按钮|图片|进度条

TextButton(
            child: Text('TextButton'),
            style: ButtonStyle(
                textStyle:MaterialStateProperty.all(TextStyle(fontSize: 16)),
                foregroundColor: MaterialStateProperty.all(Colors.black),
                //backgroundColor:MaterialStateProperty.all(Colors.green)
              ),
            onPressed: () {//onPressed: null,禁用按钮
              BrnToast.show('单机',context);
            },
            onLongPress: () {
              BrnToast.show('长按',context);
            },
          ),
          ElevatedButton(
            child: Text('ElevatedButton'),
            style: ButtonStyle(
                textStyle:MaterialStateProperty.all(TextStyle(fontSize: 16)),
                foregroundColor: MaterialStateProperty.all(Colors.white),
                //backgroundColor:MaterialStateProperty.all(Colors.green)
            ),
            onPressed: () {//onPressed: null,禁用按钮
              BrnToast.show('单机',context);
            },
            onLongPress: () {
              BrnToast.show('长按',context);
            }
          ),
          OutlinedButton(
            child: Text('OutlinedButton按钮'),
            style: ButtonStyle(
              textStyle:MaterialStateProperty.all(TextStyle(fontSize: 16)),
              foregroundColor: MaterialStateProperty.all(Colors.black),
              //backgroundColor:MaterialStateProperty.all(Colors.green)
            side:MaterialStateProperty.all(BorderSide(width:1,color: Colors.green))
            ),
            onPressed: () {//onPressed: null,禁用按钮
              BrnToast.show('单机',context);
            },
            onLongPress: () {
              BrnToast.show('长按',context);
            },
          ),
          OutlinedButton.icon(
              icon: const Icon(Icons.keyboard_arrow_left),
            label: Text('图标按钮'),
            style: ButtonStyle(
                textStyle:MaterialStateProperty.all(TextStyle(fontSize: 16)),
                foregroundColor: MaterialStateProperty.all(Colors.black),
                //backgroundColor:MaterialStateProperty.all(Colors.green)
                side:MaterialStateProperty.all(BorderSide(width:1,color: Colors.green))
            ),
            onPressed: () {//onPressed: null,禁用按钮
              BrnToast.show('单机',context);
            },
            onLongPress: () {
              BrnToast.show('长按',context);
            },
          ),
          IconButton(icon: Icon(Icons.add),
            color: Colors.lightBlue,
            iconSize: 24,
            onPressed: () {//onPressed: null,禁用按钮
            BrnToast.show('单机',context);
          }
          )
//开关两种
bool _switchSelected=true; //维护单选开关状态
bool _checkboxSelected=true;//维护复选框状态
  Switch(
            value: _switchSelected,//当前状态
            onChanged:(value){
              //重新构建页面
              print(value);
              setState(() {
                _switchSelected=value;
              });
            },
          ),
          SwitchListTile(
            title:Text('是否开启'),
            activeColor: Colors.green,
            activeTrackColor: Colors.green,
            value: _switchSelected,//当前状态
            onChanged:(value){
              //重新构建页面
              print(value);
              setState(() {
                _switchSelected=value;
              });
            },
          ),
          Checkbox(
            value: _checkboxSelected,
            activeColor: Colors.red, //选中时的颜色
            onChanged:(value){
              print(value);
              setState(() {
                _checkboxSelected=value!;
              });
            } ,
          ),
          CheckboxListTile(
            title:Text('是否开启'),
            //controlAffinity: ListTileControlAffinity.leading,//勾选在前,默认在后面
            activeColor: Colors.green,
            subtitle: Text('描述'),
            secondary: Icon(Icons.person),
            value: _checkboxSelected,
            onChanged:(value){
              print(value);
              setState(() {
                _checkboxSelected=value!;
              });
            } ,
          ),            
          单选
var _radioGroupValue = '语文';//默认值
RadioListTile(
            title: Text('语文'),
            value: '语文',
            groupValue: _radioGroupValue,
            onChanged: (value) {
              setState(() {
                _radioGroupValue = value!;
              });
            },
          ),
          滑块
            RangeValues _rangeValues = RangeValues(0, 20);
double _sliderValue = 0;
RangeSlider(
            values: _rangeValues,
            labels: RangeLabels('${_rangeValues.start}','${_rangeValues.end}'),
            min: 0,
            max: 100,
            divisions: 100,
            onChanged: (v) {
              setState(() {
                _rangeValues = v;
              });
            },
          ),
          Slider(
            value: _sliderValue,
            label: '$_sliderValue',
            min: 0,
            max: 100,
            divisions: 100,
            onChanged: (v){
              setState(() {
                _sliderValue = v;
              });
            },
          )
线性和圆形进度条
LinearProgressIndicator(
            value: 0.3,//长度0-1之间
              backgroundColor:Colors.grey,//背景色
            valueColor: AlwaysStoppedAnimation<Color>(Colors.green),//进度色
          ),
          CircularProgressIndicator(
            value: 0.3,
            backgroundColor: Colors.grey,
            valueColor: AlwaysStoppedAnimation<Color>(Colors.green),
          )
图片图标,前面一定要有空格
assets:
  - assets/images/
Image.asset('assets/images/1.webp',width: 100,height: 200,fit:BoxFit.cover),
          Image.network("http://pic1.win4000.com/pic/c/cf/cdc983699c.jpg",width: 200,height: 200,fit:BoxFit.cover),//充满宽高
          Image.memory(base64Decode("")),//图片base64,需要import 'dart:convert';