flutter 每天一背，需要掌握

1.基本类怎么写的，init和dispose里面的内容都写在super.前面
2.json解析类怎么写的，基本类型，范类，列表
3.EventBus怎么用的，发送消息，监听，注销
4.弹窗怎么写的，两种方式，中间弹出来的showDialog，还有从屏幕下面弹起来的showModalBottomSheet
5. 列表怎么写,嵌套在滑动列表里面的列表,缺省图，滑动控制器，下拉刷新
6. switch case怎么写,switch(){},:;;
7. 创建一个空列表，可增加长度类型的List? currentMessageList = List.empty(growable: true);，根据创建时间来排序currentMessageList?.sort((a, b) => a.createTime!.compareTo(b.createTime!));
8. provider，填数据，刷新数据，获取数据，对象和列表两种方式
如果是对象：

//填数据
  DriftBottleSetting? driftBottleSetting;//这个是服务器返回的数据
  Provider.of<providers>(Global.appContext,listen:false).getDriftBottleSetting(driftBottleSetting!);
  
  //刷新数据
class providers extends ChangeNotifier{
    
  DriftBottleSetting? driftBottleSetting;
  get _driftBottleSetting =>driftBottleSetting;
  getDriftBottleSetting(DriftBottleSetting driftBottleSetting){
    
    driftBottleSetting=driftBottleSetting;
    notifyListeners();
    return driftBottleSetting;
  }
    clear() {
    
    _driftBottleSetting=null;//一般在登录的时候会调用一次清楚数据，通过：Provider.of<SlideMatchModel>(context, listen: false).clear();
    notifyListeners();
  }
}

//获取数据
DriftBottleSetting? driftBottleSetting;
driftBottleSetting=Provider.of<providers>(context,listen: false).driftBottleSetting;//在build里面写

}

如果是列表也是同样的操作

//刷新数据类
import 'package:flutter/foundation.dart';

import '../pages/driftBottleGame/data/reply_list.dart';

class BottleProvider with ChangeNotifier, DiagnosticableTreeMixin{
    
  List<DownList>? currentMessageList = List.empty(growable: true);

  addDownList(List<DownList>? downLists){
    
    if(downLists!.isNotEmpty) {
    
      currentMessageList?.addAll(downLists);
    }

    currentMessageList?.sort((a, b) => a.createTime!.compareTo(b.createTime!));
    notifyListeners();
  }

  clear(){
    
    currentMessageList?.clear();
    // notifyListeners();
  }
}

//在initState先清空数据
Provider.of<BottleProvider>(context,listen: false).clear();

//在网络请求处获取到数据后填充数据
Provider.of<BottleProvider>(context,listen: false).addDownList(currentMessageList);//currentMessageList就是获得的数据

//在build处使用数据
List<DownList>? currentMessageList = Provider.of<BottleProvider>(context,listen: true).currentMessageList;

9.时间戳转日期

  String getMessageTime() {
    
    String time = '';
    int timestamp = downList.createTime! * 1000;
    DateTime timeDate = DateTime.fromMillisecondsSinceEpoch(timestamp);
    DateTime now = DateTime.now();

    if (now.day == timeDate.day) {
    
      time =
          "${timeDate.hour.toString().padLeft(2, '0')}:${timeDate.minute.toString().padLeft(2, '0')}:${timeDate.second.toString().padLeft(2, '0')}";
    } else {
    
      time =
          "${timeDate.month.toString().padLeft(2, '0')}-${timeDate.day.toString().padLeft(2, '0')} ${timeDate.hour.toString().padLeft(2, '0')}:${timeDate.minute.toString().padLeft(2, '0')}:${timeDate.second.toString().padLeft(2, '0')}";
    }
    return time;
  }

10.列表的另外一个写法

Column(
          key: _containerKey,
          children:
              (currentMessageList == null || currentMessageList.length == 0)
                  ? [Container()]: replyList == null
                  ? [Container()]
                  : currentMessageList.map((e) => MsgContainer(replyList: replyList!,downList: e,)).toList(),
        )//意思就是将列表里面的数据进行排成列表，根据list里面的长度进行排成列表，数据就是e，MsgContainer是单个item的样式