text
stringlengths
1
372
),
),
),
),
);
}
<code_end>
congratulations!
you have an animated menu where the appearance of each
list item is staggered, followed by a bottom button that
pops into place.
<topic_end>
<topic_start>
interactive example
<code_start>
import 'package:flutter/material.dart';
void main() {
runApp(
const MaterialApp(
home: ExampleStaggeredAnimations(),
debugShowCheckedModeBanner: false,
),
);
}
class ExampleStaggeredAnimations extends StatefulWidget {
const ExampleStaggeredAnimations({
super.key,
});
@override
State<ExampleStaggeredAnimations> createState() =>
_ExampleStaggeredAnimationsState();
}
class _ExampleStaggeredAnimationsState extends State<ExampleStaggeredAnimations>
with SingleTickerProviderStateMixin {
late AnimationController _drawerSlideController;
@override
void initState() {
super.initState();
_drawerSlideController = AnimationController(
vsync: this,
duration: const duration(milliseconds: 150),
);
}
@override
void dispose() {
_drawerSlideController.dispose();
super.dispose();
}
bool _isDrawerOpen() {
return _drawerSlideController.value == 1.0;
}
bool _isDrawerOpening() {
return _drawerSlideController.status == AnimationStatus.forward;
}
bool _isDrawerClosed() {
return _drawerSlideController.value == 0.0;
}
void _toggleDrawer() {
if (_isdraweropen() || _isDrawerOpening()) {
_drawerSlideController.reverse();
} else {
_drawerSlideController.forward();
}
}
@override
widget build(BuildContext context) {
return scaffold(
backgroundColor: colors.white,
appBar: _buildAppBar(),
body: stack(
children: [
_buildContent(),
_buildDrawer(),
],
),
);
}
PreferredSizeWidget _buildAppBar() {
return AppBar(
title: const text(
'flutter menu',
style: TextStyle(
color: colors.black,
),
),
backgroundColor: colors.transparent,
elevation: 0.0,
automaticallyImplyLeading: false,
actions: [
AnimatedBuilder(
animation: _drawerSlideController,
builder: (context, child) {
return IconButton(
onPressed: _toggleDrawer,
icon: _isDrawerOpen() || _isDrawerOpening()
? const icon(
icons.clear,
color: colors.black,
)
: const icon(