Flutter聊天室dart+flutter仿微信App界面flutter聊天实例

Flutter聊天室dart+flutter仿微信App界面flutter聊天实例

一、项目概述

flutter-chatroom是采用基于flutter+dart+chewie+image_picker+photo_view等技术跨端开发仿微信app界面聊天室项目。实现了消息发送/动态gif表情、弹窗、图片预览、红包/朋友圈/小视频号等功能。

二、技术框架

• 编码/技术：Vscode + 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：SimpleDialog/showModalBottomSheet/AlertDialog/SnackBar（flutter封装自定义）
• 本地存储：shared_preferences: ^0.5.7+1
• 字体图标：阿里iconfont字体图标库

由于flutter基于dart语言，需要先安装Dart Sdk / Flutter Sdk，如何搭建开发环境，不作过多介绍，可以去官网查阅文档资料

https://flutter.cn/

https://flutterchina.club/

https://pub.flutter-io.cn/

https://www.dartcn.com/

如果使用vscode编辑器开发，可先安装Dart 、Flutter 、Flutter widget snippets等扩展插件

◆ flutter沉浸式状态栏/底部tabbar导航

在flutter中如何实现沉浸式透明状态栏(去掉状态栏黑色半透明背景)，去掉右上角banner提示，可以去看这篇文章

https://www.cnblogs.com/xiaoyan2017/p/12784076.html

 

◆ flutter中使用字体图标 (阿里iconfont图标)

• 方法1： 使用系统图标组件： Icon(Icons.search) 
• 方法2： 使用IconData方式： Icon(IconData(0xe60e, fontFamily: 'iconfont'), size: 24.0)

方法2 需要先下载阿里图标库字体文件，然后在pubspec.yaml中申明字体

 

通过IconData调用简单封装： GStyle.iconfont(0xe635, color: Colors.red, size: 14.0) 

class GStyle { // __ 自定义图标 static iconfont(int codePoint, {double size = 16.0, Color color}) {  return Icon(   IconData(codePoint, fontFamily: 'iconfont', matchTextDirection: true),   size: size,   color: color,  ); }}

 

◆ flutter中红点/圆点提示

在flutter中没有上图这个红点提示组件，如是简单封装个badge组件

 GStyle.badge(0, isdot: true) 

 GStyle.badge(13, color: Colors.green, height: 12.0, width: 12.0) 

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主入口页面main.dart

/** * @tpl Flutter入口页面 | Q：282310962 */import 'package:flutter/material.dart';// 引入公共样式import 'styles/common.dart';// 引入底部Tabbar页面导航import 'components/tabbar.dart';// 引入地址路由import 'router/routes.dart';void main() => runApp(MyApp());class MyApp extends StatelessWidget { @override Widget build(BuildContext context) { return MaterialApp(  title: 'Flutter App',  debugShowCheckedModeBanner: false,  theme: ThemeData(  primaryColor: GStyle.appbarColor,  ),  home: TabBarPage(),  onGenerateRoute: onGenerateRoute, ); }}

 

◆ flutter自定义弹窗实现

长按获取点坐标，通过Positioned组件left top属性实现定位，width控制弹窗宽度

InkWell( splashColor: Colors.grey[200], child: Container(...), onTapDown: (TapDownDetails details) {  _globalPositionX = details.globalPosition.dx;  _globalPositionY = details.globalPosition.dy; }, onLongPress: () {  _showPopupMenu(context); },),

// 长按弹窗double _globalPositionX = 0.0; //长按位置的横坐标double _globalPositionY = 0.0; //长按位置的纵坐标void _showPopupMenu(BuildContext context) { // 确定点击位置在左侧还是右侧 bool isLeft = _globalPositionX > MediaQuery.of(context).size.width/2 ? false : true; // 确定点击位置在上半屏幕还是下半屏幕 bool isTop = _globalPositionY > MediaQuery.of(context).size.height/2 ? false : true; showDialog(  context: context,  builder: (context) {  return Stack(   children: <Widget>[   Positioned(    top: isTop ? _globalPositionY : _globalPositionY - 200.0,    left: isLeft ? _globalPositionX : _globalPositionX - 120.0,    width: 120.0,    child: Material(    ...    ),   )   ],  );  } );}

flutter中可否去掉弹窗宽高限制？通过SizedBox组件设置宽度，外层包裹布局无限制容器UnconstrainedBox组件

void _showCardPopup(BuildContext context) { showDialog(  context: context,  builder: (context) {  return UnconstrainedBox(   constrainedAxis: Axis.vertical,   child: SizedBox(   width: 260,   child: AlertDialog(    content: Container(    ...    ),    elevation: 0,    contentPadding: EdgeInsets.symmetric(horizontal: 10.0, vertical: 20.0),   ),   ),  );  } );}

 

◆ flutter/dart登录、注册表单验证

TextField文本框，右侧清空文本框按钮通过Visibility组件控制

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; }); },)

// SnackBar提示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), ));}

本地存储使用的是 shared_preferences

https://pub.flutter-io.cn/packages/shared_preferences

void handleSubmit() async { if(formObj['tel'] == '') {  _snackbar('手机号不能为空'); }else if(!Util.checkTel(formObj['tel'])) {  _snackbar('手机号格式有误'); }else if(formObj['pwd'] == '') {  _snackbar('密码不能为空'); }else {  // ...接口数据  // 设置存储信息  final prefs = await SharedPreferences.getInstance();  prefs.setBool('hasLogin', true);  prefs.setInt('user', int.parse(formObj['tel']));  prefs.setString('token', Util.setToken());  _snackbar('恭喜你，登录成功', color: Colors.greenAccent[400]);  Timer(Duration(seconds: 2), (){  Navigator.pushNamedAndRemoveUntil(context, '/tabbarpage', (route) => route == null);  }); }}

flutter中获取验证码60s倒计时，使用Timer.periodic实现

// 60s倒计时void handleVcode() { if(formObj['tel'] == '') {  _snackbar('手机号不能为空'); }else if(!Util.checkTel(formObj['tel'])) {  _snackbar('手机号格式有误'); }else {  _countDown(); }}_countDown() { if(_validTimer != null) return;  _validTimer = Timer.periodic(Duration(seconds: 1), (t) {  setState(() {  if(formObj['time'] > 0) {   formObj['disabled'] = true;   formObj['vcodeText'] = '获取验证码(${formObj["time"]--})';  }else {   formObj['time'] = 60;   formObj['vcodeText'] = '获取验证码';   formObj['disabled'] = false;     _validTimer.cancel();   _validTimer = null;  }  }); });}

 

◆ flutter聊天页面解析

flutter中如何实现TextField换行文本框(类似微信聊天编辑框)，设置  maxLines 属性就能实现多行文本。

不过设置maxLines，文本框有一定高度，这时只需设置maxLines: null及keyboardType并在外层加个容器限制最小高度即可。

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();}, ),),

另外通过文本框focusNode属性可以实现隐藏键盘

FocusNode _focusNode = FocusNode();...void clickMsgPanel() { // 隐藏键盘 _focusNode.unfocus(); setState(() { showFootToolbar = false; });}

flutter中如何实现滚动聊天信息至底部？

通过ListView里controller的获取最大滚动距离，并通过jumpTo方法滚动。

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));}

ok，基于flutter+dart跨平台开发仿微信聊天实例项目就分享到这里，希望大家能喜欢！😁😁

最后附上基于electron+vue桌面端IM实例

https://www.cnblogs.com/xiaoyan2017/p/12169391.html