TextViewWeakEventManager.cs

// Copyright (c) 2014 AlphaSierraPapa for the SharpDevelop Team
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy of this
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// to whom the Software is furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in all copies or
// substantial portions of the Software.
// 
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// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
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using System;
using Unity.CodeEditor.Utils;

namespace Unity.CodeEditor.Rendering
{
    /// <summary>
    /// Contains weak event managers for the TextView events.
    /// </summary>
    internal static class TextViewWeakEventManager
    {
        /// <summary>
        /// Weak event manager for the <see cref="TextView.DocumentChanged"/> event.
        /// </summary>
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1034:NestedTypesShouldNotBeVisible")]
        internal sealed class DocumentChanged : WeakEventManagerBase<DocumentChanged, TextView, EventHandler, EventArgs>
        {
            protected override void StartListening(TextView source) => source.DocumentChanged += DeliverEvent;

            protected override void StopListening(TextView source) => source.DocumentChanged -= DeliverEvent;
        }

        /// <summary>
        /// Weak event manager for the <see cref="TextView.VisualLinesChanged"/> event.
        /// </summary>
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1034:NestedTypesShouldNotBeVisible")]
        internal sealed class VisualLinesChanged : WeakEventManagerBase<VisualLinesChanged, TextView, EventHandler, EventArgs>
        {
            protected override void StartListening(TextView source) => source.VisualLinesChanged += DeliverEvent;

            protected override void StopListening(TextView source) => source.VisualLinesChanged -= DeliverEvent;
        }

        /// <summary>
        /// Weak event manager for the <see cref="TextView.ScrollOffsetChanged"/> event.
        /// </summary>
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1034:NestedTypesShouldNotBeVisible")]
        internal sealed class ScrollOffsetChanged : WeakEventManagerBase<ScrollOffsetChanged, TextView, EventHandler, EventArgs>
        {
            protected override void StartListening(TextView source) => source.ScrollOffsetChanged += DeliverEvent;

            protected override void StopListening(TextView source) => source.ScrollOffsetChanged -= DeliverEvent;
        }
    }
}