tsacdop-podcast-app-android/lib/home/audiopanel.dart

208 lines
6.4 KiB
Dart

import 'package:flutter/material.dart';
enum SlideDirection { up, down }
class AudioPanel extends StatefulWidget {
final Widget miniPanel;
final Widget expandedPanel;
final double minHeight;
final double maxHeight;
AudioPanel(
{@required this.miniPanel,
@required this.expandedPanel,
this.minHeight = 60,
this.maxHeight = 300,
Key key})
: super(key: key);
@override
_AudioPanelState createState() => _AudioPanelState();
}
class _AudioPanelState extends State<AudioPanel> with TickerProviderStateMixin {
double initSize;
double _startdy;
double _move = 0;
AnimationController _controller;
AnimationController _slowController;
Animation _animation;
SlideDirection _slideDirection;
@override
void initState() {
initSize = widget.minHeight;
_slideDirection = SlideDirection.up;
_controller =
AnimationController(vsync: this, duration: Duration(milliseconds: 50))
..addListener(() {
setState(() {});
});
_slowController =
AnimationController(vsync: this, duration: Duration(milliseconds: 200))
..addListener(() {
setState(() {});
});
_animation =
Tween<double>(begin: initSize, end: initSize).animate(_controller);
super.initState();
}
@override
void dispose() {
_controller.dispose();
_slowController.dispose();
super.dispose();
}
@override
Widget build(BuildContext context) {
return Stack(children: <Widget>[
Container(
child: (_animation.value > widget.minHeight + 30)
? Positioned.fill(
child: GestureDetector(
onTap: () => _backToMini(),
child: Container(
color: Theme.of(context)
.scaffoldBackgroundColor
.withOpacity(0.5),
),
),
)
: Center(),
),
Container(
alignment: Alignment.bottomCenter,
child: GestureDetector(
onVerticalDragStart: (event) => _start(event),
onVerticalDragUpdate: (event) => _update(event),
onVerticalDragEnd: (event) => _end(),
child: Container(
height: (_animation.value >= widget.maxHeight)
? widget.maxHeight
: (_animation.value <= widget.minHeight)
? widget.minHeight
: _animation.value,
child: _animation.value < widget.minHeight + 30
? Container(
color: Theme.of(context).primaryColor,
child: Opacity(
opacity: _animation.value > widget.minHeight
? (widget.minHeight + 30 - _animation.value) / 40
: 1,
child: Container(
child: widget.miniPanel,
),
),
)
: Container(
decoration: BoxDecoration(
color: Theme.of(context).primaryColor,
boxShadow: [
BoxShadow(
offset: Offset(0, -0.5),
blurRadius: 1,
color:
Theme.of(context).brightness == Brightness.light
? Colors.grey[400].withOpacity(0.5)
: Colors.grey[800],
),
],
),
child: SingleChildScrollView(
physics: const NeverScrollableScrollPhysics(),
child: Opacity(
opacity: _animation.value < (widget.maxHeight - 50)
? (_animation.value - widget.minHeight) /
(widget.maxHeight - widget.minHeight - 50)
: 1,
child: Container(
height: widget.maxHeight,
child: widget.expandedPanel,
),
),
),
),
),
),
),
]);
}
_backToMini() {
setState(() {
_animation = Tween<double>(begin: initSize, end: widget.minHeight)
.animate(_slowController);
initSize = widget.minHeight;
});
_slowController.forward();
}
_start(DragStartDetails event) {
setState(() {
_startdy = event.localPosition.dy;
_animation =
Tween<double>(begin: initSize, end: initSize).animate(_controller);
});
_controller.forward();
}
_update(DragUpdateDetails event) {
setState(() {
_move = _startdy - event.localPosition.dy;
_animation = Tween<double>(begin: initSize, end: initSize + _move)
.animate(_controller);
_slideDirection = _move > 0 ? SlideDirection.up : SlideDirection.down;
});
_controller.forward();
}
_end() {
if (_slideDirection == SlideDirection.up) {
if (_move > 20) {
setState(() {
_animation =
Tween<double>(begin: _animation.value, end: widget.maxHeight)
.animate(_slowController);
initSize = widget.maxHeight;
});
_slowController.forward();
} else {
setState(() {
_animation =
Tween<double>(begin: _animation.value, end: widget.minHeight)
.animate(_controller);
initSize = widget.minHeight;
});
_controller.forward();
}
} else if (_slideDirection == SlideDirection.down) {
if (_move > -50) {
setState(() {
_animation =
Tween<double>(begin: _animation.value, end: widget.maxHeight)
.animate(_slowController);
initSize = widget.maxHeight;
});
_slowController.forward();
} else {
setState(() {
_animation =
Tween<double>(begin: _animation.value, end: widget.minHeight)
.animate(_controller);
initSize = widget.minHeight;
});
_controller.forward();
}
}
if (_animation.value >= widget.maxHeight) {
setState(() {
initSize = widget.maxHeight;
});
} else if (_animation.value < widget.minHeight) {
setState(() {
initSize = widget.minHeight;
});
}
}
}