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MackinnonBuckMackinnonBuck
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Restructured + infinite scroll
1 parent 96948a3 commit 5a9fe7a

17 files changed

+490
-168
lines changed

‎src/Components/Components/ref/Microsoft.AspNetCore.Components.netcoreapp.cs

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@@ -587,3 +587,60 @@ public void Dispose() { }
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public System.Threading.Tasks.Task SetParametersAsync(Microsoft.AspNetCore.Components.ParameterView parameters) { throw null; }
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}
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}
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namespace Microsoft.AspNetCore.Components.Virtualization
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{
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public sealed partial class InfiniteScroll<TItem> : Microsoft.AspNetCore.Components.Virtualization.VirtualizeBase<TItem>
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{
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public InfiniteScroll() { }
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[Microsoft.AspNetCore.Components.ParameterAttribute]
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public Microsoft.AspNetCore.Components.RenderFragment? InfiniteScrollFooter { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } [System.Runtime.CompilerServices.CompilerGeneratedAttribute] set { } }
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[Microsoft.AspNetCore.Components.ParameterAttribute]
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public Microsoft.AspNetCore.Components.RenderFragment<TItem> Item { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } [System.Runtime.CompilerServices.CompilerGeneratedAttribute] set { } }
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[Microsoft.AspNetCore.Components.ParameterAttribute]
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public int ItemBatchSize { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } [System.Runtime.CompilerServices.CompilerGeneratedAttribute] set { } }
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protected override int ItemCount { get { throw null; } }
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[Microsoft.AspNetCore.Components.ParameterAttribute]
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public System.Func<System.Range, System.Threading.Tasks.Task<System.Collections.Generic.IEnumerable<TItem>>> ItemsProvider { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } [System.Runtime.CompilerServices.CompilerGeneratedAttribute] set { } }
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protected override System.Collections.Generic.IEnumerable<Microsoft.AspNetCore.Components.RenderFragment> GetItems(int start, int count) { throw null; }
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}
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public partial interface IVirtualizationHelper : System.IAsyncDisposable
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{
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event System.EventHandler<Microsoft.AspNetCore.Components.Virtualization.SpacerEventArgs> BottomSpacerVisible;
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event System.EventHandler<Microsoft.AspNetCore.Components.Virtualization.SpacerEventArgs> TopSpacerVisible;
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System.Threading.Tasks.ValueTask InitAsync(Microsoft.AspNetCore.Components.ElementReference topSpacer, Microsoft.AspNetCore.Components.ElementReference bottomSpacer);
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}
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public partial interface IVirtualizationService
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{
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Microsoft.AspNetCore.Components.Virtualization.IVirtualizationHelper CreateVirtualizationHelper();
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}
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public partial class SpacerEventArgs : System.EventArgs
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{
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public SpacerEventArgs(float spacerSize, float containerSize) { }
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public float ContainerSize { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } }
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public float SpacerSize { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } }
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}
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public abstract partial class VirtualizeBase<TItem> : Microsoft.AspNetCore.Components.ComponentBase, System.IAsyncDisposable
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{
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protected VirtualizeBase() { }
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protected abstract int ItemCount { get; }
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[Microsoft.AspNetCore.Components.ParameterAttribute]
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public float ItemSize { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } [System.Runtime.CompilerServices.CompilerGeneratedAttribute] set { } }
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protected override void BuildRenderTree(Microsoft.AspNetCore.Components.Rendering.RenderTreeBuilder builder) { }
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[System.Diagnostics.DebuggerStepThroughAttribute]
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public System.Threading.Tasks.ValueTask DisposeAsync() { throw null; }
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protected abstract System.Collections.Generic.IEnumerable<Microsoft.AspNetCore.Components.RenderFragment> GetItems(int start, int count);
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[System.Diagnostics.DebuggerStepThroughAttribute]
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protected override System.Threading.Tasks.Task OnAfterRenderAsync(bool firstRender) { throw null; }
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protected override void OnParametersSet() { }
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}
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public sealed partial class Virtualize<TItem> : Microsoft.AspNetCore.Components.Virtualization.VirtualizeBase<TItem>
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{
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public Virtualize() { }
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[Microsoft.AspNetCore.Components.ParameterAttribute]
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public Microsoft.AspNetCore.Components.RenderFragment<TItem>? ChildContent { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } [System.Runtime.CompilerServices.CompilerGeneratedAttribute] set { } }
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protected override int ItemCount { get { throw null; } }
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[Microsoft.AspNetCore.Components.ParameterAttribute]
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public System.Collections.Generic.ICollection<TItem> Items { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } [System.Runtime.CompilerServices.CompilerGeneratedAttribute] set { } }
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protected override System.Collections.Generic.IEnumerable<Microsoft.AspNetCore.Components.RenderFragment> GetItems(int start, int count) { throw null; }
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}
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}

‎src/Components/Components/src/Virtualization/IVirtualizationHelper.cs

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// Copyright (c) .NET Foundation. All rights reserved.
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// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
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using System;
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using System.Threading.Tasks;
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namespace Microsoft.AspNetCore.Components.Virtualization
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{
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/// <summary>
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/// Describes a helper for detecting and relaying virtualization events.
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/// </summary>
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public interface IVirtualizationHelper : IAsyncDisposable
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{
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/// <summary>
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/// Performs platform-specific initialization.
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/// </summary>
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/// <param name="topSpacer">The <see cref="ElementReference"/> representing the top spacer.</param>
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/// <param name="bottomSpacer">The <see cref="ElementReference"/> representing the bottom spacer.</param>
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/// <returns>The <see cref="ValueTask"/> associated with the completion of this operation.</returns>
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ValueTask InitAsync(ElementReference topSpacer, ElementReference bottomSpacer);
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/// <summary>
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/// Invoked when the top spacer becomes visible.
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/// </summary>
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event EventHandler<SpacerEventArgs> TopSpacerVisible;
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/// <summary>
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/// Invoked when the bottom spacer becomes visible.
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/// </summary>
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event EventHandler<SpacerEventArgs> BottomSpacerVisible;
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}
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}

‎src/Components/Components/src/Virtualization/IVirtualizationService.cs

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// Copyright (c) .NET Foundation. All rights reserved.
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// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
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namespace Microsoft.AspNetCore.Components.Virtualization
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{
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/// <summary>
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/// Describes services enabling platform-specific virtualization.
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/// </summary>
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public interface IVirtualizationService
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{
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/// <summary>
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/// Creates a helper used for detecting and relaying virtualization events.
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/// </summary>
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/// <returns></returns>
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IVirtualizationHelper CreateVirtualizationHelper();
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}
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}

‎src/Components/Components/src/Virtualization/InfiniteScroll.cs

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// Copyright (c) .NET Foundation. All rights reserved.
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// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
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using System;
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using System.Collections.Concurrent;
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using System.Collections.Generic;
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using System.Linq;
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using System.Threading;
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using System.Threading.Tasks;
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namespace Microsoft.AspNetCore.Components.Virtualization
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{
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/// <summary>
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/// Provides functionality for rendering a virtualized, infinite list of items.
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/// </summary>
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/// <typeparam name="TItem">The <c>context</c> type for the items being rendered.</typeparam>
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public sealed class InfiniteScroll<TItem> : VirtualizeBase<TItem>
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{
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private readonly ConcurrentQueue<TItem> _loadedItems = new ConcurrentQueue<TItem>();
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private int _fetchingItems;
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protected override int ItemCount => InfiniteScrollFooter == null ? _loadedItems.Count : _loadedItems.Count + 1;
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/// <summary>
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/// Gets or sets the list item template.
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/// </summary>
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[Parameter]
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public RenderFragment<TItem> Item { get; set; } = default!;
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/// <summary>
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/// Gets or sets the infinite scroll footer template.
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/// </summary>
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[Parameter]
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public RenderFragment? InfiniteScrollFooter { get; set; }
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/// <summary>
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/// Gets or sets the function that provides items for the inifinite scroll.
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/// </summary>
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[Parameter]
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public Func<Range, Task<IEnumerable<TItem>>> ItemsProvider { get; set; } = default!;
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/// <summary>
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/// The batch size in which items are fetched.
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/// </summary>
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[Parameter]
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public int ItemBatchSize { get; set; }
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protected override IEnumerable<RenderFragment> GetItems(int start, int count)
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{
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if (start + count >= _loadedItems.Count)
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{
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// Fetch more items if we're not already
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FetchItemsAsync();
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var items = _loadedItems.Skip(start).Select(item => Item(item));
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return InfiniteScrollFooter == null ? items : items.Append(InfiniteScrollFooter);
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}
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else
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{
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return _loadedItems.Skip(start).Take(count).Select(item => Item(item));
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}
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}
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private void FetchItemsAsync()
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{
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if (Interlocked.Exchange(ref _fetchingItems, 1) == 0)
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{
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ItemsProvider(new Range(_loadedItems.Count, _loadedItems.Count + ItemBatchSize)).ContinueWith(t =>
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{
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foreach (var item in t.Result)
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{
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_loadedItems.Enqueue(item);
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}
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_fetchingItems = 0;
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InvokeAsync(() => StateHasChanged());
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});
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}
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}
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}
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}

‎src/Components/Components/src/Virtualization/SpacerEventArgs.cs

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// Copyright (c) .NET Foundation. All rights reserved.
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// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
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using System;
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namespace Microsoft.AspNetCore.Components.Virtualization
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{
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/// <summary>
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/// Describes an event involving a spacer in a virtualized list.
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/// </summary>
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public class SpacerEventArgs : EventArgs
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{
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/// <summary>
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/// The new size of the spacer.
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/// </summary>
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public float SpacerSize { get; }
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/// <summary>
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/// The current size of the spacer's container.
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/// </summary>
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public float ContainerSize { get; }
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/// <summary>
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/// Instantiates a new <see cref="SpacerEventArgs"/> instance.
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/// </summary>
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/// <param name="spacerSize">The new size of the spacer.</param>
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/// <param name="containerSize">The current size of the spacer's container.</param>
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public SpacerEventArgs(float spacerSize, float containerSize)
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{
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SpacerSize = spacerSize;
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ContainerSize = containerSize;
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}
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}
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}

‎src/Components/Components/src/Virtualization/Virtualize.cs

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// Copyright (c) .NET Foundation. All rights reserved.
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// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
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using System.Collections.Generic;
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using System.Linq;
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namespace Microsoft.AspNetCore.Components.Virtualization
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{
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/// <summary>
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/// Provides functionality for rendering a virtualized, fixed-size list of items.
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/// </summary>
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/// <typeparam name="TItem">The <c>context</c> type for the items being rendered.</typeparam>
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public sealed class Virtualize<TItem> : VirtualizeBase<TItem>
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{
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protected override int ItemCount => Items.Count;
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/// <summary>
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/// Gets or sets the content template for list items.
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/// </summary>
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[Parameter]
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public RenderFragment<TItem>? ChildContent { get; set; }
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/// <summary>
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/// Gets or sets the collection of items used to generate the list.
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/// </summary>
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[Parameter]
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public ICollection<TItem> Items { get; set; } = default!;
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protected override IEnumerable<RenderFragment> GetItems(int start, int count)
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{
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return ChildContent == null ?
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Enumerable.Empty<RenderFragment>() :
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Items.Skip(start).Take(count).Select(item => ChildContent.Invoke(item));
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}
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}
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}

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