本文介绍了在文本小部件中使用变量的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我正在尝试在Text Widget中使用一个变量,它表示无效的const值,因此,我需要使用const,但是我正在以动态方式使用Text Widget。有没有办法使用带有变量的文本?还是有另一个我可以使用的小部件?
我有这样的东西:
class PlaceCardStateextends StatelessWidget {
PlaceCardState(this._placeCard);
Place _placeCard;
@override
小部件构建(BuildContext上下文){
return ListTile(
开头:const Icon(Icons.album),
title:Text( _placeCard.title),
字幕:const Text('今晚来跳舞!'),
);
}
}
place.dart
class Place {
Place([this.title ='',this.description ='',this.image ='',this.value = 0.0]);
字符串标题;
字符串描述;
字符串图像;
双重价值;
}
我遇到了这个问题:
解决方案
更改此内容:
const ListTile(
开头:const Icon(Icons.album),
标题:Text(_placeCard.title),
副标题:const Text('Come今晚跳舞!'),
);
为此:
const ListTile(
开头:const Icon(Icons.album),
标题:const Text(_placeCard.title),
字幕:const Text('Come and dance今晚!'),
);
由于您的屏幕截图中的 ListTile
是常量那么所有属性也需要保持不变,因此在 Text(_placeCard.title),
I'm trying to use a variable in Text Widget, it says Invalid const value, so, I need to use a const, but I'm using Text Widget in a dynamic way. Is there a way to use a Text with variables? or is there another Widget that I could use?
I have something like this:
class PlaceCardState extends StatelessWidget {
PlaceCardState(this._placeCard);
Place _placeCard;
@override
Widget build(BuildContext context) {
return ListTile(
leading: const Icon(Icons.album),
title: Text(_placeCard.title),
subtitle: const Text('Come and dance tonight!'),
);
}
}
place.dart
class Place {
Place([this.title = '', this.description = '', this.image='', this.value=0.0]);
String title;
String description;
String image;
double value;
}
I get this issue:
解决方案
Change this:
const ListTile(
leading: const Icon(Icons.album),
title: Text(_placeCard.title),
subtitle: const Text('Come and dance tonight!'),
);
into this:
const ListTile(
leading: const Icon(Icons.album),
title: const Text(_placeCard.title),
subtitle: const Text('Come and dance tonight!'),
);
Since in your screenshot ListTile
is a constant then all the properties need to be constant also, therefore add const
before Text(_placeCard.title),
这篇关于在文本小部件中使用变量的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!