flutter的appBar使用自己写好的方法出现了 ‘HomeHeade‘ is not a subtype of type ‘PreferredSizeWi 解决办法
作者:互联网
本来想将appBar组件里面的内容 写在其他地方。但是写在其他地方报错
HomeHeade’ is not a subtype of type 'PreferredSizeWidget
HomeHeade代码:
class HomeHeade extends StatelessWidget {
@override
Widget build(BuildContext context) {
return AppBar(
centerTitle:true,
title:Text('生存日记',style: TextStyle(color: Color(0xFF02020D))),
flexibleSpace: Container(
decoration: BoxDecoration(
gradient: LinearGradient(colors: [
Color(0xFFFAD956),
Colors.white,
], begin: Alignment.topCenter, end: Alignment.bottomCenter),
),
),
);
}
}`
支架需要将实现 PreferredSizeWidget的类作为appbar`
implements PreferredSizeWidget
更改代码。执行成功:
class HomeHeade extends StatelessWidget implements PreferredSizeWidget {
@override
Size get preferredSize => const Size.fromHeight(50);
Widget build(BuildContext context) {
return AppBar(
centerTitle:true,
title:Text('生存日记',style: TextStyle(color: Color(0xFF02020D))),
flexibleSpace: Container(
decoration: BoxDecoration(
gradient: LinearGradient(colors: [
Color(0xFFFAD956),
Colors.white,
], begin: Alignment.topCenter, end: Alignment.bottomCenter),
),
),
);
}
}
标签:BoxDecoration,TextStyle,PreferredSizeWidget,HomeHeade,Color,appBar,subtype,type, 来源: https://blog.csdn.net/a646639956/article/details/113791942