Flutter控件之TextField详解

这是我爱模板网摘抄自简书的一篇对flutter TextFiled文本输入框非常详细的一篇文章：

构造方法

const TextField({
    Key key,
    this.controller,           ////控制器，控制TextField文字
    this.focusNode,
    this.decoration = const InputDecoration(),    //输入器装饰
    TextInputType keyboardType,   ////输入的类型
    this.textInputAction,
    this.textCapitalization = TextCapitalization.none,
    this.style,
    this.textAlign = TextAlign.start,   //文字显示位置
    this.autofocus = false,
    this.obscureText = false,
    this.autocorrect = true,
    this.maxLines = 1,
    this.maxLength,
    this.maxLengthEnforced = true,
    this.onChanged,                //文字改变触发
    this.onEditingComplete,
    this.onSubmitted,   ////文字提交触发（键盘按键）
    this.inputFormatters,
    this.enabled,
    this.cursorWidth = 2.0,
    this.cursorRadius,
    this.cursorColor,
    this.keyboardAppearance,
    this.scrollPadding = const EdgeInsets.all(20.0),
})

1.decoration
输入器装饰

const InputDecoration({
    this.icon,
    this.labelText,
    this.labelStyle,
    this.helperText,
    this.helperStyle,
    this.hintText,
    this.hintStyle,
    this.errorText,
    this.errorStyle,
    this.errorMaxLines,
    this.isDense,
    this.contentPadding,
    this.prefixIcon,
    this.prefix,
    this.prefixText,
    this.prefixStyle,
    this.suffixIcon,
    this.suffix,
    this.suffixText,
    this.suffixStyle,
    this.counterText,
    this.counterStyle,
    this.filled,
    this.fillColor,
    this.errorBorder,
    this.focusedBorder,
    this.focusedErrorBorder,
    this.disabledBorder,
    this.enabledBorder,
    this.border,
    this.enabled = true,
    this.semanticCounterText,
})

①labelText

labelText: '请你输入姓名',
labelStyle: new TextStyle( fontSize: 13.0, color: Colors.amberAccent),

效果如图：

无焦点


有焦点


②hintText
    和android正常hint一样

hintText: '请输入姓名',
hintStyle: new TextStyle(fontSize: 13.0, color: Colors.pink),

如图


③errorText和helperText
    提示性的文本

labelText: '请你输入姓名',
labelStyle: new TextStyle( fontSize: 13.0, color: Colors.amberAccent),
helperText: '嘻嘻嘻',

④icon
    icon可以是自带的Icon也可以是自己的图片

//  icon: new Image.asset('images/goods_image.png', width: 30.0, height: 30.0,),
    icon: new Icon(Icons.person),
    labelText: '请你输入姓名',
    labelStyle: new TextStyle(fontSize: 13.0, color: Colors.amberAccent),
    helperText: '嘻嘻嘻',

⑤contentPadding
    内容的边距，默认是有一个边距的

//  icon: new Image.asset('images/goods_image.png', width: 30.0, height: 30.0,),
    icon: new Icon(Icons.person),
    labelText: '请你输入姓名',
    labelStyle: new TextStyle(fontSize: 13.0, color: Colors.amberAccent),
    helperText: '嘻嘻嘻',
    contentPadding: new EdgeInsets.all(0.0)

⑥prefixIcon
在上面的代码基础之上加下面的代码

prefixIcon: new Icon(Icons.people)

⑦prefixText（同上---icon换成文本）
    prifix(同上一样，他的参数是widget，可以是文本，图片，图片文本的组合container，自己随便组合)

⑧suffixText，suffixIcon，suffix （后缀，用法同prefix一样）

⑨border
    InputBorder.none--------------无border，下划线也没了
    UnderlineInputBorder--------下划线
    OutlineInputBorder-----------周围都有border，一个框


2. TextInputType keyboardType
    键盘输入类型（数字，文本等各种类型）

3. controller
    文本控制器

import 'package:flutter/material.dart';

class FourPage extends StatelessWidget {
  //手机号的控制器
  TextEditingController phoneController = TextEditingController();
  //密码的控制器
  TextEditingController passController = TextEditingController();

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(title: new Text('第四个界面'),),
      body: new Container(
//        color: Colors.pink,
        margin: new EdgeInsets.all(10.0),
        child: new Column(
        children: <Widget>[
          TextField(
          controller: phoneController,
          keyboardType: TextInputType.number,
          decoration: InputDecoration(
            contentPadding: EdgeInsets.all(10.0),
            icon: Icon(Icons.phone),
            labelText: '请输入你的用户名)',
            helperText: '请输入注册的手机号',
          ),
          autofocus: false,
        ),
        TextField(
            controller: passController,
            keyboardType: TextInputType.number,
            decoration: InputDecoration(
              contentPadding: EdgeInsets.all(10.0),
              icon: Icon(Icons.lock),
              labelText: '请输入密码)',
            ),
            obscureText: true),
        RaisedButton(
          onPressed: _login,
          child: Text('登录'),
        ),
        ],
        ),
      ),
    );
  }

  void _login() {
    print({'手机号': phoneController.text, '密码': passController.text});
      phoneController.clear();
    }
  }

此外，Row包含Textfield时错误的解决办法