早上好。
我正在从AppBar更改为SliverAppBar。原始的AppBar在flexibleSpace
中具有渐变,但是现在在SliverAppBar中,我需要向flexibleSpace添加其他内容(用户照片和一些小部件)。因此,当SliverAppBar折叠时,需要以我的渐变显示它,但是当它扩展时,需要显示用户照片等;当然,隐藏渐变。
看这里,我发布了一个视频,其中有条子正在工作,但是还没有渐变:https://drive.google.com/file/d/1DgHjAtrmTXjkb3HB7YrPo90kdFq7Wdao/view
由于flexibleSpace已包含内容,如何将渐变放在SliverAppBar上?我认为方法是在SliverAppBar中使用GlobalKey来检查它是否折叠,并将flexibleSpace代码更改为渐变。
但是我不能,因为我不知道在全局密钥中使用哪种类型。
原始AppBar
AppBar(
title: Text('Meu Perfil'),
flexibleSpace: Container(
decoration: BoxDecoration(
gradient: LinearGradient(
colors: <Color>[
Color(0xff0068b1),
Color(0xff0078C1),
Color(0xff008cd7),
],
),
),
),
leading: IconButton(
icon: Icon(Icons.arrow_back),
onPressed: () => Navigator.pop(context),
),
)
SliverAppBar
SliverAppBar(
title: Text("Meu Perfil"),
expandedHeight: 264,
pinned: true,
flexibleSpace: FlexibleSpaceBar(
collapseMode: CollapseMode.parallax,
background: Container(
color: Colors.white,
child: Stack(
children: <Widget>[
_userPhoto(),
_capturePhoto(),
],
),
),
),
leading: IconButton(
icon: Icon(Icons.arrow_back),
onPressed: () => Navigator.pop(context),
),
)
SliverAppBar(
expandedHeight: 200.0,
floating: false,
pinned: true,
flexibleSpace: FlexibleSpaceBar(
centerTitle: true,
title: Text("Collapsing Toolbar", style: TextStyle(color: Colors.white, fontSize: 16.0, )),
background: Stack(
fit: StackFit.expand,
children: [
Image.network(
'https://flutter.github.io/assets-for-api-docs/assets/widgets/owl-2.jpg',
fit: BoxFit.cover,
),
DecoratedBox(
decoration: BoxDecoration(
gradient: LinearGradient(
begin: Alignment(0.0, 0.5),
end: Alignment(0.0, 0.0),
colors: [
Color(0x60000000),
Color(0x00000000),
]
)
),
),
],
),
),
),
已解决!!
而不是在FlexibleSpaceBar中添加渐变,解决方案将其包装在Container或DecoratedBox中,因此,当SliverAppBar展开时,FlexibleSpacebar的内容将忽略渐变……当折叠时,内容将隐藏并离开容器与渐变...
SliverAppBar(
title: Text("Meu Perfil"),
elevation: 10,
expandedHeight: 264,
pinned: true,
flexibleSpace: DecoratedBox(
decoration: BoxDecoration(
gradient: LinearGradient(
colors: <Color>[
Color(0xff0068b1),
Color(0xff0078C1),
Color(0xff008cd7),
],
),
),
child: FlexibleSpaceBar(
collapseMode: CollapseMode.parallax,
background: Container(
color: Colors.white,
child: Stack(
children: <Widget>[
_userPhoto(),
_sliverAppBarBottom(),
],
),
),
),
),
leading: IconButton(
icon: Icon(Icons.arrow_back),
onPressed: () => Navigator.pop(context),
),
)