: child,
);
}
}
现在，您可以用KeyboardHider小部件包装任何小部件(在使用好的IDE时非常方便)，然后当您点击某个东西时，键盘将自动关闭。它与表单和其他可点击区域一起工作得很好。
class SimpleWidget extends StatelessWidget {
@override
Widget build(BuildContext context) {
return KeyboardHider(
/* Here comes a widget tree that eventually opens the keyboard,
* but the widget that opened the keyboard doesn't necessarily
* takes care of hiding it, so we wrap everything in a
* KeyboardHider widget */
child: Container(),
);
}
}
您可以使用FocusNode类中的unfocus()方法。
import 'package:flutter/material.dart';
class MyHomePage extends StatefulWidget {
MyHomePageState createState() => new MyHomePageState();
}
class MyHomePageState extends State<MyHomePage> {
TextEditingController _controller = new TextEditingController();
FocusNode _focusNode = new FocusNode(); //1 - declare and initialize variable
@override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(),
floatingActionButton: new FloatingActionButton(
child: new Icon(Icons.send),
onPressed: () {
_focusNode.unfocus(); //3 - call this method here
},
),
body: new Container(
alignment: FractionalOffset.center,
padding: new EdgeInsets.all(20.0),
child: new TextFormField(
controller: _controller,
focusNode: _focusNode, //2 - assign it to your TextFormField
decoration: new InputDecoration(labelText: 'Example Text'),
),
),
);
}
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return new MaterialApp(
home: new MyHomePage(),
);
}
}
void main() {
runApp(new MyApp());
}
