flutter聊天app应用实例|flutter聊天界面
FlutterChat聊天室项目是基于flutter+dart+video_player+photo_view+image_picker等技术实现的跨平台聊天实例。项目整体界面仿制微信聊天app，实现了消息/表情发送、图片预览、Popwin长按弹窗、视频/红包/朋友圈功能。
技术栈
使用技术：Flutter 1.12.13/Dart 2.7.0
视频组件：chewie: ^0.9.7
图片/拍照：image_picker: ^0.6.6+1
图片预览组件：photo_view: ^0.9.2
弹窗组件：showModalBottomSheet/AlertDialog/SnackBar
本地存储：shared_preferences: ^0.5.7+1
字体图标：阿里iconfont字体图标库
flutter登录|注册表单验证
flutter提供了两个文本框组件：TextField 和 TextFormField
本文是使用TextField实现，并在文本框后添加清空文本框/密码查看图标
TextField(
keyboardType: TextInputType.phone,
controller: TextEditingController.fromValue(TextEditingValue(
text: formObj['tel'],
selection: new TextSelection.fromPosition(TextPosition(affinity: TextAffinity.downstream, offset: formObj['tel'].length))
)),
decoration: InputDecoration(
hintText: "请输入手机号",
isDense: true,
hintStyle: TextStyle(fontSize: 14.0),
suffixIcon: Visibility(
visible: formObj['tel'].isNotEmpty,
child: InkWell(
child: GStyle.iconfont(0xe69f, color: Colors.grey, size: 14.0), onTap: () {
setState(() { formObj['tel'] = ''; });
}
),
),
border: OutlineInputBorder(borderSide: BorderSide.none)
),
onChanged: (val) {
setState(() { formObj['tel'] = val; });
},
)
TextField(
decoration: InputDecoration(
hintText: "请输入密码",
isDense: true,
hintStyle: TextStyle(fontSize: 14.0),
suffixIcon: InkWell(
child: Icon(formObj['isObscureText'] ? Icons.visibility_off : Icons.visibility, color: Colors.grey, size: 14.0),
onTap: () {
setState(() {
formObj['isObscureText'] = !formObj['isObscureText'];
});
},
),
border: OutlineInputBorder(borderSide: BorderSide.none)
),
obscureText: formObj['isObscureText'],
onChanged: (val) {
setState(() { formObj['pwd'] = val; });
},
)
通过flutter提供的SnackBar来提示消息
final _scaffoldkey = new GlobalKey<ScaffoldState>();
void _snackbar(String title, {Color color}) {
_scaffoldkey.currentState.showSnackBar(SnackBar(
backgroundColor: color ?? Colors.redAccent,
content: Text(title),
duration: Duration(seconds: 1),
));
}
flutter桌面app启动图标右上角圆点|未读消息小红点
如上图：在flutter中没有圆点提示组件，需要自己封装实现；
class GStyle {
// 消息红点
static badge(int count, {Color color = Colors.red, bool isdot = false, double height = 18.0, double width = 18.0}) {
final _num = count > 99 ? '···' : count;
return Container(
alignment: Alignment.center, height: !isdot ? height : height/2, width: !isdot ? width : width/2,
decoration: BoxDecoration(color: color, borderRadius: BorderRadius.circular(100.0)),
child: !isdot ? Text('$_num', style: TextStyle(color: Colors.white, fontSize: 12.0)) : null
);
}
}
flutter聊天页面模块功能
flutter中TextField文本框提供的maxLines属性可实现多行/换行文本，不过默认会有个高度，可在外层加个容器限制最小高度，然后设置 maxLines: null、 keyboardType: TextInputType.multiline
Container(
margin: GStyle.margin(10.0),
decoration: BoxDecoration(color: Colors.white, borderRadius: BorderRadius.circular(3.0)),
constraints: BoxConstraints(minHeight: 30.0, maxHeight: 150.0),
child: TextField(
maxLines: null,
keyboardType: TextInputType.multiline,
decoration: InputDecoration(
hintStyle: TextStyle(fontSize: 14.0),
isDense: true,
contentPadding: EdgeInsets.all(5.0),
border: OutlineInputBorder(borderSide: BorderSide.none)
),
controller: _textEditingController,
focusNode: _focusNode,
onChanged: (val) {
setState(() {
editorLastCursor = _textEditingController.selection.baseOffset;
});
},
onTap: () {handleEditorTaped();},
),
),
通过ListView里controller属性提供的jumpTo方法及_msgController.position.maxScrollExtent
ScrollController _msgController = new ScrollController();
ListView(
controller: _msgController,
padding: EdgeInsets.all(10.0),
children: renderMsgTpl(),
)
// 滚动消息至聊天底部
void scrollMsgBottom() {
timer = Timer(Duration(milliseconds: 100), () => _msgController.jumpTo(_msgController.position.maxScrollExtent));
}
okey，基于flutter+dart开发聊天实例就介绍到这里，后续会分享更多实战案例！！💪💪
作者：xiaoyan2019
https://www.bilibili.com/read/cv5983396
出处： bilibili
