Here's a sketch of how to implement a Speed dial using FloatingActionButton
.
import 'package:flutter/material.dart';
import 'dart:math' as math;
void main() {
runApp(new MyApp());
}
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return new MaterialApp(
home: new MyHomePage(),
);
}
}
class MyHomePage extends StatefulWidget {
@override
State createState() => new MyHomePageState();
}
class MyHomePageState extends State<MyHomePage> with TickerProviderStateMixin {
AnimationController _controller;
static const List<IconData> icons = const [ Icons.sms, Icons.mail, Icons.phone ];
@override
void initState() {
_controller = new AnimationController(
vsync: this,
duration: const Duration(milliseconds: 500),
);
}
Widget build(BuildContext context) {
Color backgroundColor = Theme.of(context).cardColor;
Color foregroundColor = Theme.of(context).accentColor;
return new Scaffold(
appBar: new AppBar(title: new Text('Speed Dial Example')),
floatingActionButton: new Column(
mainAxisSize: MainAxisSize.min,
children: new List.generate(icons.length, (int index) {
Widget child = new Container(
height: 70.0,
width: 56.0,
alignment: FractionalOffset.topCenter,
child: new ScaleTransition(
scale: new CurvedAnimation(
parent: _controller,
curve: new Interval(
0.0,
1.0 - index / icons.length / 2.0,
curve: Curves.easeOut
),
),
child: new FloatingActionButton(
heroTag: null,
backgroundColor: backgroundColor,
mini: true,
child: new Icon(icons[index], color: foregroundColor),
onPressed: () {},
),
),
);
return child;
}).toList()..add(
new FloatingActionButton(
heroTag: null,
child: new AnimatedBuilder(
animation: _controller,
builder: (BuildContext context, Widget child) {
return new Transform(
transform: new Matrix4.rotationZ(_controller.value * 0.5 * math.pi),
alignment: FractionalOffset.center,
child: new Icon(_controller.isDismissed ? Icons.share : Icons.close),
);
},
),
onPressed: () {
if (_controller.isDismissed) {
_controller.forward();
} else {
_controller.reverse();
}
},
),
),
),
);
}
}
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