Flutter: How to set the height of a SliverAppBar? - layout

Question

I am trying to use SliverAppBar. The layout was fine on the phone devices. However, when I use the iPad to test the layout, it seems that the height of the AppBar does not change, and it could not show the title text properly .
When I collasped the AppBar:
I tried too add the bottom attribute to the SliverAppBar, but it doesn't works too.
bottom: PreferredSize(
preferredSize: Size.fromHeight(60.0),
child: Text(''),
),
and the result looks like this:
the title text is still restricted with an invisible height.
my code:
new SliverAppBar(
expandedHeight: Adapt.px(220.0),
floating: false,
elevation: 0.0,
pinned: true,
primary: true,
centerTitle: true,
title: Text("TITLE",
style: TextStyle(
color: Colors.white,
fontSize: Adapt.px(45.0),
fontFamily: "pinfon",
fontWeight: FontWeight.w900,
letterSpacing: 1.0)),
backgroundColor: Colors.black45,
brightness: Brightness.dark,
bottom: PreferredSize(
preferredSize: Size.fromHeight(60.0),
child: Text(''),
),
flexibleSpace: new FlexibleSpaceBar(
background: Opacity(
opacity: 0.5,
child: new Stack(
fit: StackFit.expand,
children: <Widget>[
new Image.asset(
"assets/images/back.jpg",
fit: BoxFit.fitWidth,
),
],
),
),
),
),

Answer 1

I have tested the sample code you have provided and it seems that the layout is working fine when with an iPad Air - 4th generation - 14.0 emulator.
Though, I'm not able to see your complete code. I've just reused the minimal code you have provided and created a complete example to be able to see the output.
Here is my sample code:
import 'package:flutter/material.dart';
void main() => runApp(SilverAppBarExample());
class SilverAppBarExample extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
body: CustomScrollView(
slivers: <Widget>[
new SliverAppBar(
expandedHeight: 220.0,
floating: false,
elevation: 0.0,
pinned: true,
primary: true,
centerTitle: true,
title: Text("TITLE",
style: TextStyle(
color: Colors.white,
fontSize: 45.0,
fontFamily: "pinfon",
fontWeight: FontWeight.w900,
letterSpacing: 1.0)),
backgroundColor: Colors.black45,
brightness: Brightness.dark,
bottom: PreferredSize(
preferredSize: Size.fromHeight(60.0),
child: Text(''),
),
flexibleSpace: new FlexibleSpaceBar(
background: Opacity(
opacity: 0.5,
child: new Stack(
fit: StackFit.expand,
children: <Widget>[
new Image.asset(
"assets/background.jpg",
fit: BoxFit.fitWidth,
),
],
),
),
),
),
new SliverList(
delegate: new SliverChildListDelegate(_buildList(50))),
],
),
),
);
}
List _buildList(int count) {
List<Widget> listItems = List();
for (int i = 0; i < count; i++) {
listItems.add(new Padding(
padding: new EdgeInsets.all(20.0),
child: new Text('Item ${i.toString()}',
style: new TextStyle(fontSize: 25.0))));
}
return listItems;
}
}
Output using iPad Air - 4th generation - 14.0 emulator
Expanded:
Shrinked:
It seems that the SliverAppBar is working fine.
I've also tested it in an iPhone emulator for verification.
iPhone SE - 2nd generation - 14.0
Expanded:
Shrinked:
Here is a live output:
Maybe if you could provide the whole code you've created we will be able to check it on our end.