您最多选择25个主题
主题必须以中文或者字母或数字开头，可以包含连字符 (-)，并且长度不得超过35个字符
394 行
16 KiB
394 行
16 KiB
using System;
|
|
using System.Collections.Generic;
|
|
using Unity.UIWidgets.animation;
|
|
using Unity.UIWidgets.async;
|
|
using Unity.UIWidgets.foundation;
|
|
using Unity.UIWidgets.painting;
|
|
using Unity.UIWidgets.ui;
|
|
using Unity.UIWidgets.widgets;
|
|
using UnityEngine;
|
|
using Color = Unity.UIWidgets.ui.Color;
|
|
|
|
namespace Unity.UIWidgets.material {
|
|
class RefreshIndicatorUtils {
|
|
public const float _kDragContainerExtentPercentage = 0.25f;
|
|
|
|
public const float _kDragSizeFactorLimit = 1.5f;
|
|
|
|
public static readonly TimeSpan _kIndicatorSnapDuration = new TimeSpan(0, 0, 0, 0, 150);
|
|
|
|
public static readonly TimeSpan _kIndicatorScaleDuration = new TimeSpan(0, 0, 0, 0, 200);
|
|
}
|
|
|
|
public delegate Future RefreshCallback();
|
|
|
|
enum _RefreshIndicatorMode {
|
|
drag, // Pointer is down.
|
|
armed, // Dragged far enough that an up event will run the onRefresh callback.
|
|
snap, // Animating to the indicator"s final "displacement".
|
|
refresh, // Running the refresh callback.
|
|
done, // Animating the indicator"s fade-out after refreshing.
|
|
canceled, // Animating the indicator"s fade-out after not arming.
|
|
}
|
|
|
|
public class RefreshIndicator : StatefulWidget {
|
|
public RefreshIndicator(
|
|
Key key = null,
|
|
Widget child = null,
|
|
float displacement = 40.0f,
|
|
RefreshCallback onRefresh = null,
|
|
Color color = null,
|
|
Color backgroundColor = null,
|
|
ScrollNotificationPredicate notificationPredicate = null,
|
|
float strokenWidth = 2.0f
|
|
) : base(key: key) {
|
|
D.assert(child != null);
|
|
D.assert(onRefresh != null);
|
|
this.child = child;
|
|
this.displacement = displacement;
|
|
this.onRefresh = onRefresh;
|
|
this.color = color;
|
|
this.backgroundColor = backgroundColor;
|
|
this.notificationPredicate = notificationPredicate ?? ScrollNotification.defaultScrollNotificationPredicate;
|
|
}
|
|
|
|
public readonly Widget child;
|
|
|
|
public readonly float displacement;
|
|
|
|
public readonly RefreshCallback onRefresh;
|
|
|
|
public readonly Color color;
|
|
|
|
public readonly Color backgroundColor;
|
|
|
|
public readonly ScrollNotificationPredicate notificationPredicate;
|
|
|
|
public readonly float strokeWidth;
|
|
|
|
public override State createState() {
|
|
return new RefreshIndicatorState();
|
|
}
|
|
}
|
|
|
|
public class RefreshIndicatorState : TickerProviderStateMixin<RefreshIndicator> {
|
|
AnimationController _positionController;
|
|
AnimationController _scaleController;
|
|
Animation<float> _positionFactor;
|
|
Animation<float> _scaleFactor;
|
|
Animation<float> _value;
|
|
Animation<Color> _valueColor;
|
|
|
|
_RefreshIndicatorMode? _mode;
|
|
Future _pendingRefreshFuture;
|
|
bool? _isIndicatorAtTop;
|
|
float? _dragOffset;
|
|
|
|
static readonly Animatable<float> _threeQuarterTween = new FloatTween(begin: 0.0f, end: 0.75f);
|
|
|
|
static readonly Animatable<float> _kDragSizeFactorLimitTween =
|
|
new FloatTween(begin: 0.0f, end: RefreshIndicatorUtils._kDragSizeFactorLimit);
|
|
|
|
static readonly Animatable<float> _oneToZeroTween = new FloatTween(begin: 1.0f, end: 0.0f);
|
|
|
|
public RefreshIndicatorState() {
|
|
}
|
|
|
|
public override void initState() {
|
|
base.initState();
|
|
_positionController = new AnimationController(vsync: this);
|
|
_positionFactor = _positionController.drive(_kDragSizeFactorLimitTween);
|
|
_value =
|
|
_positionController
|
|
.drive(_threeQuarterTween); // The "value" of the circular progress indicator during a drag.
|
|
|
|
_scaleController = new AnimationController(vsync: this);
|
|
_scaleFactor = _scaleController.drive(_oneToZeroTween);
|
|
}
|
|
|
|
public override void didChangeDependencies() {
|
|
ThemeData theme = Theme.of(context);
|
|
_valueColor = _positionController.drive(
|
|
new ColorTween(
|
|
begin: (widget.color ?? theme.accentColor).withOpacity(0.0f),
|
|
end: (widget.color ?? theme.accentColor).withOpacity(1.0f)
|
|
).chain(new CurveTween(
|
|
curve: new Interval(0.0f, 1.0f / RefreshIndicatorUtils._kDragSizeFactorLimit)
|
|
))
|
|
);
|
|
base.didChangeDependencies();
|
|
}
|
|
|
|
public override void dispose() {
|
|
_positionController.dispose();
|
|
_scaleController.dispose();
|
|
base.dispose();
|
|
}
|
|
|
|
bool _handleScrollNotification(ScrollNotification notification) {
|
|
if (!widget.notificationPredicate(notification)) {
|
|
return false;
|
|
}
|
|
|
|
if (notification is ScrollStartNotification && notification.metrics.extentBefore() == 0.0f &&
|
|
_mode == null && _start(notification.metrics.axisDirection)) {
|
|
setState(() => { _mode = _RefreshIndicatorMode.drag; });
|
|
return false;
|
|
}
|
|
|
|
bool? indicatorAtTopNow = null;
|
|
switch (notification.metrics.axisDirection) {
|
|
case AxisDirection.down:
|
|
indicatorAtTopNow = true;
|
|
break;
|
|
case AxisDirection.up:
|
|
indicatorAtTopNow = false;
|
|
break;
|
|
case AxisDirection.left:
|
|
case AxisDirection.right:
|
|
indicatorAtTopNow = null;
|
|
break;
|
|
}
|
|
|
|
if (indicatorAtTopNow != _isIndicatorAtTop) {
|
|
if (_mode == _RefreshIndicatorMode.drag || _mode == _RefreshIndicatorMode.armed) {
|
|
_dismiss(_RefreshIndicatorMode.canceled);
|
|
}
|
|
}
|
|
else if (notification is ScrollUpdateNotification) {
|
|
if (_mode == _RefreshIndicatorMode.drag || _mode == _RefreshIndicatorMode.armed) {
|
|
if (notification.metrics.extentBefore() > 0.0f) {
|
|
_dismiss(_RefreshIndicatorMode.canceled);
|
|
}
|
|
else {
|
|
_dragOffset -= (notification as ScrollUpdateNotification).scrollDelta;
|
|
_checkDragOffset(notification.metrics.viewportDimension);
|
|
}
|
|
}
|
|
|
|
if (_mode == _RefreshIndicatorMode.armed &&
|
|
(notification as ScrollUpdateNotification).dragDetails == null) {
|
|
_show();
|
|
}
|
|
}
|
|
else if (notification is OverscrollNotification) {
|
|
if (_mode == _RefreshIndicatorMode.drag || _mode == _RefreshIndicatorMode.armed) {
|
|
_dragOffset -= (notification as OverscrollNotification).overscroll / 2.0f;
|
|
_checkDragOffset(notification.metrics.viewportDimension);
|
|
}
|
|
}
|
|
else if (notification is ScrollEndNotification) {
|
|
switch (_mode) {
|
|
case _RefreshIndicatorMode.armed:
|
|
_show();
|
|
break;
|
|
case _RefreshIndicatorMode.drag:
|
|
_dismiss(_RefreshIndicatorMode.canceled);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
bool _handleGlowNotification(OverscrollIndicatorNotification notification) {
|
|
if (notification.depth != 0 || !notification.leading) {
|
|
return false;
|
|
}
|
|
|
|
if (_mode == _RefreshIndicatorMode.drag) {
|
|
notification.disallowGlow();
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
bool _start(AxisDirection direction) {
|
|
D.assert(_mode == null);
|
|
D.assert(_isIndicatorAtTop == null);
|
|
D.assert(_dragOffset == null);
|
|
switch (direction) {
|
|
case AxisDirection.down:
|
|
_isIndicatorAtTop = true;
|
|
break;
|
|
case AxisDirection.up:
|
|
_isIndicatorAtTop = false;
|
|
break;
|
|
case AxisDirection.left:
|
|
case AxisDirection.right:
|
|
_isIndicatorAtTop = null;
|
|
return false;
|
|
}
|
|
|
|
_dragOffset = 0.0f;
|
|
_scaleController.setValue(0.0f);
|
|
_positionController.setValue(0.0f);
|
|
return true;
|
|
}
|
|
|
|
void _checkDragOffset(float containerExtent) {
|
|
D.assert(_mode == _RefreshIndicatorMode.drag || _mode == _RefreshIndicatorMode.armed);
|
|
float? newValue = _dragOffset /
|
|
(containerExtent * RefreshIndicatorUtils._kDragContainerExtentPercentage);
|
|
if (_mode == _RefreshIndicatorMode.armed) {
|
|
newValue = Mathf.Max(newValue ?? 0.0f, 1.0f / RefreshIndicatorUtils._kDragSizeFactorLimit);
|
|
}
|
|
|
|
_positionController.setValue(newValue?.clamp(0.0f, 1.0f) ?? 0.0f); // this triggers various rebuilds
|
|
if (_mode == _RefreshIndicatorMode.drag && _valueColor.value.alpha == 0xFF) {
|
|
_mode = _RefreshIndicatorMode.armed;
|
|
}
|
|
}
|
|
|
|
Future _dismiss(_RefreshIndicatorMode newMode) {
|
|
D.assert(newMode == _RefreshIndicatorMode.canceled || newMode == _RefreshIndicatorMode.done);
|
|
setState(() => { _mode = newMode; });
|
|
switch (_mode) {
|
|
case _RefreshIndicatorMode.done:
|
|
return _scaleController
|
|
.animateTo(1.0f, duration: RefreshIndicatorUtils._kIndicatorScaleDuration).then((value) => {
|
|
if (mounted && _mode == newMode) {
|
|
_dragOffset = null;
|
|
_isIndicatorAtTop = null;
|
|
setState(() => { _mode = null; });
|
|
}
|
|
});
|
|
case _RefreshIndicatorMode.canceled:
|
|
return _positionController
|
|
.animateTo(0.0f, duration: RefreshIndicatorUtils._kIndicatorScaleDuration).then((value) => {
|
|
if (mounted && _mode == newMode) {
|
|
_dragOffset = null;
|
|
_isIndicatorAtTop = null;
|
|
setState(() => { _mode = null; });
|
|
}
|
|
});
|
|
default:
|
|
throw new Exception("Unknown refresh indicator mode: " + _mode);
|
|
}
|
|
}
|
|
|
|
void _show() {
|
|
D.assert(_mode != _RefreshIndicatorMode.refresh);
|
|
D.assert(_mode != _RefreshIndicatorMode.snap);
|
|
Completer completer = Completer.create();
|
|
_pendingRefreshFuture = completer.future;
|
|
_mode = _RefreshIndicatorMode.snap;
|
|
_positionController
|
|
.animateTo(1.0f / RefreshIndicatorUtils._kDragSizeFactorLimit,
|
|
duration: RefreshIndicatorUtils._kIndicatorSnapDuration)
|
|
.then((value) => {
|
|
if (mounted && _mode == _RefreshIndicatorMode.snap) {
|
|
D.assert(widget.onRefresh != null);
|
|
setState(() => { _mode = _RefreshIndicatorMode.refresh; });
|
|
|
|
Future refreshResult = widget.onRefresh();
|
|
D.assert(() => {
|
|
if (refreshResult == null) {
|
|
UIWidgetsError.reportError(new UIWidgetsErrorDetails(
|
|
exception: new UIWidgetsError(
|
|
"The onRefresh callback returned null.\n" +
|
|
"The RefreshIndicator onRefresh callback must return a Promise."
|
|
),
|
|
context: new ErrorDescription("when calling onRefresh"),
|
|
library: "material library"
|
|
));
|
|
}
|
|
|
|
return true;
|
|
});
|
|
if (refreshResult == null) {
|
|
return;
|
|
}
|
|
|
|
refreshResult.whenComplete(() => {
|
|
if (mounted && _mode == _RefreshIndicatorMode.refresh) {
|
|
completer.complete();
|
|
_dismiss(_RefreshIndicatorMode.done);
|
|
}
|
|
});
|
|
}
|
|
});
|
|
}
|
|
|
|
public Future show(bool atTop = true) {
|
|
if (_mode != _RefreshIndicatorMode.refresh && _mode != _RefreshIndicatorMode.snap) {
|
|
if (_mode == null) {
|
|
_start(atTop ? AxisDirection.down : AxisDirection.up);
|
|
}
|
|
|
|
_show();
|
|
}
|
|
|
|
return _pendingRefreshFuture;
|
|
}
|
|
|
|
public override Widget build(BuildContext context) {
|
|
D.assert(material_.debugCheckHasMaterialLocalizations(context));
|
|
Widget child = new NotificationListener<ScrollNotification>(
|
|
onNotification: _handleScrollNotification,
|
|
child: new NotificationListener<OverscrollIndicatorNotification>(
|
|
onNotification: _handleGlowNotification,
|
|
child: widget.child
|
|
)
|
|
);
|
|
D.assert(() => {
|
|
if (_mode == null) {
|
|
D.assert(_dragOffset == null);
|
|
D.assert(_isIndicatorAtTop == null);
|
|
}
|
|
else {
|
|
D.assert(_dragOffset != null);
|
|
D.assert(_isIndicatorAtTop != null);
|
|
}
|
|
|
|
return true;
|
|
});
|
|
|
|
bool showIndeterminateIndicator =
|
|
_mode == _RefreshIndicatorMode.refresh || _mode == _RefreshIndicatorMode.done;
|
|
|
|
List<Widget> children = new List<Widget> {child};
|
|
if (_mode != null) {
|
|
children.Add(new Positioned(
|
|
top: _isIndicatorAtTop == true ? 0.0f : (float?) null,
|
|
bottom: _isIndicatorAtTop != true ? 0.0f : (float?) null,
|
|
left: 0.0f,
|
|
right: 0.0f,
|
|
child: new SizeTransition(
|
|
axisAlignment: _isIndicatorAtTop == true ? 1.0f : -1.0f,
|
|
sizeFactor: _positionFactor, // this is what brings it down
|
|
child: new Container(
|
|
padding: _isIndicatorAtTop == true
|
|
? EdgeInsets.only(top: widget.displacement)
|
|
: EdgeInsets.only(bottom: widget.displacement),
|
|
alignment: _isIndicatorAtTop == true
|
|
? Alignment.topCenter
|
|
: Alignment.bottomCenter,
|
|
child: new ScaleTransition(
|
|
scale: _scaleFactor,
|
|
child: new AnimatedBuilder(
|
|
animation: _positionController,
|
|
builder: (BuildContext _context, Widget _child) => {
|
|
return new RefreshProgressIndicator(
|
|
value: showIndeterminateIndicator ? (float?) null : _value.value,
|
|
valueColor: _valueColor,
|
|
backgroundColor: widget.backgroundColor,
|
|
strokeWidth: widget.strokeWidth
|
|
);
|
|
}
|
|
)
|
|
)
|
|
)
|
|
)
|
|
));
|
|
}
|
|
|
|
return new Stack(
|
|
children: children
|
|
);
|
|
}
|
|
}
|
|
}
|