Flutter Chip的使用

Posted 2022-08-31 一叶飘舟

1. 基本介绍

Chip、ActionChip、ChoiceChip、FilterChip 是一个常见的标签控件，会内敛布局，并且有一些常用的点击功能。

2. 示例代码

代码下载地址。如果对你有帮助的话记得给个关注，代码会根据我的 Flutter 专题不断更新。

3. 属性介绍

Chip 属性	介绍
avatar	左侧图标组件
label	@required 文本 Widget
labelStyle	文本样式，TextStyle
labelPadding	文本外边距 Padding
deleteIcon	右侧删除按钮 Widget
onDeleted	删除按钮点击事件
deleteIconColor	删除按钮颜色
deleteButtonTooltipMessage	长按删除按钮的提示语
shape	形状，ShapeBorder
clipBehavior	裁剪方式，默认为 Clip.none
focusNode	焦点控制，Flutter 组件之 FocusNode 详解
autofocus	自动聚焦，默认为 false
backgroundColor	背景色
padding	内边距 Padding
visualDensity	紧凑程度，VisualDensity
materialTapTargetSize	内边距，默认最小点击区域为 48 * 48，MaterialTapTargetSize.shrinkWrap 为组件实际大小
elevation	阴影高度，默认为 0
shadowColor	阴影颜色

CircleAvatar 属性	介绍
child	子控件 Widget
backgroundColor	背景色
backgroundImage	背景图
onBackgroundImageError	背景图加载失败回调
foregroundColor	text 颜色
radius	半径 (和 maxRadius 以及 minRadius 不能同时存在)
minRadius	最小半径 (和 radius 不能同时存在)
maxRadius	最大半径 (和 radius 不能同时存在)

4. Chip 详解

import 'package:flutter/material.dart';

class FMChipVC extends StatefulWidget 
  @override
  FMChipState createState() => FMChipState();


class FMChipState extends State <FMChipVC>
  @override
  Widget build(BuildContext context) 
    // TODO: implement build
    return Scaffold(
      appBar: AppBar(title: Text("Chip"),),
      body: _listView(),
    );
  

  ListView _listView()
    return ListView(
      children: [
        _chipForSimpleText(),
        _chipForSimple(),
        _chipForNormal(),
        _chip(),
      ],
    );
  

  CircleAvatar _circleAvatar()
    return CircleAvatar(
      child: Container(
        height: 30,
        color: Colors.red,
        alignment: Alignment.center,
        child: Text("Avatar child text"),
      ), // avatar 子控件
      backgroundColor: Colors.red, // avatar 背景色
      foregroundColor: Colors.white, // avatar 中 text 颜色
      // avatra 背景图
      backgroundImage: NetworkImage("http://tiebapic.baidu.com/forum/w%3D580/sign=a96ca741eafaaf5184e381b7bc5594ed/7ea6a61ea8d3fd1f2643ad5d274e251f95ca5f38.jpg"),
      // 背景图加载失败回调
      onBackgroundImageError: (error, trace)
        print("onBackgroundImageError");
      ,
      // radius: 200, // avatar 半径 (和 maxRadius 以及 minRadius 不能同时存在)
      maxRadius: 100, // avatar 最小半径 (和 radius 不能同时存在)
      minRadius: 80, // avatar 最大半径 (和 radius 不能同时存在)
    );
  

  Chip _chipForSimpleText()
    return Chip(
        label: Text("Simple Text Chip")
    );
  

  Chip _chipForSimple()
    return Chip(
      label: Text("Simple Chip"),
      avatar: CircleAvatar(backgroundColor: Colors.red,),
    );
  

  Chip _chipForNormal()
    return Chip(
      label: Text("Normal Chip"),
      avatar: CircleAvatar(backgroundColor: Colors.red,),
      deleteIcon: Icon(Icons.ac_unit),
      onDeleted: (),
    );
  
  
  Chip _chip()
    return Chip(
      avatar: _circleAvatar(), // 左侧图标组件
      label: Text("text"), // 文本 Widget
      labelStyle: TextStyle(color: Colors.red, fontSize: 30), // 文本样式，TextStyle
      labelPadding: EdgeInsets.fromLTRB(15, 50, 0, 50), // 文本外边距 Padding

      deleteIcon: Icon(Icons.ac_unit), // 右侧删除按钮 Widget
      deleteButtonTooltipMessage: "deleteButtonTooltipMessage", // 长按删除按钮的提示语
      deleteIconColor: Colors.red, // 删除按钮颜色
      // 删除按钮点击事件
      onDeleted: ()
        print("onDeleted");
      ,
      // Chip 形状
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(10),
        side: BorderSide(
          width: 2,
          color: Colors.red,
        ),
      ),

      // padding: EdgeInsets.zero,
    );
  

5. ActionChip 详解

相比 Chip，ActionChip 增加了 onPressed 的点击事件，同时 ActionChip 移除了 deleteIcon 等相关属性。

  ListView _listView()
    return ListView(
      children: [
        _chipForSimpleText(),
        _chipForSimple(),
        _chipForNormal(),
        _chip(),
        Padding(padding: EdgeInsets.all(10)),
        _actionChip(),
      ],
    );
  

  ActionChip _actionChip()
    return ActionChip(
      avatar: _circleAvatar(),
      onPressed: ()
        print("ActionChip onPressed");
      ,
      label: Text("ActionChip"), // 文本 Widget
      labelStyle: TextStyle(color: Colors.red, fontSize: 30), // 文本样式，TextStyle
      labelPadding: EdgeInsets.fromLTRB(15, 50, 0, 50), // 文本外边距 Padding

      // Chip 形状
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(10),
        side: BorderSide(
          width: 2,
          color: Colors.red,
        ),
      ),
    );
  

6. ChoiceChip 详解

  ListView _listView()
    return ListView(
      children: [
        _chipForSimpleText(),
        _chipForSimple(),
        _chipForNormal(),
        _chip(),
        Padding(padding: EdgeInsets.all(10)),
        _actionChip(),
        Padding(padding: EdgeInsets.all(10)),
        _choiceChip(),
      ],
    );
  

  bool _choiceChipSelected = false;

  ChoiceChip _choiceChip()
    return ChoiceChip(
      avatar: _circleAvatar(), // 左侧图标组件
      label: Text("ChoiceChip"), // 文本 Widget
      labelStyle: TextStyle(color: Colors.red, fontSize: 30), // 文本样式，TextStyle
      labelPadding: EdgeInsets.fromLTRB(15, 50, 0, 50), // 文本外边距 Padding

      selected: _choiceChipSelected, // 是否选中
      selectedColor: Colors.yellow, // 选中背景色
      // 选中点击事件
      onSelected: (value)
        print("ChoiceChip onSelected");
        _choiceChipSelected = value;
        setState(() 

        );
      ,

      // Chip 形状
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(10),
        side: BorderSide(
          width: 2,
          color: Colors.red,
        ),
      ),
    );
  

7. FilterChip 详解

  ListView _listView()
    return ListView(
      children: [
        _chipForSimpleText(),
        _chipForSimple(),
        _chipForNormal(),
        _chip(),
        Padding(padding: EdgeInsets.all(10)),
        _actionChip(),
        Padding(padding: EdgeInsets.all(10)),
        _choiceChip(),
        Padding(padding: EdgeInsets.all(10)),
        _filterChip(),
      ],
    );
  

  bool _filterChipSeleted = false;

  FilterChip _filterChip()
    return FilterChip(
      avatar: _circleAvatar(), // 左侧图标组件
      label: Text("text"), // 文本 Widget
      labelStyle: TextStyle(color: Colors.red, fontSize: 30), // 文本样式，TextStyle
      labelPadding: EdgeInsets.fromLTRB(15, 50, 0, 50), // 文本外边距 Padding

      selected: _filterChipSeleted, // 是否选中
      selectedColor: Colors.white, // 选中背景色
      // 点击回调
      onSelected: (value)
        _filterChipSeleted = value;
        setState(() 

        );
      ,

      showCheckmark: true, // 是否显示勾选框
      checkmarkColor: Colors.yellow, // 勾选框颜色

      // Chip 形状
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(10),
        side: BorderSide(
          width: 2,
          color: Colors.red,
        ),
      ),
    );
  

8. 技术小结

Chip 其实并不难，就是属性较多，多加练习理解各个属性对应样式即可。 

---

扩展效果

一、效果

二、构造函数解析：

const Chip(
    Key key,
    this.avatar,//左侧的图标
    @required this.label,//这个是必填的参数，控件上显示的文本
    this.labelStyle,
    this.labelPadding,
    this.deleteIcon,//右侧的删除图标
    this.onDeleted,//删除图标的点击事件，如果不写该方法的话，deleteIcon显示不出来
    this.deleteIconColor,
    this.deleteButtonTooltipMessage,//点击删除图标后弹出的文本，类似于tooltip的效果
    this.shape,
    this.clipBehavior = Clip.none,//这个不晓得是啥
    this.backgroundColor,
    this.padding,
    this.materialTapTargetSize,//这个具体也不晓得怎么描述，它的两个值，一个为padded，一个为shrinkWrap，前者自带margin，后者好像没有margin，紧贴附近的控件
    this.elevation,//阴影深度
    this.shadowColor,//阴影颜色
  )

三、例子

import 'package:flutter/material.dart';
import 'package:the_first_one/utils/PageUtil.dart';
import 'InputChipDemo.dart';
import 'FilterChipDemo.dart';
import 'package:fluttertoast/fluttertoast.dart';

class ChipPage extends StatefulWidget 
  @override
  _ChipPageState createState() => _ChipPageState();


class _ChipPageState extends State<ChipPage> 
  int _valueChoice = 0;

  Widget _buildChoiceItem(int index) 
    return ChoiceChip(
      label: Text("ChoiceChip $index"),
      selectedColor: Colors.orange, //选中的颜色
      disabledColor: Colors.orange[100], //没选中的颜色
      onSelected: (bool selected) 
        setState(() 
          _valueChoice = selected ? index : null;
        );
      ,
      selected: _valueChoice == index,
      labelStyle: TextStyle(color: Colors.black54),
    );
  

  @override
  Widget build(BuildContext context) 
    return Scaffold(
      appBar: AppBar(
        title: Text("ChipDemo"),
      ),
      body: Center(
        child: SingleChildScrollView(
          child: Column(
            children: <Widget>[
              SizedBox(height: 10.0),
              Text("一、初步认识"),
              Divider(),
              Chip(
                label: Text("普通的chip"),
                labelStyle: TextStyle(color: Colors.black54),
                backgroundColor: Colors.orange,
              ),
              Chip(
                avatar: Icon(
                  Icons.arrow_forward,
                  color: Colors.black54,
                ),
                label: Text("带avatar的chip"),
                labelStyle: TextStyle(color: Colors.black54),
                backgroundColor: Colors.orange,
              ),
              Chip(
                avatar: CircleAvatar(
                  backgroundImage:
                      AssetImage('assets/images/illustration_1.jpg'),
                  radius: 18.0,
                ),
                label: Text("带avatar的chip"),
                labelStyle: TextStyle(color: Colors.black54),
                backgroundColor: Colors.orange,
              ),
              Chip(
                avatar: CircleAvatar(
                  backgroundImage:
                      AssetImage('assets/images/illustration_1.jpg'),
                  radius: 30.0,
                ),
                padding: EdgeInsets.all(0.0),
                label: Text("padding为0,labelPadding不为0的chip"),
                labelPadding: EdgeInsets.all(15.0),
                labelStyle: TextStyle(
                  color: Colors.black54,
                  fontSize: 10.0,
                  fontWeight: FontWeight.bold,
                ),
                backgroundColor: Colors.orange,
              ),
              Chip(
                label: Text("带deleteIcon的chip"),
                deleteIcon: Icon(Icons.close),
                deleteIconColor: Colors.black54,
                onDeleted: () 
                  print("点击了删除噢");
                ,
                deleteButtonTooltipMessage: "弹出提示",
                labelStyle: TextStyle(color: Colors.black54),
                backgroundColor: Colors.orange,
              ),
              Chip(
                label: Text("圆角矩形的chip"),
                deleteIcon: Icon(Icons.close),
                deleteIconColor: Colors.black54,
                onDeleted: () 
                  print("点击了删除噢");
                ,
                deleteButtonTooltipMessage: "弹出提示",
                shape: RoundedRectangleBorder(
                  borderRadius: BorderRadius.circular(2.0),
                ),
                labelStyle: TextStyle(color: Colors.black54),
                backgroundColor: Colors.orange,
              ),
              Chip(
                label: Text("尺寸最小的chip"),
                materialTapTargetSize: MaterialTapTargetSize.shrinkWrap,
                labelStyle: TextStyle(color: Colors.black54),
                backgroundColor: Colors.orange,
              ),
              Chip(
                label: Text("带阴影的chip"),
                shadowColor: Colors.grey,
                elevation: 10.0,
                labelStyle: TextStyle(color: Colors.black54),
                backgroundColor: Colors.orange,
              ),
              Divider(),
              Text("二、例子"),
              ActionChip(
                //自带一个onPress事件，有点击效果
                label: Text("ActionChip"),
                backgroundColor: Colors.orange,
                onPressed: () 
                  Fluttertoast.showToast(msg: "ActionChip");
                ,
              ),
              Wrap(
                spacing: 5.0, //主轴间距
                runSpacing: 8.0, //副轴间距
                children: List<Widget>.generate(2, (int index) 
                  return _buildChoiceItem(index);
                ),
              ),
              RaisedButton(
                  child: Text(
                    "FilterChipDemo",
                    style: TextStyle(color: Colors.black54),
                  ),
                  color: Colors.orange,
                  onPressed: () 
                    PageUtil().pushTo(context, FilterChipDemo());
                  ),
              RaisedButton(
                  child: Text(
                    "InputChipDemo",
                    style: TextStyle(color: Colors.black54),
                  ),
                  color: Colors.orange,
                  onPressed: () 
                    PageUtil().pushTo(context, InputChipDemo());
                  ),
              SizedBox(height: 10.0),
            ],
          ),
        ),
      ),
    );
  

四、其他

关于chip也可以看看以下扩展类，以下排列顺序按照功能的升序排列

1. ActionChip //比普通的chip多一个onPressed事件
2. ChoiceChip //允许从一组选项中进行单一选择
3. FilterChip //自带的比ChoiceChip多一个选中的勾勾的效果

import 'package:flutter/material.dart';

class FilterChipDemo extends StatefulWidget 
  @override
  _FilterChipDemoState createState() => _FilterChipDemoState();


class ActorFilterEntry 
  const ActorFilterEntry(this.name, this.initials);

  final String name;
  final String initials;


class _FilterChipDemoState extends State<FilterChipDemo> 
  final List<ActorFilterEntry> _cast = <ActorFilterEntry>[
    const ActorFilterEntry('Aaron Burr', 'AB'),
    const ActorFilterEntry('Alexander Hamilton', 'AH'),
    const ActorFilterEntry('Eliza Hamilton', 'EH'),
    const ActorFilterEntry('James Madison', 'JM'),
  ];
  List<String> _filters = <String>[];

  Iterable<Widget> get actorWidgets sync* 
    for (ActorFilterEntry actor in _cast) 
      yield Padding(
        padding: const EdgeInsets.all(4.0),
        child: FilterChip(
          avatar: CircleAvatar(child: Text(actor.initials)),
          label: Text(actor.name),
          selected: _filters.contains(actor.name),
          onSelected: (bool value) 
            setState(() 
              if (value) 
                _filters.add(actor.name);
               else 
                _filters.removeWhere((String name) 
                  return name == actor.name;
                );
              
            );
          ,
        ),
      );
    
  

  @override
  Widget build(BuildContext context) 
    return Scaffold(
      appBar: AppBar(
        title: Text("FilterChipDemo"),
      ),
      body: Column(
        children: <Widget>[
          Wrap(
            children: actorWidgets.toList(),
          ),
          Text('Look for: $_filters.join(', ')'),
        ],
      ),
    );
  

1. InputChip //比FilterChip多一个onPressed和onDeleted

import 'package:flutter/material.dart';

class InputChipDemo extends StatefulWidget 
  @override
  _InputChipDemoState createState() => _InputChipDemoState();


class _InputChipDemoState extends State<InputChipDemo> 
  List<String> list = [
    "摇滚",
    "音乐",
    "机车党",
    "android工程师",
    "全栈",
    "Python",
    "UI设计师",
    "测试小姐姐",
    "后台单身狗",
    "产品老大",
    "路边摊",
    "火锅 串串 麻辣烫",
    "篮球",
    "摄影",
    "户外",
    "客服",
    "超级自恋的小哥哥",
    "直播",
    "不忘初心 继续前行",
    "记性不好",
    "花容月貌",
    "榴莲控",
    "一定要穿美美的衣服"
  ];

  List<String> _filters = <String>[];

  Widget _buildItem(int index) 
    String content = list[index];
    return InputChip(
      avatar: CircleAvatar(
        backgroundImage: AssetImage('assets/images/illustration_1.jpg'),
        radius: 12.0,
      ),
      label: Text(
        content,
        style: TextStyle(fontSize: 12.0),
      ),
      shadowColor: Colors.grey,
      deleteIcon: Icon(
        Icons.close,
        color: Colors.black54,
        size: 14.0,
      ),
      onDeleted: () 
        setState(() 
          list.removeAt(index);
        );
      ,
      onSelected: (bool selected) 
        setState(() 
          if (selected) 
            _filters.add(list[index]);
           else 
            _filters.removeWhere((String name) 
              return name == list[index];
            );
          
        );
      ,
      selectedColor: Colors.orange,
      disabledColor: Colors.grey,
      selected: _filters.contains(list[index]),
      materialTapTargetSize: MaterialTapTargetSize.shrinkWrap,
      labelStyle: TextStyle(color: Colors.black54),
    );
  

  @override
  Widget build(BuildContext context) 
    return Scaffold(
      appBar: AppBar(
        title: Text("InputChipDemo"),
      ),
      body: Container(
        padding: EdgeInsets.all(10.0),
        child: Wrap(
          spacing: 5.0,
          //主轴间距
          runSpacing: 8.0,
          //副轴间距
          alignment: WrapAlignment.end,
          //主轴上的对齐方式
          crossAxisAlignment: WrapCrossAlignment.center,
          //副轴上的对齐方式
          children: List<Widget>.generate(
            list.length,
            (int index) 
              return _buildItem(index);
            ,
          ).toList(),
        ),
      ),
    );
  

1. RawChip //原始chip，通常仅在您想要创建自己的定制芯片类型时使用

五、补充

更多的应用场景，请点击我