34 lines
1.2 KiB
C#
34 lines
1.2 KiB
C#
// Licensed to the .NET Foundation under one or more agreements.
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// The .NET Foundation licenses this file to you under the MIT license.
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// See the LICENSE file in the project root for more information.
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using System.Collections;
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using System.Collections.Specialized;
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using System.ComponentModel;
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namespace CommunityToolkit.Mvvm.Collections;
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/// <summary>
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/// An interface for a grouped collection of items.
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/// </summary>
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public interface IReadOnlyObservableGroup : INotifyPropertyChanged, INotifyCollectionChanged, IEnumerable
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{
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/// <summary>
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/// Gets the key for the current collection.
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/// </summary>
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object Key { get; }
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/// <summary>
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/// Gets the number of items currently in the grouped collection.
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/// </summary>
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int Count { get; }
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/// <summary>
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/// Gets the element at the specified index in the current collection.
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/// </summary>
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/// <param name="index">The zero-based index of the element to get.</param>
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/// <returns>The element at the specified index in the read-only list.</returns>
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/// <exception cref="System.ArgumentOutOfRangeException">Thrown if the index is out of range.</exception>
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object? this[int index] { get; }
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}
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