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dart - onTap : only static members can be accessed in initializers error

帮助,当我在GestureDetector小部件或InkWell小部件的onTap属性中调用myMethod时,我得到一个onlystaticmemberscanbeaccessedininitializers错误staticStringseat1Source='images/carSeatBlack.png';_stater(){setState((){if(seat1Source=='images/carSeatBlack.png'){seat1Source='images/carSeatGreen.png';}else{seat1Source='images/carSeatBla

dart - onTap : only static members can be accessed in initializers error

帮助,当我在GestureDetector小部件或InkWell小部件的onTap属性中调用myMethod时,我得到一个onlystaticmemberscanbeaccessedininitializers错误staticStringseat1Source='images/carSeatBlack.png';_stater(){setState((){if(seat1Source=='images/carSeatBlack.png'){seat1Source='images/carSeatGreen.png';}else{seat1Source='images/carSeatBla

class - 错误 "Can' t access this in a field initializer 是什么意思”?

我想在flutter中创建一个显示警告框的类,它可以将标题和内容作为输入来显示错误框。但是当我使用它来访问AlertDialog()中同一类的变量时,调试控制台说“无法在字段初始值设定项中访问它”。import'package:flutter/material.dart';voidmain()=>runApp(MaterialApp(home:Alert("SayHy","Hy"),));classAlertextendsStatelessWidget{finalStringtitlea;finalStringcontexta;Alert(this.titlea,this.contex

class - 错误 "Can' t access this in a field initializer 是什么意思”?

我想在flutter中创建一个显示警告框的类,它可以将标题和内容作为输入来显示错误框。但是当我使用它来访问AlertDialog()中同一类的变量时,调试控制台说“无法在字段初始值设定项中访问它”。import'package:flutter/material.dart';voidmain()=>runApp(MaterialApp(home:Alert("SayHy","Hy"),));classAlertextendsStatelessWidget{finalStringtitlea;finalStringcontexta;Alert(this.titlea,this.contex

flutter : How can i get collection from document with cloud_firestore?

我可以从集合中获取所有文档,但不知道如何从每个文档中获取集合。我的数据库结构就像集合->文档->集合(带字段)->文档->字段。使用blow代码,只有我可以获得第一个文档的字段信息,而不是集合。我如何从每个第一个文档访问第二个集合。import'dart:async';import'package:flutter/material.dart';import'package:flutter/services.dart';import'package:google_maps_flutter/google_maps_flutter.dart';import'package:cloud_fir

flutter : How can i get collection from document with cloud_firestore?

我可以从集合中获取所有文档,但不知道如何从每个文档中获取集合。我的数据库结构就像集合->文档->集合(带字段)->文档->字段。使用blow代码,只有我可以获得第一个文档的字段信息,而不是集合。我如何从每个第一个文档访问第二个集合。import'dart:async';import'package:flutter/material.dart';import'package:flutter/services.dart';import'package:google_maps_flutter/google_maps_flutter.dart';import'package:cloud_fir

flutter 卡 : How can i create a custom card widget in flutter

我正在尝试在flutter中创建一个如下所示的自定义卡片:我怎样才能在flutter中实现这一点?这是我想要实现的: 最佳答案 您可以使用ClipPath自定义剪辑您的小部件ClipPath(clipper:_CustomClipper(),child:Container(width:200.0,height:100.0,color:Colors.grey,),)(以灰色容器为例)constdouble_topPadding=20.0;constdouble_arcRadius=8.0;class_CustomClipperexte

flutter 卡 : How can i create a custom card widget in flutter

我正在尝试在flutter中创建一个如下所示的自定义卡片:我怎样才能在flutter中实现这一点?这是我想要实现的: 最佳答案 您可以使用ClipPath自定义剪辑您的小部件ClipPath(clipper:_CustomClipper(),child:Container(width:200.0,height:100.0,color:Colors.grey,),)(以灰色容器为例)constdouble_topPadding=20.0;constdouble_arcRadius=8.0;class_CustomClipperexte

flutter : TextEditingController Only Static member can be accessed in initializer error

我正在将数据从listmosque.dart传递到update_screen.dart以更新数据。一切正常,但我想设置textedittingcontroller的默认值。TextEditingController_txtnrp=TextEditingController(text:"${widget.nrpUpdate}");我收到消息Onlystaticmemberscanbeaccessedininitializers.in${widget.nrpUpdate}如何解决这个问题?这是我的update_screen.dartimport'package:flutter/materi

flutter : TextEditingController Only Static member can be accessed in initializer error

我正在将数据从listmosque.dart传递到update_screen.dart以更新数据。一切正常,但我想设置textedittingcontroller的默认值。TextEditingController_txtnrp=TextEditingController(text:"${widget.nrpUpdate}");我收到消息Onlystaticmemberscanbeaccessedininitializers.in${widget.nrpUpdate}如何解决这个问题?这是我的update_screen.dartimport'package:flutter/materi