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827 行
32 KiB
827 行
32 KiB
using System;
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using System.Collections.Generic;
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using System.Linq;
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using System.Runtime.CompilerServices;
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using JetBrains.Annotations;
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using Unity.UIWidgets.animation;
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using Unity.UIWidgets.async2;
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using Unity.UIWidgets.foundation;
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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.external;
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using Unity.UIWidgets.scheduler2;
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using Unity.UIWidgets.ui;
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using UnityEngine;
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namespace Unity.UIWidgets.widgets {
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public interface ListWheelChildDelegate {
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Widget build(BuildContext context, int index);
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int? estimatedChildCount { get; }
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int trueIndexOf(int index);
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bool shouldRebuild(ListWheelChildDelegate oldDelegate);
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}
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public class ListWheelChildListDelegate : ListWheelChildDelegate {
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public ListWheelChildListDelegate(
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List<Widget> children
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) {
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D.assert(children != null);
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this.children = children;
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}
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public readonly List<Widget> children;
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public int? estimatedChildCount {
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get { return children.Count; }
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}
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public Widget build(BuildContext context, int index) {
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if (index < 0 || index >= children.Count) {
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return null;
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}
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return new IndexedSemantics(child: children[index], index: index);
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}
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public int trueIndexOf(int index) {
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return index;
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}
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public bool shouldRebuild(ListWheelChildDelegate oldDelegate) {
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return children != ((ListWheelChildListDelegate) oldDelegate).children;
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}
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}
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public class ListWheelChildLoopingListDelegate : ListWheelChildDelegate {
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public ListWheelChildLoopingListDelegate(
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List<Widget> children
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) {
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D.assert(children != null);
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this.children = children;
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}
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public readonly List<Widget> children;
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public int? estimatedChildCount {
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get { return null; }
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}
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public int trueIndexOf(int index) {
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return index % children.Count;
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}
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public Widget build(BuildContext context, int index) {
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if (children.isEmpty()) {
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return null;
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}
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return new IndexedSemantics(child: children[Mathf.Abs(index % children.Count)]);
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}
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public bool shouldRebuild(ListWheelChildDelegate oldDelegate) {
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return children != ((ListWheelChildLoopingListDelegate) oldDelegate).children;
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}
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}
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public class ListWheelChildBuilderDelegate : ListWheelChildDelegate {
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public ListWheelChildBuilderDelegate(
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IndexedWidgetBuilder builder,
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int? childCount = null
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) {
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D.assert(builder != null);
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this.builder = builder;
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this.childCount = childCount;
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}
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public readonly IndexedWidgetBuilder builder;
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public readonly int? childCount;
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public int? estimatedChildCount {
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get { return childCount; }
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}
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public Widget build(BuildContext context, int index) {
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if (childCount == null) {
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Widget child = builder(context, index);
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return child == null ? null : new IndexedSemantics(child: child);
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}
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if (index < 0 || index >= childCount) {
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return null;
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}
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return new IndexedSemantics(child: builder(context, index));
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}
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public int trueIndexOf(int index) {
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return index;
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}
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public bool shouldRebuild(ListWheelChildDelegate oldDelegate) {
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return builder != ((ListWheelChildBuilderDelegate) oldDelegate).builder ||
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childCount != ((ListWheelChildBuilderDelegate) oldDelegate).childCount;
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}
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}
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class ListWheelScrollViewUtils {
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public static int _getItemFromOffset(
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float offset ,
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float itemExtent ,
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float minScrollExtent ,
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float maxScrollExtent
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) {
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return (_clipOffsetToScrollableRange(offset, minScrollExtent, maxScrollExtent) / itemExtent).round();
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}
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public static float _clipOffsetToScrollableRange(
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float offset,
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float minScrollExtent,
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float maxScrollExtent
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) {
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return Mathf.Min(Mathf.Max(offset, minScrollExtent), maxScrollExtent);
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}
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}
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public class FixedExtentScrollController : ScrollController {
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public FixedExtentScrollController(
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int initialItem = 0
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) {
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this.initialItem = initialItem;
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}
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public readonly int initialItem;
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public int selectedItem {
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get {
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D.assert(positions.isNotEmpty(),
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() =>
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"FixedExtentScrollController.selectedItem cannot be accessed before a scroll view is built with it."
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);
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D.assert(positions.Count == 1,
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() =>
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"The selectedItem property cannot be read when multiple scroll views are attached to the same FixedExtentScrollController."
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);
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_FixedExtentScrollPosition position = (_FixedExtentScrollPosition) this.position;
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return position.itemIndex;
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}
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}
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public Future animateToItem(
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int itemIndex,
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TimeSpan duration,
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Curve curve
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) {
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if (!hasClients) {
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return null;
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}
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List<Future> futures = new List<Future>();
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foreach (_FixedExtentScrollPosition position in positions.Cast<_FixedExtentScrollPosition>()) {
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futures.Add(position.animateTo(
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itemIndex * position.itemExtent,
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duration: duration,
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curve: curve
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));
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}
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return Future.wait<object>(futures);
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}
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public void jumpToItem(int itemIndex) {
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foreach (_FixedExtentScrollPosition position in positions.Cast<_FixedExtentScrollPosition>()) {
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position.jumpTo(itemIndex * position.itemExtent);
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}
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}
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public override ScrollPosition createScrollPosition(
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ScrollPhysics physics,
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ScrollContext context,
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ScrollPosition oldPosition) {
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return new _FixedExtentScrollPosition(
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physics: physics,
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context: context,
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initialItem: initialItem,
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oldPosition: oldPosition
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);
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}
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}
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public interface IFixedExtentMetrics {
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int itemIndex { set; get; }
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FixedExtentMetrics 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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int? itemIndex = null
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);
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}
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public class FixedExtentMetrics : FixedScrollMetrics, IFixedExtentMetrics {
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public FixedExtentMetrics(
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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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int itemIndex
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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.itemIndex = itemIndex;
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}
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public int itemIndex { get; set; }
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public FixedExtentMetrics 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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int? itemIndex = null
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) {
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return new FixedExtentMetrics(
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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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itemIndex: itemIndex ?? this.itemIndex
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);
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}
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}
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class _FixedExtentScrollPosition : ScrollPositionWithSingleContext, IFixedExtentMetrics {
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public _FixedExtentScrollPosition(
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ScrollPhysics physics = null,
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ScrollContext context = null,
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int? initialItem = null,
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bool keepScrollOffset = true,
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ScrollPosition oldPosition = null,
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string debugLabel = null
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) : base(
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physics: physics,
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context: context,
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initialPixels: _getItemExtentFromScrollContext(context) * (initialItem ?? 0.0f),
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keepScrollOffset: keepScrollOffset,
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oldPosition: oldPosition,
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debugLabel: debugLabel
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) {
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D.assert(
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context is _FixedExtentScrollableState,
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() => "FixedExtentScrollController can only be used with ListWheelScrollViews"
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);
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}
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static float _getItemExtentFromScrollContext(ScrollContext context) {
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_FixedExtentScrollableState scrollable = (_FixedExtentScrollableState) context;
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return scrollable.itemExtent;
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}
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public float itemExtent {
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get { return _getItemExtentFromScrollContext(context); }
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}
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public int itemIndex {
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get {
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return ListWheelScrollViewUtils._getItemFromOffset(
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offset: pixels,
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itemExtent: itemExtent,
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minScrollExtent: minScrollExtent,
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maxScrollExtent: maxScrollExtent
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);
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}
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set { }
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}
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public FixedExtentMetrics 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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int? itemIndex = null
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) {
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return new FixedExtentMetrics(
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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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itemIndex: itemIndex ?? this.itemIndex
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);
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}
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}
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class _FixedExtentScrollable : Scrollable {
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public _FixedExtentScrollable(
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float itemExtent,
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Key key = null,
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AxisDirection axisDirection = AxisDirection.down,
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ScrollController controller = null,
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ScrollPhysics physics = null,
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ViewportBuilder viewportBuilder = null
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) : base(
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key: key,
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axisDirection: axisDirection,
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controller: controller,
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physics: physics,
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viewportBuilder: viewportBuilder
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) {
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this.itemExtent = itemExtent;
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}
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public readonly float itemExtent;
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public override State createState() {
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return new _FixedExtentScrollableState();
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}
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}
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class _FixedExtentScrollableState : ScrollableState {
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public float itemExtent {
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get {
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_FixedExtentScrollable actualWidget = (_FixedExtentScrollable) widget;
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return actualWidget.itemExtent;
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}
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}
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}
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public class FixedExtentScrollPhysics : ScrollPhysics {
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public FixedExtentScrollPhysics(
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ScrollPhysics parent = null
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) : base(parent: parent) { }
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public override ScrollPhysics applyTo(ScrollPhysics ancestor) {
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return new FixedExtentScrollPhysics(parent: buildParent(ancestor));
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}
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public override Simulation createBallisticSimulation(ScrollMetrics position, float velocity) {
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D.assert(
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position is _FixedExtentScrollPosition,
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() => "FixedExtentScrollPhysics can only be used with Scrollables that uses " +
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"the FixedExtentScrollController"
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);
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_FixedExtentScrollPosition metrics = (_FixedExtentScrollPosition) position;
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if ((velocity <= 0.0f && metrics.pixels <= metrics.minScrollExtent) ||
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(velocity >= 0.0f && metrics.pixels >= metrics.maxScrollExtent)) {
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return base.createBallisticSimulation(metrics, velocity);
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}
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Simulation testFrictionSimulation =
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base.createBallisticSimulation(metrics, velocity);
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if (testFrictionSimulation != null
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&& (testFrictionSimulation.x(float.PositiveInfinity) == metrics.minScrollExtent
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|| testFrictionSimulation.x(float.PositiveInfinity) == metrics.maxScrollExtent)) {
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return base.createBallisticSimulation(metrics, velocity);
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}
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int settlingItemIndex = ListWheelScrollViewUtils._getItemFromOffset(
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offset: testFrictionSimulation?.x(float.PositiveInfinity) ?? metrics.pixels,
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itemExtent: metrics.itemExtent,
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minScrollExtent: metrics.minScrollExtent,
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maxScrollExtent: metrics.maxScrollExtent
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);
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float settlingPixels = settlingItemIndex * metrics.itemExtent;
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if (velocity.abs() < tolerance.velocity
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&& (settlingPixels - metrics.pixels).abs() < tolerance.distance) {
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return null;
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}
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if (settlingItemIndex == metrics.itemIndex) {
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return new SpringSimulation(
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spring,
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metrics.pixels,
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settlingPixels,
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velocity,
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tolerance: tolerance
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);
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}
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return FrictionSimulation.through(
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metrics.pixels,
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settlingPixels,
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velocity,
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tolerance.velocity * velocity.sign()
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);
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}
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}
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public class ListWheelScrollView : StatefulWidget {
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public ListWheelScrollView(
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List<Widget> children,
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float itemExtent,
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Key key = null,
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ScrollController controller = null,
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ScrollPhysics physics = null,
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float diameterRatio = RenderListWheelViewport.defaultDiameterRatio,
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float perspective = RenderListWheelViewport.defaultPerspective,
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float offAxisFraction = 0.0f,
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bool useMagnifier = false,
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float magnification = 1.0f,
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float overAndUnderCenterOpacity = 1.0f,
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float squeeze = 1.0f,
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ValueChanged<int> onSelectedItemChanged = null,
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bool clipToSize = true,
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bool renderChildrenOutsideViewport = false
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) : base(key: key) {
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//D.assert(children != null);
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D.assert(diameterRatio > 0.0, () => RenderListWheelViewport.diameterRatioZeroMessage);
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D.assert(perspective > 0);
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D.assert(perspective <= 0.01f, () => RenderListWheelViewport.perspectiveTooHighMessage);
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D.assert(magnification > 0);
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D.assert(overAndUnderCenterOpacity >= 0 && overAndUnderCenterOpacity <= 1);
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D.assert(itemExtent > 0);
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D.assert(squeeze > 0);
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D.assert(
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!renderChildrenOutsideViewport || !clipToSize,
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() => RenderListWheelViewport.clipToSizeAndRenderChildrenOutsideViewportConflict
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);
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childDelegate = new ListWheelChildListDelegate(children: children);
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this.overAndUnderCenterOpacity = overAndUnderCenterOpacity;
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this.itemExtent = itemExtent;
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this.squeeze = squeeze;
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this.controller = controller;
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this.physics = physics;
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this.diameterRatio = diameterRatio;
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this.perspective = perspective;
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this.offAxisFraction = offAxisFraction;
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this.useMagnifier = useMagnifier;
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this.magnification = magnification;
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this.onSelectedItemChanged = onSelectedItemChanged;
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this.clipToSize = clipToSize;
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this.renderChildrenOutsideViewport = renderChildrenOutsideViewport;
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}
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public ListWheelScrollView (
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float itemExtent,
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Key key = null,
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ScrollController controller = null,
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ScrollPhysics physics = null,
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float diameterRatio = RenderListWheelViewport.defaultDiameterRatio,
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float perspective = RenderListWheelViewport.defaultPerspective,
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float offAxisFraction = 0.0f,
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bool useMagnifier = false,
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float magnification = 1.0f,
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float squeeze = 1.0f,
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ValueChanged<int> onSelectedItemChanged = null,
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float overAndUnderCenterOpacity = 1.0f,
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bool clipToSize = true,
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bool renderChildrenOutsideViewport = false,
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ListWheelChildDelegate childDelegate = null
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) : base(key: key) {
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D.assert(childDelegate != null);
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D.assert(diameterRatio > 0.0, ()=>RenderListWheelViewport.diameterRatioZeroMessage);
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D.assert(perspective > 0);
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D.assert(perspective <= 0.01,()=> RenderListWheelViewport.perspectiveTooHighMessage);
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D.assert(magnification > 0);
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D.assert(overAndUnderCenterOpacity >= 0 && overAndUnderCenterOpacity <= 1);
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D.assert(itemExtent != null);
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D.assert(itemExtent > 0);
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D.assert(squeeze > 0);
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D.assert(
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!renderChildrenOutsideViewport || !clipToSize,()=>
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RenderListWheelViewport.clipToSizeAndRenderChildrenOutsideViewportConflict
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);
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this.controller = controller;
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this.physics = physics;
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this.diameterRatio = diameterRatio;
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this.perspective = perspective;
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this.offAxisFraction = offAxisFraction;
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this.useMagnifier = useMagnifier;
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this.magnification = magnification;
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this.overAndUnderCenterOpacity = overAndUnderCenterOpacity;
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this.itemExtent = itemExtent;
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this.squeeze = squeeze;
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this.onSelectedItemChanged = onSelectedItemChanged;
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this.clipToSize = clipToSize;
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this.renderChildrenOutsideViewport = renderChildrenOutsideViewport;
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this.childDelegate = childDelegate;
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}
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public readonly ScrollController controller;
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public readonly ScrollPhysics physics;
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public readonly float diameterRatio;
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public readonly float perspective;
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public readonly float offAxisFraction;
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public readonly bool useMagnifier;
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public readonly float magnification;
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public readonly float itemExtent;
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public readonly float overAndUnderCenterOpacity;
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public readonly float squeeze;
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public readonly ValueChanged<int> onSelectedItemChanged;
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public readonly bool clipToSize;
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public readonly bool renderChildrenOutsideViewport;
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public ListWheelChildDelegate childDelegate;
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public override State createState() {
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return new _ListWheelScrollViewState();
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}
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}
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class _ListWheelScrollViewState : State<ListWheelScrollView> {
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int _lastReportedItemIndex = 0;
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ScrollController scrollController;
|
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|
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public override void initState() {
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base.initState();
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scrollController = widget.controller ?? new FixedExtentScrollController();
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if (widget.controller is FixedExtentScrollController controller) {
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_lastReportedItemIndex = controller.initialItem;
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}
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}
|
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|
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public override void didUpdateWidget(StatefulWidget oldWidget) {
|
|
base.didUpdateWidget(oldWidget);
|
|
if (widget.controller != null && widget.controller != scrollController) {
|
|
ScrollController oldScrollController = scrollController;
|
|
SchedulerBinding.instance.addPostFrameCallback((_) => { oldScrollController.dispose(); });
|
|
scrollController = widget.controller;
|
|
}
|
|
}
|
|
|
|
public override Widget build(BuildContext context) {
|
|
return new NotificationListener<ScrollNotification>(
|
|
onNotification: (ScrollNotification notification) => {
|
|
if (notification.depth == 0
|
|
&& widget.onSelectedItemChanged != null
|
|
&& notification is ScrollUpdateNotification
|
|
&& notification.metrics is FixedExtentMetrics metrics) {
|
|
int currentItemIndex = metrics.itemIndex;
|
|
if (currentItemIndex != _lastReportedItemIndex) {
|
|
_lastReportedItemIndex = currentItemIndex;
|
|
int trueIndex = widget.childDelegate.trueIndexOf(currentItemIndex);
|
|
widget.onSelectedItemChanged(trueIndex);
|
|
}
|
|
}
|
|
|
|
return false;
|
|
},
|
|
child: new _FixedExtentScrollable(
|
|
controller: scrollController,
|
|
physics: widget.physics,
|
|
itemExtent: widget.itemExtent,
|
|
viewportBuilder: (BuildContext _context, ViewportOffset _offset) => {
|
|
return new ListWheelViewport(
|
|
diameterRatio: widget.diameterRatio,
|
|
perspective: widget.perspective,
|
|
offAxisFraction: widget.offAxisFraction,
|
|
useMagnifier: widget.useMagnifier,
|
|
magnification: widget.magnification,
|
|
overAndUnderCenterOpacity: widget.overAndUnderCenterOpacity,
|
|
itemExtent: widget.itemExtent ,
|
|
squeeze: widget.squeeze,
|
|
clipToSize: widget.clipToSize,
|
|
renderChildrenOutsideViewport: widget.renderChildrenOutsideViewport,
|
|
offset: _offset,
|
|
childDelegate: widget.childDelegate
|
|
);
|
|
}
|
|
)
|
|
);
|
|
}
|
|
}
|
|
|
|
public class ListWheelElement : RenderObjectElement, IListWheelChildManager {
|
|
public ListWheelElement(ListWheelViewport widget) : base(widget) { }
|
|
|
|
public new ListWheelViewport widget {
|
|
get { return (ListWheelViewport) base.widget; }
|
|
}
|
|
|
|
public new RenderListWheelViewport renderObject {
|
|
get { return (RenderListWheelViewport)base.renderObject; }
|
|
}
|
|
|
|
|
|
readonly Dictionary<int, Widget> _childWidgets = new Dictionary<int, Widget>();
|
|
|
|
readonly SplayTree<int, Element> _childElements = new SplayTree<int, Element>();
|
|
|
|
public override void update(Widget newWidget) {
|
|
ListWheelViewport oldWidget = widget;
|
|
base.update(newWidget);
|
|
ListWheelChildDelegate newDelegate = ((ListWheelViewport) newWidget).childDelegate;
|
|
ListWheelChildDelegate oldDelegate = oldWidget.childDelegate;
|
|
if (newDelegate != oldDelegate &&
|
|
(newDelegate.GetType() != oldDelegate.GetType() || newDelegate.shouldRebuild(oldDelegate))) {
|
|
performRebuild();
|
|
}
|
|
}
|
|
|
|
public int? childCount {
|
|
get { return widget.childDelegate.estimatedChildCount; }
|
|
}
|
|
|
|
protected override void performRebuild() {
|
|
_childWidgets.Clear();
|
|
base.performRebuild();
|
|
if (_childElements.isEmpty()) {
|
|
return;
|
|
}
|
|
|
|
int firstIndex = _childElements.First()?.Key ?? 0;
|
|
int lastIndex = _childElements.Last()?.Key ?? _childElements.Count;
|
|
|
|
for (int index = firstIndex; index <= lastIndex; ++index) {
|
|
Element newChild = updateChild(_childElements[index], retrieveWidget(index), index);
|
|
if (newChild != null) {
|
|
_childElements[index] = newChild;
|
|
}
|
|
else {
|
|
_childElements.Remove(index);
|
|
}
|
|
}
|
|
}
|
|
|
|
Widget retrieveWidget(int index) {
|
|
return _childWidgets.putIfAbsent(index,
|
|
() => { return widget.childDelegate.build(this, index); });
|
|
}
|
|
|
|
public bool childExistsAt(int index) {
|
|
return retrieveWidget(index) != null;
|
|
}
|
|
|
|
public void createChild(int index, RenderBox after) {
|
|
owner.buildScope(this, () => {
|
|
bool insertFirst = after == null;
|
|
D.assert(insertFirst || _childElements.getOrDefault(index - 1) != null);
|
|
Element newChild = updateChild(_childElements.getOrDefault(index), retrieveWidget(index), index);
|
|
if (newChild != null) {
|
|
_childElements[index] = newChild;
|
|
}
|
|
else {
|
|
_childElements.Remove(index);
|
|
}
|
|
});
|
|
}
|
|
|
|
public void removeChild(RenderBox child) {
|
|
int index = renderObject.indexOf(child);
|
|
owner.buildScope(this, () => {
|
|
D.assert(_childElements.ContainsKey(index));
|
|
Element result = updateChild(_childElements[index], null, index);
|
|
D.assert(result == null);
|
|
_childElements.Remove(index);
|
|
D.assert(!_childElements.ContainsKey(index));
|
|
});
|
|
}
|
|
|
|
protected override Element updateChild(Element child, Widget newWidget, object newSlot) {
|
|
ListWheelParentData oldParentData = (ListWheelParentData) child?.renderObject?.parentData;
|
|
Element newChild = base.updateChild(child, newWidget, newSlot);
|
|
ListWheelParentData newParentData = (ListWheelParentData) newChild?.renderObject?.parentData;
|
|
if (newParentData != null) {
|
|
newParentData.index = (int) newSlot;
|
|
if (oldParentData != null) {
|
|
newParentData.offset = oldParentData.offset;
|
|
}
|
|
}
|
|
|
|
return newChild;
|
|
}
|
|
|
|
protected override void insertChildRenderObject(RenderObject child, object slot) {
|
|
RenderListWheelViewport renderObject = this.renderObject;
|
|
D.assert(renderObject.debugValidateChild(child));
|
|
int slotNum = (int) slot;
|
|
renderObject.insert(child as RenderBox, after: _childElements.getOrDefault(slotNum - 1)?.renderObject as RenderBox);
|
|
D.assert(renderObject == this.renderObject);
|
|
}
|
|
|
|
protected override void moveChildRenderObject(RenderObject child, dynamic slot) {
|
|
string moveChildRenderObjectErrorMessage =
|
|
"Currently we maintain the list in contiguous increasing order, so " +
|
|
"moving children around is not allowed.";
|
|
D.assert(false, () => moveChildRenderObjectErrorMessage);
|
|
}
|
|
|
|
protected override void removeChildRenderObject(RenderObject child) {
|
|
D.assert(child.parent == renderObject);
|
|
renderObject.remove((RenderBox) child);
|
|
}
|
|
|
|
public override void visitChildren(ElementVisitor visitor) {
|
|
foreach (var item in _childElements) {
|
|
visitor(item.Value);
|
|
}
|
|
}
|
|
|
|
internal override void forgetChild(Element child) {
|
|
_childElements.Remove((int) (child.slot));
|
|
base.forgetChild(child);
|
|
}
|
|
}
|
|
|
|
public class ListWheelViewport : RenderObjectWidget {
|
|
public ListWheelViewport(
|
|
Key key = null,
|
|
float diameterRatio = RenderListWheelViewport.defaultDiameterRatio,
|
|
float perspective = RenderListWheelViewport.defaultPerspective,
|
|
float offAxisFraction = 0.0f,
|
|
bool useMagnifier = false,
|
|
float magnification = 1.0f,
|
|
float overAndUnderCenterOpacity = 1.0f,
|
|
float? itemExtent = null,
|
|
float squeeze = 1.0f,
|
|
bool clipToSize = true,
|
|
bool renderChildrenOutsideViewport = false,
|
|
ViewportOffset offset = null,
|
|
ListWheelChildDelegate childDelegate = null
|
|
) : base(key: key) {
|
|
D.assert(childDelegate != null);
|
|
D.assert(offset != null);
|
|
D.assert(diameterRatio > 0, () => RenderListWheelViewport.diameterRatioZeroMessage);
|
|
D.assert(perspective > 0);
|
|
D.assert(perspective <= 0.01, () => RenderListWheelViewport.perspectiveTooHighMessage);
|
|
D.assert(overAndUnderCenterOpacity >= 0 && overAndUnderCenterOpacity <= 1);
|
|
D.assert(itemExtent != null);
|
|
D.assert(itemExtent > 0);
|
|
D.assert(
|
|
!renderChildrenOutsideViewport || !clipToSize,
|
|
() => RenderListWheelViewport.clipToSizeAndRenderChildrenOutsideViewportConflict
|
|
);
|
|
this.diameterRatio = diameterRatio;
|
|
this.perspective = perspective;
|
|
this.offAxisFraction = offAxisFraction;
|
|
this.useMagnifier = useMagnifier;
|
|
this.magnification = magnification;
|
|
this.overAndUnderCenterOpacity = overAndUnderCenterOpacity;
|
|
this.itemExtent = itemExtent;
|
|
this.squeeze = squeeze;
|
|
this.clipToSize = clipToSize;
|
|
this.renderChildrenOutsideViewport = renderChildrenOutsideViewport;
|
|
this.offset = offset;
|
|
this.childDelegate = childDelegate;
|
|
}
|
|
|
|
public readonly float diameterRatio;
|
|
public readonly float perspective;
|
|
public readonly float offAxisFraction;
|
|
public readonly bool useMagnifier;
|
|
public readonly float magnification;
|
|
public readonly float overAndUnderCenterOpacity;
|
|
public readonly float? itemExtent;
|
|
public readonly float squeeze;
|
|
public readonly bool clipToSize;
|
|
public readonly bool renderChildrenOutsideViewport;
|
|
public readonly ViewportOffset offset;
|
|
public readonly ListWheelChildDelegate childDelegate;
|
|
|
|
public override Element createElement() {
|
|
return new ListWheelElement(this);
|
|
}
|
|
|
|
public override RenderObject createRenderObject(BuildContext context) {
|
|
ListWheelElement childManager = (ListWheelElement) context;
|
|
return new RenderListWheelViewport(
|
|
childManager: childManager,
|
|
offset: offset,
|
|
diameterRatio: diameterRatio,
|
|
perspective: perspective,
|
|
offAxisFraction: offAxisFraction,
|
|
useMagnifier: useMagnifier,
|
|
magnification: magnification,
|
|
overAndUnderCenterOpacity: overAndUnderCenterOpacity,
|
|
itemExtent: itemExtent ?? 1.0f ,
|
|
squeeze: squeeze,
|
|
clipToSize: clipToSize,
|
|
renderChildrenOutsideViewport: renderChildrenOutsideViewport
|
|
);
|
|
}
|
|
|
|
public override void updateRenderObject(BuildContext context, RenderObject renderObject) {
|
|
var viewport = (RenderListWheelViewport) renderObject;
|
|
viewport.offset = offset;
|
|
viewport.diameterRatio = diameterRatio;
|
|
viewport.perspective = perspective;
|
|
viewport.offAxisFraction = offAxisFraction;
|
|
viewport.useMagnifier = useMagnifier;
|
|
viewport.magnification = magnification;
|
|
viewport.overAndUnderCenterOpacity = overAndUnderCenterOpacity;
|
|
viewport.itemExtent = itemExtent ?? 1.0f;
|
|
viewport.squeeze = squeeze;
|
|
viewport.clipToSize = clipToSize;
|
|
viewport.renderChildrenOutsideViewport = renderChildrenOutsideViewport;
|
|
}
|
|
}
|
|
}
|