在Android开发中 EditTextView 复制直接调用setText()方法即可，那么在flutter中我遍历所有TextField 属性后发现没有setText这个方法！很困惑
所有属性如下：
const TextField({
Key key,
this.controller, //编辑框的控制器，跟文本框的交互一般都通过该属性完成，如果不创建的话默认会自动创建
this.focusNode, //用于管理焦点
this.decoration = const InputDecoration(), //输入框的装饰器，用来修改外观
TextInputType keyboardType, //设置输入类型，不同的输入类型键盘不一样
this.textInputAction, //用于控制键盘动作（一般位于右下角，默认是完成）
this.textCapitalization = TextCapitalization.none,
this.style, //输入的文本样式
this.textAlign = TextAlign.start, //输入的文本位置
this.textDirection, //输入的文字排列方向，一般不会修改这个属性
this.autofocus = false, //是否自动获取焦点
this.obscureText = false, //是否隐藏输入的文字，一般用在密码输入框中
this.autocorrect = true, //是否自动校验
this.maxLines = 1, //最大行
this.maxLength, //能输入的最大字符个数
this.maxLengthEnforced = true, //配合maxLength一起使用，在达到最大长度时是否阻止输入
this.onChanged, //输入文本发生变化时的回调
this.onEditingComplete, //点击键盘完成按钮时触发的回调，该回调没有参数，(){}
this.onSubmitted, //同样是点击键盘完成按钮时触发的回调，该回调有参数，参数即为当前输入框中的值。(String){}
this.inputFormatters, //对输入文本的校验
this.enabled, //输入框是否可用
this.cursorWidth = 2.0, //光标的宽度
this.cursorRadius, //光标的圆角
this.cursorColor, //光标的颜色
this.keyboardAppearance,
this.scrollPadding = const EdgeInsets.all(20.0),
this.dragStartBehavior = DragStartBehavior.down,
this.enableInteractiveSelection,
this.onTap, //点击输入框时的回调(){}
this.buildCounter,
})
仔细看这个所有属性的话你会发现
controller：//编辑框的控制器，跟文本框的交互一般都通过该属性完成，如果不创建的话默认会自动创建
给 _controller.value重新赋值就可以实现给TextField 赋值
final _controller = TextEditingController();
_controller.value = _controller.value.copyWith(
text: text,
selection:
TextSelection(baseOffset: text.length, extentOffset: text.length),
composing: TextRange.empty,
);
});
完整代码
// Flutter code sample for widgets.TextEditingController.1
// This example creates a [TextField] with a [TextEditingController] whose
// change listener forces the entered text to be lower case and keeps the
// cursor at the end of the input.
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
/// This Widget is the main application widget.
class MyApp extends StatelessWidget {
static const String _title = 'Flutter Code Sample';
@override
Widget build(BuildContext context) {
return MaterialApp(
title: _title,
home: MyStatefulWidget(),
);
}
}
class MyStatefulWidget extends StatefulWidget {
MyStatefulWidget({Key key}) : super(key: key);
@override
_MyStatefulWidgetState createState() => _MyStatefulWidgetState();
}
class _MyStatefulWidgetState extends State<MyStatefulWidget> {
final _controller = TextEditingController();
void initState() {
_controller.addListener(() {
final text = _controller.text.toLowerCase();
_controller.value = _controller.value.copyWith(
text: text,
selection:
TextSelection(baseOffset: text.length, extentOffset: text.length),
composing: TextRange.empty,
);
});
super.initState();
}
void dispose() {
_controller.dispose();
super.dispose();
}
Widget build(BuildContext context) {
return Scaffold(
body: Container(
alignment: Alignment.center,
padding: const EdgeInsets.all(6),
child: TextFormField(
controller: _controller,
decoration: InputDecoration(border: OutlineInputBorder()),
),
),
);
}
}
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