Task Manager

//Copyright (c) Microsoft Corporation.  All rights reserved.

using System;
using System.Runtime.InteropServices;
using Microsoft.WindowsAPICodePack.Controls.WindowsForms;
using Microsoft.WindowsAPICodePack.Controls;

namespace MS.WindowsAPICodePack.Internal
{
    /// <summary>
    /// This provides a connection point container compatible dispatch interface for
    /// hooking into the ExplorerBrowser view.
    /// </summary>
    [ComVisible( true )]
    [ClassInterface( ClassInterfaceType.AutoDual )]
    public class ExplorerBrowserViewEvents
    {
        #region implementation
        private uint viewConnectionPointCookie = 0;
        private object viewDispatch = null;
        private IntPtr nullPtr = IntPtr.Zero;

        private Guid IID_DShellFolderViewEvents = new Guid( ExplorerBrowserIIDGuid.DShellFolderViewEvents );
        private Guid IID_IDispatch = new Guid( ExplorerBrowserIIDGuid.IDispatch );
        private ExplorerBrowser parent = null;
        #endregion

        #region contstruction
        internal ExplorerBrowserViewEvents( ExplorerBrowser parent )
        {
            this.parent = parent;
        }
        #endregion

        #region operations
        internal void ConnectToView( IShellView psv )
        {
            DisconnectFromView( );

            HRESULT hr = psv.GetItemObject(
                SVGIO.SVGIO_BACKGROUND,
                ref IID_IDispatch,
                out viewDispatch );

            if( hr == HRESULT.S_OK )
            {
                hr = ExplorerBrowserNativeMethods.ConnectToConnectionPoint(
                    this,
                    ref IID_DShellFolderViewEvents,
                    true,
                    viewDispatch,
                    ref viewConnectionPointCookie,
                    ref nullPtr );

                if( hr != HRESULT.S_OK )
                {
                    Marshal.ReleaseComObject( viewDispatch );
                }
            }
        }

        internal void DisconnectFromView( )
        {
            if( viewDispatch != null )
            {
                ExplorerBrowserNativeMethods.ConnectToConnectionPoint(
                    IntPtr.Zero,
                    ref IID_DShellFolderViewEvents,
                    false,
                    viewDispatch,
                    ref viewConnectionPointCookie,
                    ref nullPtr );

                Marshal.ReleaseComObject( viewDispatch );
                viewDispatch = null;
                viewConnectionPointCookie = 0;
            }
        }
        #endregion

        #region IDispatch events
        // These need to be public to be accessible via AutoDual reflection

        /// <summary>
        /// The view selection has changed
        /// </summary>
        [DispId( ExplorerBrowserViewDispatchIds.SelectionChanged )]
        public void ViewSelectionChanged( )
        {
            parent.FireSelectionChanged( );
        }

        /// <summary>
        /// The contents of the view have changed
        /// </summary>
        [DispId( ExplorerBrowserViewDispatchIds.ContentsChanged )]
        public void ViewContentsChanged( )
        {
            parent.FireContentChanged( );
        }

        /// <summary>
        /// The enumeration of files in the view is complete
        /// </summary>
        [DispId( ExplorerBrowserViewDispatchIds.FileListEnumDone )]
        public void ViewFileListEnumDone( )
        {
            parent.FireContentEnumerationComplete( );
        }

        /// <summary>
        /// The selected item in the view has changed (not the same as the selection has changed)
        /// </summary>
        [DispId( ExplorerBrowserViewDispatchIds.SelectedItemChanged )]
        public void ViewSelectedItemChanged( )
        {
            parent.FireSelectedItemChanged( );
        }
        #endregion
    }
}