InheritanceContextChangedEventManager.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / wpf / src / Base / MS / Internal / InheritanceContextChangedEventManager.cs / 1305600 / InheritanceContextChangedEventManager.cs
                        

                        
                            //---------------------------------------------------------------------------- 
//
// 
//    Copyright (C) Microsoft Corporation.  All rights reserved.
//  
//
// Description: Manager for the InheritanceContextChanged event in the "weak event listener" 
//              pattern.  See WeakEventTable.cs for an overview. 
//
//--------------------------------------------------------------------------- 

using System;
using System.Diagnostics;
using System.Windows;       // WeakEventManager 
using MS.Internal.WindowsBase;  // [FriendAccessAllowed]
 
namespace MS.Internal 
{
    ///  
    /// Manager for the DependencyObject.InheritanceContextChanged event.
    /// 
    [FriendAccessAllowed]
    internal class InheritanceContextChangedEventManager : WeakEventManager 
    {
        #region Constructors 
 
        //
        //  Constructors 
        //

        private InheritanceContextChangedEventManager()
        { 
        }
 
        #endregion Constructors 

        #region Public Methods 

        //
        //  Public Methods
        // 

        ///  
        /// Add a listener to the given source's event. 
        /// 
        public static void AddListener(DependencyObject source, IWeakEventListener listener) 
        {
            if (source == null)
                throw new ArgumentNullException("source");
            if (listener == null) 
                throw new ArgumentNullException("listener");
 
            // Freezable.Freeze() relies on the assumption that a frozen Freezable 
            // has no listeners.  This is because Freeze() fails if the Freezable
            // has any Expressions on it, and only Expressions ever listen 
            // to the InheritanceContextChanged event.
            Debug.Assert(listener is Expression);

            CurrentManager.ProtectedAddListener(source, listener); 
        }
 
        ///  
        /// Remove a listener to the given source's event.
        ///  
        public static void RemoveListener(DependencyObject source, IWeakEventListener listener)
        {
            if (source == null)
                throw new ArgumentNullException("source"); 
            if (listener == null)
                throw new ArgumentNullException("listener"); 
 
            CurrentManager.ProtectedRemoveListener(source, listener);
        } 

        #endregion Public Methods

        #region Protected Methods 

        // 
        //  Protected Methods 
        //
 
        /// 
        /// Listen to the given source for the event.
        /// 
        protected override void StartListening(object source) 
        {
            DependencyObject typedSource = (DependencyObject)source; 
            typedSource.InheritanceContextChanged += new EventHandler(OnInheritanceContextChanged); 
        }
 
        /// 
        /// Stop listening to the given source for the event.
        /// 
        protected override void StopListening(object source) 
        {
            DependencyObject typedSource = (DependencyObject)source; 
            typedSource.InheritanceContextChanged -= new EventHandler(OnInheritanceContextChanged); 
        }
 
        #endregion Protected Methods

        #region Private Properties
 
        //
        //  Private Properties 
        // 

        // get the event manager for the current thread 
        private static InheritanceContextChangedEventManager CurrentManager
        {
            get
            { 
                Type managerType = typeof(InheritanceContextChangedEventManager);
                InheritanceContextChangedEventManager manager = (InheritanceContextChangedEventManager)GetCurrentManager(managerType); 
 
                // at first use, create and register a new manager
                if (manager == null) 
                {
                    manager = new InheritanceContextChangedEventManager();
                    SetCurrentManager(managerType, manager);
                } 

                return manager; 
            } 
        }
 
        #endregion Private Properties

        #region Private Methods
 
        //
        //  Private Methods 
        // 

        // event handler for InheritanceContextChanged event 
        private void OnInheritanceContextChanged(object sender, EventArgs args)
        {
            DeliverEvent(sender, args);
        } 

        #endregion Private Methods 
    } 
}
 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.

Link Menu

Network programming in C#, Network Programming in VB.NET, Network Programming in .NET
This book is available now!
Buy at Amazon US or
Buy at Amazon UK