当我使用小部件Scrollbar向我的ListView添加滚动条时,这个断言会被抛出,尽管布局正常运行。完整的信息和相关代码如下:
══╡ EXCEPTION CAUGHT BY SCHEDULER LIBRARY ╞═
I/flutter ( 4453): The following assertion was thrown during a scheduler callback:
I/flutter ( 4453): 'package:flutter/src/material/scrollbar.dart': Failed assertion: line 111 pos 2
Exception caught by rendering library ═════════════════════════════════
RenderBox was not laid out: RenderFlex#0bf43 relayoutBoundary=up6 NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
'package:flutter/src/rendering/box.dart':
Failed assertion: line 1687 pos 12: 'hasSize'
The relevant er
当从.json执行文件时,我在flutter和dart中编程时出现此错误。有人知道如何修复它吗? ════════ Exception caught by image resource service ════════════════════════════
The following NoSuchMethodError was thrown resolving an image codec:
The getter 'length' was called on null.
Receiver: null
Tried calling: length
When the excep
所以,我想做的是,除了我的应用程序栏,我有标识和搜索选项,我想添加底部TabBar,用户可以选择电影或电视节目,而当他在其中一个,文本应该亮(不同的颜色)。但是,当我试图添加TabBar时,我得到了一个错误:
══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
The following assertion was thrown building MediaQuery(MediaQueryData(size: Size(411.4, 683.4)
我想显示一个文本(或其他类型的内容)和一个卡片列表。我只能显示Cards列表,但是如果我添加另一个类,它会抛出一个异常。 仅用于卡片列表的代码(它可以工作): class CardPageState extends State<CardPage> {
//DeckCard is a class which contains title, description, etc
final decks = <DeckCard>[];
CardPageState(data){
decks.addAll(data);
}
@override
我在一个管理页面上工作,我在一个特定的页面上有三个字段,在此之前,我在文本字段中显示错误消息时遇到了问题,但当我修复了这个错误并开始运行我的应用程序时,我遇到了一个新的error.can,有人请帮帮我吧。
下面是我的代码:
class _AddPromoState extends State<AddPromo> {
final databaseReference = Firestore.instance;
var priceReductionController = TextEditingController();
var perReductionController
当我在flutter web项目中添加一些像ListView这样的小部件时,我遇到了这个错误,这是我以前在使用安卓系统时从未遇到过的
Exception has occurred.
"Error: Assertion failed: file:///D:/Android/flutter/packages/flutter/lib/src/rendering/mouse_tracking.dart:312:12
!_debugDuringDeviceUpdate
is not true
at Object.throw_ [as throw] (http://localhos
我正在开发一个简单的ListView应用程序,它可以从互联网上填充,并使用提供者存储在数据库中。但是ListView没有被填充。它在条目获取器上变得无效。但在我改变了对消费者的看法之后。
现在我得到一个错误,在null上调用了getter项。
堆栈过流
══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
I/flutter (15505): The following NoSuchMethodError was thrown building
我试图创建一个ListView,但是当我导入list_form.dart类时,我会得到这个错误。也许我在布局上犯了一些错误,因为如果我试图在主文件中运行它,我就不会得到这个错误。
这是一个错误:
I/flutter (12956): ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
I/flutter (12956): The following assertion was thrown during performResize():
当我向我的SliverList添加一个新项目时,我有以下错误。这个嵌套在CustomScrollView中,它嵌套在一个LiquidPullToRefresh ()中,用新的项更新我的列表。列表已经很好地更新了,但是我仍然有这个错误。
有什么想法吗?
误差
flutter: ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
flutter: The following assertion was thrown during performLay