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1453 行
54 KiB
1453 行
54 KiB
using System;
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using System.Collections.Generic;
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using System.Linq;
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using RSG;
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using Unity.UIWidgets.animation;
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using Unity.UIWidgets.foundation;
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using Unity.UIWidgets.gestures;
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using Unity.UIWidgets.painting;
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using Unity.UIWidgets.physics;
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using Unity.UIWidgets.rendering;
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using Unity.UIWidgets.scheduler;
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using Unity.UIWidgets.ui;
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using UnityEngine;
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using Color = Unity.UIWidgets.ui.Color;
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namespace Unity.UIWidgets.widgets {
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public delegate List<Widget> NestedScrollViewHeaderSliversBuilder(BuildContext context, bool innerBoxIsScrolled);
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public class NestedScrollView : StatefulWidget {
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public NestedScrollView(
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Key key = null,
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ScrollController controller = null,
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Axis scrollDirection = Axis.vertical,
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bool reverse = false,
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ScrollPhysics physics = null,
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NestedScrollViewHeaderSliversBuilder headerSliverBuilder = null,
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Widget body = null,
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DragStartBehavior dragStartBehavior = DragStartBehavior.down
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) : base(key: key) {
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D.assert(headerSliverBuilder != null);
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D.assert(body != null);
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this.controller = controller;
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this.scrollDirection = scrollDirection;
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this.reverse = reverse;
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this.physics = physics;
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this.headerSliverBuilder = headerSliverBuilder;
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this.body = body;
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this.dragStartBehavior = dragStartBehavior;
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}
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public readonly ScrollController controller;
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public readonly Axis scrollDirection;
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public readonly bool reverse;
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public readonly ScrollPhysics physics;
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public readonly NestedScrollViewHeaderSliversBuilder headerSliverBuilder;
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public readonly Widget body;
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public readonly DragStartBehavior dragStartBehavior;
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public static SliverOverlapAbsorberHandle sliverOverlapAbsorberHandleFor(BuildContext context) {
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_InheritedNestedScrollView target =
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(_InheritedNestedScrollView) context.inheritFromWidgetOfExactType(typeof(_InheritedNestedScrollView));
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D.assert(target != null,
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() => {
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return
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"NestedScrollView.sliverOverlapAbsorberHandleFor must be called with a context that contains a NestedScrollView.";
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});
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return target.state._absorberHandle;
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}
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internal List<Widget> _buildSlivers(BuildContext context, ScrollController innerController,
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bool bodyIsScrolled) {
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List<Widget> slivers = new List<Widget> { };
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slivers.AddRange(this.headerSliverBuilder(context, bodyIsScrolled));
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slivers.Add(new SliverFillRemaining(
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child: new PrimaryScrollController(
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controller: innerController,
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child: this.body
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)
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));
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return slivers;
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}
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public override State createState() {
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return new _NestedScrollViewState();
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}
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}
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class _NestedScrollViewState : State<NestedScrollView> {
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internal SliverOverlapAbsorberHandle _absorberHandle = new SliverOverlapAbsorberHandle();
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_NestedScrollCoordinator _coordinator;
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public override void initState() {
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base.initState();
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this._coordinator =
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new _NestedScrollCoordinator(this, this.widget.controller, this._handleHasScrolledBodyChanged);
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}
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public override void didChangeDependencies() {
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base.didChangeDependencies();
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this._coordinator.setParent(this.widget.controller);
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}
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public override void didUpdateWidget(StatefulWidget _oldWidget) {
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NestedScrollView oldWidget = _oldWidget as NestedScrollView;
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base.didUpdateWidget(oldWidget);
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if (oldWidget.controller != this.widget.controller) {
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this._coordinator.setParent(this.widget.controller);
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}
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}
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public override void dispose() {
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this._coordinator.dispose();
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this._coordinator = null;
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base.dispose();
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}
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bool _lastHasScrolledBody;
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void _handleHasScrolledBodyChanged() {
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if (!this.mounted) {
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return;
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}
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bool newHasScrolledBody = this._coordinator.hasScrolledBody;
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if (this._lastHasScrolledBody != newHasScrolledBody) {
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this.setState(() => { });
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}
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}
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public override Widget build(BuildContext context) {
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return new _InheritedNestedScrollView(
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state: this,
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child: new Builder(
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builder: (BuildContext _context) => {
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this._lastHasScrolledBody = this._coordinator.hasScrolledBody;
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return new _NestedScrollViewCustomScrollView(
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dragStartBehavior: this.widget.dragStartBehavior,
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scrollDirection: this.widget.scrollDirection,
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reverse: this.widget.reverse,
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physics: this.widget.physics != null
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? this.widget.physics.applyTo(new ClampingScrollPhysics())
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: new ClampingScrollPhysics(),
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controller: this._coordinator._outerController,
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slivers: this.widget._buildSlivers(
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_context, this._coordinator._innerController, this._lastHasScrolledBody
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),
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handle: this._absorberHandle
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);
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}
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)
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);
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}
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}
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class _NestedScrollViewCustomScrollView : CustomScrollView {
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public _NestedScrollViewCustomScrollView(
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Axis scrollDirection,
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bool reverse,
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ScrollPhysics physics,
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ScrollController controller,
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List<Widget> slivers,
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SliverOverlapAbsorberHandle handle,
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DragStartBehavior dragStartBehavior = DragStartBehavior.down
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) : base(
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scrollDirection: scrollDirection,
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reverse: reverse,
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physics: physics,
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controller: controller,
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slivers: slivers,
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dragStartBehavior: dragStartBehavior
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) {
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this.handle = handle;
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}
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public readonly SliverOverlapAbsorberHandle handle;
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protected override Widget buildViewport(
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BuildContext context,
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ViewportOffset offset,
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AxisDirection axisDirection,
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List<Widget> slivers
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) {
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D.assert(!this.shrinkWrap);
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return new NestedScrollViewViewport(
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axisDirection: axisDirection,
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offset: offset,
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slivers: slivers,
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handle: this.handle
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);
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}
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}
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class _InheritedNestedScrollView : InheritedWidget {
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public _InheritedNestedScrollView(
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Key key = null,
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_NestedScrollViewState state = null,
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Widget child = null
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) : base(key: key, child: child) {
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D.assert(state != null);
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D.assert(child != null);
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this.state = state;
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}
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public readonly _NestedScrollViewState state;
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public override bool updateShouldNotify(InheritedWidget _old) {
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_InheritedNestedScrollView old = _old as _InheritedNestedScrollView;
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return this.state != old.state;
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}
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}
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class _NestedScrollMetrics : FixedScrollMetrics {
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public _NestedScrollMetrics(
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float minScrollExtent,
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float maxScrollExtent,
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float pixels,
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float viewportDimension,
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AxisDirection axisDirection,
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float minRange,
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float maxRange,
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float correctionOffset
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) : base(
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minScrollExtent: minScrollExtent,
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maxScrollExtent: maxScrollExtent,
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pixels: pixels,
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viewportDimension: viewportDimension,
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axisDirection: axisDirection
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) {
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this.minRange = minRange;
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this.maxRange = maxRange;
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this.correctionOffset = correctionOffset;
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}
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public _NestedScrollMetrics copyWith(
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float? minScrollExtent = null,
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float? maxScrollExtent = null,
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float? pixels = null,
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float? viewportDimension = null,
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AxisDirection? axisDirection = null,
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float? minRange = null,
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float? maxRange = null,
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float? correctionOffset = null
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) {
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return new _NestedScrollMetrics(
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minScrollExtent: minScrollExtent ?? this.minScrollExtent,
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maxScrollExtent: maxScrollExtent ?? this.maxScrollExtent,
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pixels: pixels ?? this.pixels,
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viewportDimension: viewportDimension ?? this.viewportDimension,
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axisDirection: axisDirection ?? this.axisDirection,
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minRange: minRange ?? this.minRange,
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maxRange: maxRange ?? this.maxRange,
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correctionOffset: correctionOffset ?? this.correctionOffset
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);
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}
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public readonly float minRange;
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public readonly float maxRange;
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public readonly float correctionOffset;
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}
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delegate ScrollActivity _NestedScrollActivityGetter(_NestedScrollPosition position);
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class _NestedScrollCoordinator : ScrollActivityDelegate, ScrollHoldController {
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public _NestedScrollCoordinator(
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_NestedScrollViewState _state,
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ScrollController _parent,
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VoidCallback _onHasScrolledBodyChanged) {
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float initialScrollOffset = _parent?.initialScrollOffset ?? 0.0f;
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this._outerController =
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new _NestedScrollController(this, initialScrollOffset: initialScrollOffset, debugLabel: "outer");
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this._innerController = new _NestedScrollController(this, initialScrollOffset: 0.0f, debugLabel: "inner");
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this._state = _state;
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this._parent = _parent;
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this._onHasScrolledBodyChanged = _onHasScrolledBodyChanged;
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}
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public readonly _NestedScrollViewState _state;
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ScrollController _parent;
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public readonly VoidCallback _onHasScrolledBodyChanged;
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internal _NestedScrollController _outerController;
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internal _NestedScrollController _innerController;
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_NestedScrollPosition _outerPosition {
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get {
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if (!this._outerController.hasClients) {
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return null;
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}
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return this._outerController.nestedPositions.Single();
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}
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}
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IEnumerable<_NestedScrollPosition> _innerPositions {
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get { return this._innerController.nestedPositions; }
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}
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public bool canScrollBody {
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get {
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_NestedScrollPosition outer = this._outerPosition;
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if (outer == null) {
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return true;
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}
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return outer.haveDimensions && outer.extentAfter() == 0.0f;
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}
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}
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public bool hasScrolledBody {
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get {
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foreach (_NestedScrollPosition position in this._innerPositions) {
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if (position.pixels > position.minScrollExtent) {
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return true;
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}
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}
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return false;
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}
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}
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public void updateShadow() {
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if (this._onHasScrolledBodyChanged != null) {
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this._onHasScrolledBodyChanged();
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}
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}
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public ScrollDirection userScrollDirection {
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get { return this._userScrollDirection; }
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}
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ScrollDirection _userScrollDirection = ScrollDirection.idle;
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public void updateUserScrollDirection(ScrollDirection value) {
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if (this.userScrollDirection == value) {
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return;
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}
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this._userScrollDirection = value;
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this._outerPosition.didUpdateScrollDirection(value);
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foreach (_NestedScrollPosition position in this._innerPositions) {
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position.didUpdateScrollDirection(value);
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}
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}
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ScrollDragController _currentDrag;
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public void beginActivity(ScrollActivity newOuterActivity, _NestedScrollActivityGetter innerActivityGetter) {
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this._outerPosition.beginActivity(newOuterActivity);
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bool scrolling = newOuterActivity.isScrolling;
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foreach (_NestedScrollPosition position in this._innerPositions) {
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ScrollActivity newInnerActivity = innerActivityGetter(position);
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position.beginActivity(newInnerActivity);
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scrolling = scrolling && newInnerActivity.isScrolling;
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}
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this._currentDrag?.dispose();
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this._currentDrag = null;
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if (!scrolling) {
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this.updateUserScrollDirection(ScrollDirection.idle);
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}
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}
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public AxisDirection axisDirection {
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get { return this._outerPosition.axisDirection; }
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}
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static IdleScrollActivity _createIdleScrollActivity(_NestedScrollPosition position) {
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return new IdleScrollActivity(position);
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}
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public void goIdle() {
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this.beginActivity(_createIdleScrollActivity(this._outerPosition), _createIdleScrollActivity);
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}
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public void goBallistic(float velocity) {
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this.beginActivity(this.createOuterBallisticScrollActivity(velocity),
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(_NestedScrollPosition position) => this.createInnerBallisticScrollActivity(position, velocity)
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);
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}
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public ScrollActivity createOuterBallisticScrollActivity(float velocity) {
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_NestedScrollPosition innerPosition = null;
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if (velocity != 0.0f) {
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foreach (_NestedScrollPosition position in this._innerPositions) {
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if (innerPosition != null) {
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if (velocity > 0.0f) {
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if (innerPosition.pixels < position.pixels) {
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continue;
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}
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}
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else {
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D.assert(velocity < 0.0f);
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if (innerPosition.pixels > position.pixels) {
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continue;
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}
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}
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}
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innerPosition = position;
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}
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}
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if (innerPosition == null) {
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return this._outerPosition.createBallisticScrollActivity(
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this._outerPosition.physics.createBallisticSimulation(this._outerPosition, velocity),
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mode: _NestedBallisticScrollActivityMode.independent
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);
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}
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_NestedScrollMetrics metrics = this._getMetrics(innerPosition, velocity);
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return this._outerPosition.createBallisticScrollActivity(
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this._outerPosition.physics.createBallisticSimulation(metrics, velocity),
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mode: _NestedBallisticScrollActivityMode.outer,
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metrics: metrics
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);
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}
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protected internal ScrollActivity createInnerBallisticScrollActivity(_NestedScrollPosition position,
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float velocity) {
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return position.createBallisticScrollActivity(
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position.physics.createBallisticSimulation(
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velocity == 0 ? (ScrollMetrics) position : this._getMetrics(position, velocity),
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velocity
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),
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mode: _NestedBallisticScrollActivityMode.inner
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);
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}
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_NestedScrollMetrics _getMetrics(_NestedScrollPosition innerPosition, float velocity) {
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D.assert(innerPosition != null);
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float pixels, minRange, maxRange, correctionOffset, extra;
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if (innerPosition.pixels == innerPosition.minScrollExtent) {
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pixels = this._outerPosition.pixels.clamp(this._outerPosition.minScrollExtent,
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this._outerPosition.maxScrollExtent); // TODO(ianh): gracefully handle out-of-range outer positions
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minRange = this._outerPosition.minScrollExtent;
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maxRange = this._outerPosition.maxScrollExtent;
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D.assert(minRange <= maxRange);
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correctionOffset = 0.0f;
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extra = 0.0f;
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}
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else {
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D.assert(innerPosition.pixels != innerPosition.minScrollExtent);
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if (innerPosition.pixels < innerPosition.minScrollExtent) {
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pixels = innerPosition.pixels - innerPosition.minScrollExtent + this._outerPosition.minScrollExtent;
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}
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else {
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D.assert(innerPosition.pixels > innerPosition.minScrollExtent);
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pixels = innerPosition.pixels - innerPosition.minScrollExtent + this._outerPosition.maxScrollExtent;
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}
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if ((velocity > 0.0f) && (innerPosition.pixels > innerPosition.minScrollExtent)) {
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extra = this._outerPosition.maxScrollExtent - this._outerPosition.pixels;
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D.assert(extra >= 0.0f);
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minRange = pixels;
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maxRange = pixels + extra;
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D.assert(minRange <= maxRange);
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correctionOffset = this._outerPosition.pixels - pixels;
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}
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else if ((velocity < 0.0f) && (innerPosition.pixels < innerPosition.minScrollExtent)) {
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extra = this._outerPosition.pixels - this._outerPosition.minScrollExtent;
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D.assert(extra >= 0.0f);
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minRange = pixels - extra;
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maxRange = pixels;
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D.assert(minRange <= maxRange);
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correctionOffset = this._outerPosition.pixels - pixels;
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}
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else {
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if (velocity > 0.0f) {
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extra = this._outerPosition.minScrollExtent - this._outerPosition.pixels;
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}
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else {
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D.assert(velocity < 0.0f);
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extra = this._outerPosition.pixels -
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(this._outerPosition.maxScrollExtent - this._outerPosition.minScrollExtent);
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}
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D.assert(extra <= 0.0f);
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minRange = this._outerPosition.minScrollExtent;
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maxRange = this._outerPosition.maxScrollExtent + extra;
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D.assert(minRange <= maxRange);
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correctionOffset = 0.0f;
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}
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}
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return new _NestedScrollMetrics(
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minScrollExtent: this._outerPosition.minScrollExtent,
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maxScrollExtent: this._outerPosition.maxScrollExtent + innerPosition.maxScrollExtent -
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innerPosition.minScrollExtent + extra,
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pixels: pixels,
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viewportDimension: this._outerPosition.viewportDimension,
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axisDirection: this._outerPosition.axisDirection,
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minRange: minRange,
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maxRange: maxRange,
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correctionOffset: correctionOffset
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);
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}
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public float unnestOffset(float value, _NestedScrollPosition source) {
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if (source == this._outerPosition) {
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return value.clamp(this._outerPosition.minScrollExtent, this._outerPosition.maxScrollExtent);
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}
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if (value < source.minScrollExtent) {
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return value - source.minScrollExtent + this._outerPosition.minScrollExtent;
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}
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return value - source.minScrollExtent + this._outerPosition.maxScrollExtent;
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}
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public float nestOffset(float value, _NestedScrollPosition target) {
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if (target == this._outerPosition) {
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return value.clamp(this._outerPosition.minScrollExtent, this._outerPosition.maxScrollExtent);
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}
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if (value < this._outerPosition.minScrollExtent) {
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return value - this._outerPosition.minScrollExtent + target.minScrollExtent;
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}
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if (value > this._outerPosition.maxScrollExtent) {
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return value - this._outerPosition.maxScrollExtent + target.minScrollExtent;
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}
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return target.minScrollExtent;
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}
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public void updateCanDrag() {
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if (!this._outerPosition.haveDimensions) {
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return;
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}
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float maxInnerExtent = 0.0f;
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foreach (_NestedScrollPosition position in this._innerPositions) {
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if (!position.haveDimensions) {
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return;
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}
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maxInnerExtent = Mathf.Max(maxInnerExtent, position.maxScrollExtent - position.minScrollExtent);
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}
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this._outerPosition.updateCanDrag(maxInnerExtent);
|
|
}
|
|
|
|
public IPromise animateTo(float to,
|
|
TimeSpan duration,
|
|
Curve curve
|
|
) {
|
|
DrivenScrollActivity outerActivity = this._outerPosition.createDrivenScrollActivity(
|
|
this.nestOffset(to, this._outerPosition),
|
|
duration,
|
|
curve
|
|
);
|
|
List<IPromise> resultFutures = new List<IPromise> {outerActivity.done};
|
|
this.beginActivity(
|
|
outerActivity,
|
|
(_NestedScrollPosition position) => {
|
|
DrivenScrollActivity innerActivity = position.createDrivenScrollActivity(
|
|
this.nestOffset(to, position),
|
|
duration,
|
|
curve
|
|
);
|
|
resultFutures.Add(innerActivity.done);
|
|
return innerActivity;
|
|
}
|
|
);
|
|
return Promise.All(resultFutures);
|
|
}
|
|
|
|
public void jumpTo(float to) {
|
|
this.goIdle();
|
|
this._outerPosition.localJumpTo(this.nestOffset(to, this._outerPosition));
|
|
foreach (_NestedScrollPosition position in this._innerPositions) {
|
|
position.localJumpTo(this.nestOffset(to, position));
|
|
}
|
|
|
|
this.goBallistic(0.0f);
|
|
}
|
|
|
|
public float setPixels(float newPixels) {
|
|
D.assert(false);
|
|
return 0.0f;
|
|
}
|
|
|
|
public ScrollHoldController hold(VoidCallback holdCancelCallback) {
|
|
this.beginActivity(
|
|
new HoldScrollActivity(del: this._outerPosition, onHoldCanceled: holdCancelCallback),
|
|
(_NestedScrollPosition position) => new HoldScrollActivity(del: position)
|
|
);
|
|
return this;
|
|
}
|
|
|
|
public void cancel() {
|
|
this.goBallistic(0.0f);
|
|
}
|
|
|
|
public Drag drag(DragStartDetails details, VoidCallback dragCancelCallback) {
|
|
ScrollDragController drag = new ScrollDragController(
|
|
del: this,
|
|
details: details,
|
|
onDragCanceled: dragCancelCallback
|
|
);
|
|
this.beginActivity(
|
|
new DragScrollActivity(this._outerPosition, drag),
|
|
(_NestedScrollPosition position) => new DragScrollActivity(position, drag)
|
|
);
|
|
D.assert(this._currentDrag == null);
|
|
this._currentDrag = drag;
|
|
return drag;
|
|
}
|
|
|
|
public void applyUserOffset(float delta) {
|
|
this.updateUserScrollDirection(delta > 0.0f ? ScrollDirection.forward : ScrollDirection.reverse);
|
|
D.assert(delta != 0.0f);
|
|
if (!this._innerPositions.Any()) {
|
|
this._outerPosition.applyFullDragUpdate(delta);
|
|
}
|
|
else if (delta < 0.0f) {
|
|
float innerDelta = this._outerPosition.applyClampedDragUpdate(delta);
|
|
if (innerDelta != 0.0f) {
|
|
foreach (_NestedScrollPosition position in this._innerPositions) {
|
|
position.applyFullDragUpdate(innerDelta);
|
|
}
|
|
}
|
|
}
|
|
else {
|
|
float outerDelta = 0.0f; // it will go positive if it changes
|
|
List<float> overscrolls = new List<float> { };
|
|
List<_NestedScrollPosition> innerPositions = this._innerPositions.ToList();
|
|
foreach (_NestedScrollPosition position in innerPositions) {
|
|
float overscroll = position.applyClampedDragUpdate(delta);
|
|
outerDelta = Mathf.Max(outerDelta, overscroll);
|
|
overscrolls.Add(overscroll);
|
|
}
|
|
|
|
if (outerDelta != 0.0f) {
|
|
outerDelta -= this._outerPosition.applyClampedDragUpdate(outerDelta);
|
|
}
|
|
|
|
for (int i = 0; i < innerPositions.Count; ++i) {
|
|
float remainingDelta = overscrolls[i] - outerDelta;
|
|
if (remainingDelta > 0.0f) {
|
|
innerPositions[i].applyFullDragUpdate(remainingDelta);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
public void applyUserScrollOffset(float delta) {
|
|
// TODO: replace with real implementation
|
|
this.applyUserOffset(delta);
|
|
}
|
|
|
|
public void setParent(ScrollController value) {
|
|
this._parent = value;
|
|
this.updateParent();
|
|
}
|
|
|
|
public void updateParent() {
|
|
this._outerPosition?.setParent(this._parent ?? PrimaryScrollController.of(this._state.context));
|
|
}
|
|
|
|
public void dispose() {
|
|
this._currentDrag?.dispose();
|
|
this._currentDrag = null;
|
|
this._outerController.dispose();
|
|
this._innerController.dispose();
|
|
}
|
|
|
|
public override string ToString() {
|
|
return "$GetType()(outer=$_outerController; inner=$_innerController)";
|
|
}
|
|
}
|
|
|
|
class _NestedScrollController : ScrollController {
|
|
public _NestedScrollController(
|
|
_NestedScrollCoordinator coordinator,
|
|
float initialScrollOffset = 0.0f,
|
|
string debugLabel = null
|
|
) : base(initialScrollOffset: initialScrollOffset, debugLabel: debugLabel) {
|
|
this.coordinator = coordinator;
|
|
}
|
|
|
|
public readonly _NestedScrollCoordinator coordinator;
|
|
|
|
public override ScrollPosition createScrollPosition(
|
|
ScrollPhysics physics,
|
|
ScrollContext context,
|
|
ScrollPosition oldPosition
|
|
) {
|
|
return new _NestedScrollPosition(
|
|
coordinator: this.coordinator,
|
|
physics: physics,
|
|
context: context,
|
|
initialPixels: this.initialScrollOffset,
|
|
oldPosition: oldPosition,
|
|
debugLabel: this.debugLabel
|
|
);
|
|
}
|
|
|
|
public override void attach(ScrollPosition position) {
|
|
D.assert(position is _NestedScrollPosition);
|
|
base.attach(position);
|
|
this.coordinator.updateParent();
|
|
this.coordinator.updateCanDrag();
|
|
position.addListener(this._scheduleUpdateShadow);
|
|
this._scheduleUpdateShadow();
|
|
}
|
|
|
|
public override void detach(ScrollPosition position) {
|
|
D.assert(position is _NestedScrollPosition);
|
|
position.removeListener(this._scheduleUpdateShadow);
|
|
base.detach(position);
|
|
this._scheduleUpdateShadow();
|
|
}
|
|
|
|
void _scheduleUpdateShadow() {
|
|
SchedulerBinding.instance.addPostFrameCallback(
|
|
(TimeSpan timeStamp) => { this.coordinator.updateShadow(); }
|
|
);
|
|
}
|
|
|
|
public IEnumerable<_NestedScrollPosition> nestedPositions {
|
|
get {
|
|
foreach (var scrollPosition in this.positions) {
|
|
yield return (_NestedScrollPosition) scrollPosition;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
class _NestedScrollPosition : ScrollPosition, ScrollActivityDelegate {
|
|
public _NestedScrollPosition(
|
|
ScrollPhysics physics,
|
|
ScrollContext context,
|
|
float initialPixels = 0.0f,
|
|
ScrollPosition oldPosition = null,
|
|
string debugLabel = null,
|
|
_NestedScrollCoordinator coordinator = null
|
|
) : base(
|
|
physics: physics,
|
|
context: context,
|
|
oldPosition: oldPosition,
|
|
debugLabel: debugLabel,
|
|
coordinator: coordinator
|
|
) {
|
|
D.assert(coordinator != null);
|
|
if (!this.havePixels) {
|
|
this.correctPixels(initialPixels);
|
|
}
|
|
|
|
if (this.activity == null) {
|
|
this.goIdle();
|
|
}
|
|
|
|
D.assert(this.activity != null);
|
|
this.saveScrollOffset(); // in case we didn't restore but could, so that we don't restore it later
|
|
}
|
|
|
|
public _NestedScrollCoordinator coordinator {
|
|
get { return (_NestedScrollCoordinator) this._coordinator; }
|
|
}
|
|
|
|
public TickerProvider vsync {
|
|
get { return this.context.vsync; }
|
|
}
|
|
|
|
ScrollController _parent;
|
|
|
|
public void setParent(ScrollController value) {
|
|
this._parent?.detach(this);
|
|
this._parent = value;
|
|
this._parent?.attach(this);
|
|
}
|
|
|
|
public override AxisDirection axisDirection {
|
|
get { return this.context.axisDirection; }
|
|
}
|
|
|
|
protected override void absorb(ScrollPosition other) {
|
|
base.absorb(other);
|
|
this.activity.updateDelegate(this);
|
|
}
|
|
|
|
protected override void restoreScrollOffset() {
|
|
if (this.coordinator.canScrollBody) {
|
|
base.restoreScrollOffset();
|
|
}
|
|
}
|
|
|
|
public float applyClampedDragUpdate(float delta) {
|
|
D.assert(delta != 0.0f);
|
|
float min = delta < 0.0f ? -float.PositiveInfinity : Mathf.Min(this.minScrollExtent, this.pixels);
|
|
float max = delta > 0.0f ? float.PositiveInfinity : Mathf.Max(this.maxScrollExtent, this.pixels);
|
|
float oldPixels = this.pixels;
|
|
float newPixels = (this.pixels - delta).clamp(min, max);
|
|
float clampedDelta = newPixels - this.pixels;
|
|
if (clampedDelta == 0.0f) {
|
|
return delta;
|
|
}
|
|
|
|
float overscroll = this.physics.applyBoundaryConditions(this, newPixels);
|
|
float actualNewPixels = newPixels - overscroll;
|
|
float offset = actualNewPixels - oldPixels;
|
|
if (offset != 0.0f) {
|
|
this.forcePixels(actualNewPixels);
|
|
this.didUpdateScrollPositionBy(offset);
|
|
}
|
|
|
|
return delta + offset;
|
|
}
|
|
|
|
public float applyFullDragUpdate(float delta) {
|
|
D.assert(delta != 0.0f);
|
|
float oldPixels = this.pixels;
|
|
float newPixels = this.pixels - this.physics.applyPhysicsToUserOffset(this, delta);
|
|
if (oldPixels == newPixels) {
|
|
return 0.0f; // delta must have been so small we dropped it during floating point addition
|
|
}
|
|
|
|
float overscroll = this.physics.applyBoundaryConditions(this, newPixels);
|
|
float actualNewPixels = newPixels - overscroll;
|
|
if (actualNewPixels != oldPixels) {
|
|
this.forcePixels(actualNewPixels);
|
|
this.didUpdateScrollPositionBy(actualNewPixels - oldPixels);
|
|
}
|
|
|
|
if (overscroll != 0.0f) {
|
|
this.didOverscrollBy(overscroll);
|
|
return overscroll;
|
|
}
|
|
|
|
return 0.0f;
|
|
}
|
|
|
|
public override ScrollDirection userScrollDirection {
|
|
get { return this.coordinator.userScrollDirection; }
|
|
}
|
|
|
|
public DrivenScrollActivity createDrivenScrollActivity(float to, TimeSpan duration, Curve curve) {
|
|
return new DrivenScrollActivity(
|
|
this,
|
|
from: this.pixels,
|
|
to: to,
|
|
duration: duration,
|
|
curve: curve,
|
|
vsync: this.vsync
|
|
);
|
|
}
|
|
|
|
public void applyUserOffset(float delta) {
|
|
D.assert(false);
|
|
}
|
|
|
|
public void applyUserScrollOffset(float delta) {
|
|
// TODO: replace with real implementation
|
|
this.applyUserOffset(delta);
|
|
}
|
|
|
|
public void goIdle() {
|
|
this.beginActivity(new IdleScrollActivity(this));
|
|
}
|
|
|
|
public void goBallistic(float velocity) {
|
|
Simulation simulation = null;
|
|
if (velocity != 0.0f || this.outOfRange()) {
|
|
simulation = this.physics.createBallisticSimulation(this, velocity);
|
|
}
|
|
|
|
this.beginActivity(this.createBallisticScrollActivity(
|
|
simulation,
|
|
mode: _NestedBallisticScrollActivityMode.independent
|
|
));
|
|
}
|
|
|
|
public ScrollActivity createBallisticScrollActivity(
|
|
Simulation simulation = null,
|
|
_NestedBallisticScrollActivityMode? mode = null,
|
|
_NestedScrollMetrics metrics = null
|
|
) {
|
|
if (simulation == null) {
|
|
return new IdleScrollActivity(this);
|
|
}
|
|
|
|
D.assert(mode != null);
|
|
switch (mode) {
|
|
case _NestedBallisticScrollActivityMode.outer:
|
|
D.assert(metrics != null);
|
|
if (metrics.minRange == metrics.maxRange) {
|
|
return new IdleScrollActivity(this);
|
|
}
|
|
|
|
return new _NestedOuterBallisticScrollActivity(this.coordinator, this, metrics, simulation,
|
|
this.context.vsync);
|
|
case _NestedBallisticScrollActivityMode.inner:
|
|
return new _NestedInnerBallisticScrollActivity(this.coordinator, this, simulation,
|
|
this.context.vsync);
|
|
case _NestedBallisticScrollActivityMode.independent:
|
|
return new BallisticScrollActivity(this, simulation, this.context.vsync);
|
|
}
|
|
|
|
return null;
|
|
}
|
|
|
|
public override IPromise animateTo(float to,
|
|
TimeSpan duration,
|
|
Curve curve
|
|
) {
|
|
return this.coordinator.animateTo(this.coordinator.unnestOffset(to, this), duration: duration,
|
|
curve: curve);
|
|
}
|
|
|
|
public override void jumpTo(float value) {
|
|
this.coordinator.jumpTo(this.coordinator.unnestOffset(value, this));
|
|
}
|
|
|
|
public void localJumpTo(float value) {
|
|
if (this.pixels != value) {
|
|
float oldPixels = this.pixels;
|
|
this.forcePixels(value);
|
|
this.didStartScroll();
|
|
this.didUpdateScrollPositionBy(this.pixels - oldPixels);
|
|
this.didEndScroll();
|
|
}
|
|
}
|
|
|
|
protected override void applyNewDimensions() {
|
|
base.applyNewDimensions();
|
|
this.coordinator.updateCanDrag();
|
|
}
|
|
|
|
public void updateCanDrag(float totalExtent) {
|
|
this.context.setCanDrag(totalExtent > (this.viewportDimension - this.maxScrollExtent) ||
|
|
this.minScrollExtent != this.maxScrollExtent);
|
|
}
|
|
|
|
public override ScrollHoldController hold(VoidCallback holdCancelCallback) {
|
|
return this.coordinator.hold(holdCancelCallback);
|
|
}
|
|
|
|
public override Drag drag(DragStartDetails details, VoidCallback dragCancelCallback) {
|
|
return this.coordinator.drag(details, dragCancelCallback);
|
|
}
|
|
|
|
public override void dispose() {
|
|
this._parent?.detach(this);
|
|
base.dispose();
|
|
}
|
|
}
|
|
|
|
enum _NestedBallisticScrollActivityMode {
|
|
outer,
|
|
inner,
|
|
independent
|
|
}
|
|
|
|
class _NestedInnerBallisticScrollActivity : BallisticScrollActivity {
|
|
public _NestedInnerBallisticScrollActivity(
|
|
_NestedScrollCoordinator coordinator,
|
|
_NestedScrollPosition position,
|
|
Simulation simulation,
|
|
TickerProvider vsync
|
|
) : base(position, simulation, vsync) {
|
|
this.coordinator = coordinator;
|
|
}
|
|
|
|
public readonly _NestedScrollCoordinator coordinator;
|
|
|
|
public new _NestedScrollPosition del {
|
|
get { return (_NestedScrollPosition) base.del; }
|
|
}
|
|
|
|
public override void resetActivity() {
|
|
this.del.beginActivity(this.coordinator.createInnerBallisticScrollActivity(this.del, this.velocity));
|
|
}
|
|
|
|
public override void applyNewDimensions() {
|
|
this.del.beginActivity(this.coordinator.createInnerBallisticScrollActivity(this.del, this.velocity));
|
|
}
|
|
|
|
protected override bool applyMoveTo(float value) {
|
|
return base.applyMoveTo(this.coordinator.nestOffset(value, this.del));
|
|
}
|
|
}
|
|
|
|
class _NestedOuterBallisticScrollActivity : BallisticScrollActivity {
|
|
public _NestedOuterBallisticScrollActivity(
|
|
_NestedScrollCoordinator coordinator,
|
|
_NestedScrollPosition position,
|
|
_NestedScrollMetrics metrics,
|
|
Simulation simulation,
|
|
TickerProvider vsync
|
|
) : base(position, simulation, vsync) {
|
|
D.assert(metrics.minRange != metrics.maxRange);
|
|
D.assert(metrics.maxRange > metrics.minRange);
|
|
this.coordinator = coordinator;
|
|
this.metrics = metrics;
|
|
}
|
|
|
|
public readonly _NestedScrollCoordinator coordinator;
|
|
public readonly _NestedScrollMetrics metrics;
|
|
|
|
public new _NestedScrollPosition del {
|
|
get { return (_NestedScrollPosition) base.del; }
|
|
}
|
|
|
|
public override void resetActivity() {
|
|
this.del.beginActivity(this.coordinator.createOuterBallisticScrollActivity(this.velocity));
|
|
}
|
|
|
|
public override void applyNewDimensions() {
|
|
this.del.beginActivity(this.coordinator.createOuterBallisticScrollActivity(this.velocity));
|
|
}
|
|
|
|
protected override bool applyMoveTo(float value) {
|
|
bool done = false;
|
|
if (this.velocity > 0.0f) {
|
|
if (value < this.metrics.minRange) {
|
|
return true;
|
|
}
|
|
|
|
if (value > this.metrics.maxRange) {
|
|
value = this.metrics.maxRange;
|
|
done = true;
|
|
}
|
|
}
|
|
else if (this.velocity < 0.0f) {
|
|
if (value > this.metrics.maxRange) {
|
|
return true;
|
|
}
|
|
|
|
if (value < this.metrics.minRange) {
|
|
value = this.metrics.minRange;
|
|
done = true;
|
|
}
|
|
}
|
|
else {
|
|
value = value.clamp(this.metrics.minRange, this.metrics.maxRange);
|
|
done = true;
|
|
}
|
|
|
|
bool result = base.applyMoveTo(value + this.metrics.correctionOffset);
|
|
D.assert(result); // since we tried to pass an in-range value, it shouldn"t ever overflow
|
|
return !done;
|
|
}
|
|
|
|
public override string ToString() {
|
|
return
|
|
$"{this.GetType()}({this.metrics.minRange} .. {this.metrics.maxRange}; correcting by {this.metrics.correctionOffset})";
|
|
}
|
|
}
|
|
|
|
public class SliverOverlapAbsorberHandle : ChangeNotifier {
|
|
internal int _writers = 0;
|
|
|
|
public float layoutExtent {
|
|
get { return this._layoutExtent; }
|
|
}
|
|
|
|
float _layoutExtent;
|
|
|
|
public float scrollExtent {
|
|
get { return this._scrollExtent; }
|
|
}
|
|
|
|
float _scrollExtent;
|
|
|
|
internal void _setExtents(float layoutValue, float scrollValue) {
|
|
D.assert(this._writers == 1,
|
|
() => "Multiple RenderSliverOverlapAbsorbers have been provided the same SliverOverlapAbsorberHandle.");
|
|
this._layoutExtent = layoutValue;
|
|
this._scrollExtent = scrollValue;
|
|
}
|
|
|
|
internal void _markNeedsLayout() {
|
|
this.notifyListeners();
|
|
}
|
|
|
|
public override string ToString() {
|
|
string extra = "";
|
|
switch (this._writers) {
|
|
case 0:
|
|
extra = ", orphan";
|
|
break;
|
|
case 1:
|
|
break;
|
|
default:
|
|
extra = ", $_writers WRITERS ASSIGNED";
|
|
break;
|
|
}
|
|
|
|
return $"{this.GetType()}({this.layoutExtent}{extra})";
|
|
}
|
|
}
|
|
|
|
public class SliverOverlapAbsorber : SingleChildRenderObjectWidget {
|
|
public SliverOverlapAbsorber(
|
|
Key key = null,
|
|
SliverOverlapAbsorberHandle handle = null,
|
|
Widget child = null
|
|
) : base(key: key, child: child) {
|
|
D.assert(handle != null);
|
|
this.handle = handle;
|
|
}
|
|
|
|
public readonly SliverOverlapAbsorberHandle handle;
|
|
|
|
public override RenderObject createRenderObject(BuildContext context) {
|
|
return new RenderSliverOverlapAbsorber(
|
|
handle: this.handle
|
|
);
|
|
}
|
|
|
|
public override void updateRenderObject(BuildContext context, RenderObject _renderObject) {
|
|
RenderSliverOverlapAbsorber renderObject = _renderObject as RenderSliverOverlapAbsorber;
|
|
renderObject.handle = this.handle;
|
|
}
|
|
|
|
public override void debugFillProperties(DiagnosticPropertiesBuilder properties) {
|
|
base.debugFillProperties(properties);
|
|
properties.add(new DiagnosticsProperty<SliverOverlapAbsorberHandle>("handle", this.handle));
|
|
}
|
|
}
|
|
|
|
public class RenderSliverOverlapAbsorber : RenderObjectWithChildMixinRenderSliver<RenderSliver> {
|
|
public RenderSliverOverlapAbsorber(
|
|
SliverOverlapAbsorberHandle handle,
|
|
RenderSliver child = null
|
|
) {
|
|
D.assert(handle != null);
|
|
this._handle = handle;
|
|
this.child = child;
|
|
}
|
|
|
|
public SliverOverlapAbsorberHandle handle {
|
|
get { return this._handle; }
|
|
set {
|
|
D.assert(value != null);
|
|
if (this.handle == value) {
|
|
return;
|
|
}
|
|
|
|
if (this.attached) {
|
|
this.handle._writers -= 1;
|
|
value._writers += 1;
|
|
value._setExtents(this.handle.layoutExtent, this.handle.scrollExtent);
|
|
}
|
|
|
|
this._handle = value;
|
|
}
|
|
}
|
|
|
|
SliverOverlapAbsorberHandle _handle;
|
|
|
|
public override void attach(object owner) {
|
|
base.attach(owner);
|
|
this.handle._writers += 1;
|
|
}
|
|
|
|
public override void detach() {
|
|
this.handle._writers -= 1;
|
|
base.detach();
|
|
}
|
|
|
|
protected override void performLayout() {
|
|
D.assert(this.handle._writers == 1,
|
|
() =>
|
|
"A SliverOverlapAbsorberHandle cannot be passed to multiple RenderSliverOverlapAbsorber objects at the same time.");
|
|
if (this.child == null) {
|
|
this.geometry = new SliverGeometry();
|
|
return;
|
|
}
|
|
|
|
this.child.layout(this.constraints, parentUsesSize: true);
|
|
SliverGeometry childLayoutGeometry = this.child.geometry;
|
|
this.geometry = new SliverGeometry(
|
|
scrollExtent: childLayoutGeometry.scrollExtent - childLayoutGeometry.maxScrollObstructionExtent,
|
|
paintExtent: childLayoutGeometry.paintExtent,
|
|
paintOrigin: childLayoutGeometry.paintOrigin,
|
|
layoutExtent: childLayoutGeometry.paintExtent - childLayoutGeometry.maxScrollObstructionExtent,
|
|
maxPaintExtent: childLayoutGeometry.maxPaintExtent,
|
|
maxScrollObstructionExtent: childLayoutGeometry.maxScrollObstructionExtent,
|
|
hitTestExtent: childLayoutGeometry.hitTestExtent,
|
|
visible: childLayoutGeometry.visible,
|
|
hasVisualOverflow: childLayoutGeometry.hasVisualOverflow,
|
|
scrollOffsetCorrection: childLayoutGeometry.scrollOffsetCorrection
|
|
);
|
|
this.handle._setExtents(childLayoutGeometry.maxScrollObstructionExtent,
|
|
childLayoutGeometry.maxScrollObstructionExtent);
|
|
}
|
|
|
|
public override void applyPaintTransform(RenderObject child, Matrix3 transform) {
|
|
}
|
|
|
|
protected override bool hitTestChildren(
|
|
HitTestResult result,
|
|
float mainAxisPosition = 0,
|
|
float crossAxisPosition = 0
|
|
) {
|
|
if (this.child != null) {
|
|
return this.child.hitTest(result, mainAxisPosition: mainAxisPosition,
|
|
crossAxisPosition: crossAxisPosition);
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
public override void paint(PaintingContext context, Offset offset) {
|
|
if (this.child != null) {
|
|
context.paintChild(this.child, offset);
|
|
}
|
|
}
|
|
|
|
public override void debugFillProperties(DiagnosticPropertiesBuilder properties) {
|
|
base.debugFillProperties(properties);
|
|
properties.add(new DiagnosticsProperty<SliverOverlapAbsorberHandle>("handle", this.handle));
|
|
}
|
|
}
|
|
|
|
public class SliverOverlapInjector : SingleChildRenderObjectWidget {
|
|
public SliverOverlapInjector(
|
|
Key key = null,
|
|
SliverOverlapAbsorberHandle handle = null,
|
|
Widget child = null
|
|
) : base(key: key, child: child) {
|
|
D.assert(handle != null);
|
|
this.handle = handle;
|
|
}
|
|
|
|
public readonly SliverOverlapAbsorberHandle handle;
|
|
|
|
public override RenderObject createRenderObject(BuildContext context) {
|
|
return new RenderSliverOverlapInjector(
|
|
handle: this.handle
|
|
);
|
|
}
|
|
|
|
public override void updateRenderObject(BuildContext context, RenderObject _renderObject) {
|
|
RenderSliverOverlapInjector renderObject = _renderObject as RenderSliverOverlapInjector;
|
|
renderObject.handle = this.handle;
|
|
}
|
|
|
|
public override void debugFillProperties(DiagnosticPropertiesBuilder properties) {
|
|
base.debugFillProperties(properties);
|
|
properties.add(new DiagnosticsProperty<SliverOverlapAbsorberHandle>("handle", this.handle));
|
|
}
|
|
}
|
|
|
|
public class RenderSliverOverlapInjector : RenderSliver {
|
|
public RenderSliverOverlapInjector(
|
|
SliverOverlapAbsorberHandle handle
|
|
) {
|
|
D.assert(handle != null);
|
|
this._handle = handle;
|
|
}
|
|
|
|
float _currentLayoutExtent;
|
|
float _currentMaxExtent;
|
|
|
|
public SliverOverlapAbsorberHandle handle {
|
|
get { return this._handle; }
|
|
set {
|
|
D.assert(value != null);
|
|
if (this.handle == value) {
|
|
return;
|
|
}
|
|
|
|
if (this.attached) {
|
|
this.handle.removeListener(this.markNeedsLayout);
|
|
}
|
|
|
|
this._handle = value;
|
|
if (this.attached) {
|
|
this.handle.addListener(this.markNeedsLayout);
|
|
if (this.handle.layoutExtent != this._currentLayoutExtent ||
|
|
this.handle.scrollExtent != this._currentMaxExtent) {
|
|
this.markNeedsLayout();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
SliverOverlapAbsorberHandle _handle;
|
|
|
|
public override void attach(object owner) {
|
|
base.attach(owner);
|
|
this.handle.addListener(this.markNeedsLayout);
|
|
if (this.handle.layoutExtent != this._currentLayoutExtent ||
|
|
this.handle.scrollExtent != this._currentMaxExtent) {
|
|
this.markNeedsLayout();
|
|
}
|
|
}
|
|
|
|
public override void detach() {
|
|
this.handle.removeListener(this.markNeedsLayout);
|
|
base.detach();
|
|
}
|
|
|
|
protected override void performLayout() {
|
|
this._currentLayoutExtent = this.handle.layoutExtent;
|
|
this._currentMaxExtent = this.handle.layoutExtent;
|
|
float clampedLayoutExtent = Mathf.Min(this._currentLayoutExtent - this.constraints.scrollOffset,
|
|
this.constraints.remainingPaintExtent);
|
|
this.geometry = new SliverGeometry(
|
|
scrollExtent: this._currentLayoutExtent,
|
|
paintExtent: Mathf.Max(0.0f, clampedLayoutExtent),
|
|
maxPaintExtent: this._currentMaxExtent
|
|
);
|
|
}
|
|
|
|
public override void debugPaint(PaintingContext context, Offset offset) {
|
|
D.assert(() => {
|
|
if (D.debugPaintSizeEnabled) {
|
|
Paint paint = new Paint();
|
|
paint.color = new Color(0xFFCC9933);
|
|
paint.strokeWidth = 3.0f;
|
|
paint.style = PaintingStyle.stroke;
|
|
Offset start, end, delta;
|
|
switch (this.constraints.axis) {
|
|
case Axis.vertical:
|
|
float x = offset.dx + this.constraints.crossAxisExtent / 2.0f;
|
|
start = new Offset(x, offset.dy);
|
|
end = new Offset(x, offset.dy + this.geometry.paintExtent);
|
|
delta = new Offset(this.constraints.crossAxisExtent / 5.0f, 0.0f);
|
|
break;
|
|
case Axis.horizontal:
|
|
float y = offset.dy + this.constraints.crossAxisExtent / 2.0f;
|
|
start = new Offset(offset.dx, y);
|
|
end = new Offset(offset.dy + this.geometry.paintExtent, y);
|
|
delta = new Offset(0.0f, this.constraints.crossAxisExtent / 5.0f);
|
|
break;
|
|
default:
|
|
throw new Exception("");
|
|
}
|
|
|
|
for (int index = -2; index <= 2; index += 1) {
|
|
PaintingUtilities.paintZigZag(context.canvas, paint, start - delta * (float) index,
|
|
end - delta * (float) index, 10, 10.0f);
|
|
}
|
|
}
|
|
|
|
return true;
|
|
});
|
|
}
|
|
|
|
public override void debugFillProperties(DiagnosticPropertiesBuilder properties) {
|
|
base.debugFillProperties(properties);
|
|
properties.add(new DiagnosticsProperty<SliverOverlapAbsorberHandle>("handle", this.handle));
|
|
}
|
|
}
|
|
|
|
public class NestedScrollViewViewport : Viewport {
|
|
public NestedScrollViewViewport(
|
|
Key key = null,
|
|
AxisDirection axisDirection = AxisDirection.down,
|
|
AxisDirection crossAxisDirection = AxisDirection.right,
|
|
float anchor = 0.0f,
|
|
ViewportOffset offset = null,
|
|
Key center = null,
|
|
List<Widget> slivers = null,
|
|
SliverOverlapAbsorberHandle handle = null
|
|
) : base(
|
|
key: key,
|
|
axisDirection: axisDirection,
|
|
crossAxisDirection: crossAxisDirection,
|
|
anchor: anchor,
|
|
offset: offset,
|
|
center: center,
|
|
slivers: slivers ?? new List<Widget>()
|
|
) {
|
|
D.assert(handle != null);
|
|
D.assert(this.offset != null);
|
|
this.handle = handle;
|
|
}
|
|
|
|
public readonly SliverOverlapAbsorberHandle handle;
|
|
|
|
public override RenderObject createRenderObject(BuildContext context) {
|
|
return new RenderNestedScrollViewViewport(
|
|
axisDirection: this.axisDirection,
|
|
crossAxisDirection: this.crossAxisDirection ??
|
|
getDefaultCrossAxisDirection(context, this.axisDirection),
|
|
anchor: this.anchor,
|
|
offset: this.offset,
|
|
handle: this.handle
|
|
);
|
|
}
|
|
|
|
public override void updateRenderObject(BuildContext context, RenderObject _renderObject) {
|
|
RenderNestedScrollViewViewport renderObject = _renderObject as RenderNestedScrollViewViewport;
|
|
renderObject.axisDirection = this.axisDirection;
|
|
renderObject.crossAxisDirection = this.crossAxisDirection ??
|
|
getDefaultCrossAxisDirection(context, this.axisDirection);
|
|
if (this.crossAxisDirection == null) {
|
|
renderObject.anchor = this.anchor;
|
|
}
|
|
|
|
renderObject.offset = this.offset;
|
|
renderObject.handle = this.handle;
|
|
}
|
|
|
|
public override void debugFillProperties(DiagnosticPropertiesBuilder properties) {
|
|
base.debugFillProperties(properties);
|
|
properties.add(new DiagnosticsProperty<SliverOverlapAbsorberHandle>("handle", this.handle));
|
|
}
|
|
}
|
|
|
|
public class RenderNestedScrollViewViewport : RenderViewport {
|
|
public RenderNestedScrollViewViewport(
|
|
AxisDirection axisDirection = AxisDirection.down,
|
|
AxisDirection crossAxisDirection = AxisDirection.right,
|
|
ViewportOffset offset = null,
|
|
float anchor = 0.0f,
|
|
List<RenderSliver> children = null,
|
|
RenderSliver center = null,
|
|
SliverOverlapAbsorberHandle handle = null
|
|
) : base(
|
|
axisDirection: axisDirection,
|
|
crossAxisDirection: crossAxisDirection,
|
|
offset: offset,
|
|
anchor: anchor,
|
|
children: children,
|
|
center: center
|
|
) {
|
|
D.assert(handle != null);
|
|
D.assert(offset != null);
|
|
this._handle = handle;
|
|
}
|
|
|
|
public SliverOverlapAbsorberHandle handle {
|
|
get { return this._handle; }
|
|
set {
|
|
D.assert(value != null);
|
|
if (this.handle == value) {
|
|
return;
|
|
}
|
|
|
|
this._handle = value;
|
|
this.handle._markNeedsLayout();
|
|
}
|
|
}
|
|
|
|
SliverOverlapAbsorberHandle _handle;
|
|
|
|
public override void markNeedsLayout() {
|
|
this.handle._markNeedsLayout();
|
|
base.markNeedsLayout();
|
|
}
|
|
|
|
public override void debugFillProperties(DiagnosticPropertiesBuilder properties) {
|
|
base.debugFillProperties(properties);
|
|
properties.add(new DiagnosticsProperty<SliverOverlapAbsorberHandle>("handle", this.handle));
|
|
}
|
|
}
|
|
}
|