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// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'dart:async';
import 'package:flutter/animation.dart';
import 'basic.dart';
import 'framework.dart';
class SmoothlyResizingOverflowBox extends StatefulComponent {
SmoothlyResizingOverflowBox({
Key key,
this.child,
this.size,
this.duration,
this.curve: Curves.linear
}) : super(key: key) {
assert(duration != null);
assert(curve != null);
}
final Widget child;
final Size size;
final Duration duration;
final Curve curve;
_SmoothlyResizingOverflowBoxState createState() => new _SmoothlyResizingOverflowBoxState();
}
class _SmoothlyResizingOverflowBoxState extends State<SmoothlyResizingOverflowBox> {
ValuePerformance<Size> _size;
void initState() {
super.initState();
_size = new ValuePerformance(
variable: new AnimatedSizeValue(config.size, curve: config.curve),
duration: config.duration
)..addListener(() {
setState(() {});
});
}
void didUpdateConfig(SmoothlyResizingOverflowBox oldConfig) {
_size.duration = config.duration;
_size.variable.curve = config.curve;
if (config.size != oldConfig.size) {
AnimatedSizeValue variable = _size.variable;
variable.begin = variable.value;
variable.end = config.size;
_size.progress = 0.0;
_size.play();
}
}
void dispose() {
_size.stop();
super.dispose();
}
Widget build(BuildContext context) {
return new SizedOverflowBox(
size: _size.value,
child: config.child
);
}
}
class _Entry {
_Entry({
this.child,
this.enterPerformance,
this.enterTransition
});
final Widget child;
final Performance enterPerformance;
final Widget enterTransition;
Size childSize = Size.zero;
Performance exitPerformance;
Widget exitTransition;
Widget get currentTransition => exitTransition ?? enterTransition;
void dispose() {
enterPerformance?.stop();
exitPerformance?.stop();
}
}
typedef Widget TransitionBuilderCallback(PerformanceView performance, Widget child);
class EnterExitTransition extends StatefulComponent {
EnterExitTransition({
Key key,
this.child,
this.duration,
this.curve: Curves.linear,
this.onEnter,
this.onExit
}) : super(key: key) {
assert(child != null);
assert(duration != null);
assert(curve != null);
assert(onEnter != null);
assert(onExit != null);
}
final Widget child;
final Duration duration;
final Curve curve;
final TransitionBuilderCallback onEnter;
final TransitionBuilderCallback onExit;
_EnterExitTransitionState createState() => new _EnterExitTransitionState();
}
class _EnterExitTransitionState extends State<EnterExitTransition> {
final List<_Entry> _entries = new List<_Entry>();
void initState() {
super.initState();
_entries.add(_createEnterTransition());
}
_Entry _createEnterTransition() {
Performance enterPerformance = new Performance(duration: config.duration)..play();
return new _Entry(
child: config.child,
enterPerformance: enterPerformance,
enterTransition: config.onEnter(enterPerformance, new KeyedSubtree(
key: new GlobalKey(),
child: config.child
))
);
}
Future _createExitTransition(_Entry entry) async {
Performance exitPerformance = new Performance(duration: config.duration);
entry
..exitPerformance = exitPerformance
..exitTransition = config.onExit(exitPerformance, entry.enterTransition);
await exitPerformance.play();
if (!mounted)
return;
setState(() {
_entries.remove(entry);
});
}
void didUpdateConfig(EnterExitTransition oldConfig) {
if (config.child.key != oldConfig.child.key) {
_createExitTransition(_entries.last);
_entries.add(_createEnterTransition());
}
}
void dispose() {
for (_Entry entry in new List<_Entry>.from(_entries))
entry.dispose();
super.dispose();
}
Widget build(BuildContext context) {
return new SmoothlyResizingOverflowBox(
size: _entries.last.childSize,
duration: config.duration,
curve: config.curve,
child: new Stack(_entries.map((_Entry entry) {
return new SizeObserver(
key: new ObjectKey(entry),
onSizeChanged: (Size newSize) {
setState(() {
entry.childSize = newSize;
});
},
child: entry.currentTransition
);
}).toList())
);
}
}