ElementProxy.cs source code in C# .NET

Source code for the .NET framework in C#

                        

Code:

/ 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / wpf / src / Core / CSharp / MS / Internal / Automation / ElementProxy.cs / 1606164 / ElementProxy.cs

                            //---------------------------------------------------------------------------- 
//
// 
//    Copyright (C) Microsoft Corporation.  All rights reserved.
//  
//
// 
// Description: UIAutomation/Visual bridge 
//
// History: 
//  07/15/2003 : BrendanM Ported to WCP
//
//---------------------------------------------------------------------------
 
using System;
using System.Collections; 
using System.Reflection; 
using System.Runtime.InteropServices;
 
using System.Windows;
using System.Windows.Automation;
using System.Windows.Automation.Provider;
using System.Windows.Automation.Peers; 
using System.Diagnostics;
using System.Windows.Input; 
using System.Windows.Interop; 
using System.Windows.Media;
using System.Windows.Threading; 

using System.Security;
using System.Security.Permissions;
 
using MS.Internal.PresentationCore;
using MS.Win32; 
using SR=MS.Internal.PresentationCore.SR; 
using SRID=MS.Internal.PresentationCore.SRID;
 
namespace MS.Internal.Automation
{
    // Automation Proxy for WCP elements - exposes WCP tree
    // and properties to Automation. 
    //
    // Currently builds tree based on Visual tree; many later incorporate 
    // parts of logical tree. 
    //
    // Currently exposes just BoundingRectangle, ClassName, IsEnabled 
    // and IsKeyboardFocused properties.
    internal class ElementProxy: IRawElementProviderFragmentRoot, IRawElementProviderAdviseEvents
    {
        //----------------------------------------------------- 
        //
        //  Constructors 
        // 
        //-----------------------------------------------------
 
        #region Constructors

        // private ctor - the Wrap() pseudo-ctor is used instead.
        private ElementProxy(AutomationPeer peer) 
        {
            if ((AutomationInteropReferenceType == ReferenceType.Weak) && 
                (peer is UIElementAutomationPeer || peer is ContentElementAutomationPeer || peer is UIElement3DAutomationPeer)) 
            {
                _peer = new WeakReference(peer); 
            }
            else
            {
                _peer = peer; 
            }
        } 
 
        #endregion Constructors
 
        //------------------------------------------------------
        //
        //  Interface IRawElementProviderFragmentRoot
        // 
        //------------	------------------------------------------
 
        #region Interface IRawElementProviderFragmentRoot 
        // Implementation of the interface that exposes this
        // to UIAutomation. 
        //
        // Interface IRawElementProviderFragmentRoot 'derives' from
        // IRawElementProviderSimple and IRawElementProviderFragment,
        // methods from those appear first below. 
        //
        // Most of the interface methods on this interface need 
        // to get onto the Visual's context before they can access it, 
        // so use Dispatcher.Invoke to call a private method (in the
        // private methods section of this class) that does the real work. 

        // IRawElementProviderSimple methods...

        public object GetPatternProvider ( int pattern ) 
        {
            AutomationPeer peer = Peer; 
            if (peer == null) 
            {
                throw new ElementNotAvailableException(); 
            }
            return ElementUtil.Invoke(peer, new DispatcherOperationCallback( InContextGetPatternProvider ), pattern);
        }
 
        public object GetPropertyValue(int property)
        { 
            AutomationPeer peer = Peer; 
            if (peer == null)
            { 
                throw new ElementNotAvailableException();
            }
            return ElementUtil.Invoke(peer, new DispatcherOperationCallback(InContextGetPropertyValue), property);
        } 

        public ProviderOptions ProviderOptions 
        { 
            get
            { 
                AutomationPeer peer = Peer;
                if (peer == null)
                {
                    return ProviderOptions.ServerSideProvider; 
                }
                return (ProviderOptions)ElementUtil.Invoke(peer, new DispatcherOperationCallback( InContextGetProviderOptions ), null); 
            } 
        }
 
        public IRawElementProviderSimple HostRawElementProvider
        {
            get
            { 
                IRawElementProviderSimple host  = null;
                HostedWindowWrapper hwndWrapper = null; 
                AutomationPeer peer = Peer; 
                if (peer == null)
                { 
                    return null;
                }
                hwndWrapper = (HostedWindowWrapper)ElementUtil.Invoke(
                    peer, 
                    new DispatcherOperationCallback(InContextGetHostRawElementProvider),
                    null); 
 
                if(hwndWrapper != null)
                    host = GetHostHelper(hwndWrapper); 

                return host;
            }
        } 

        ///  
        ///     Critical    - Calls critical HostedWindowWrapper.Handle. 
        ///     TreatAsSafe - Critical data is used internally and not explosed
        ///  
        [SecurityCritical, SecurityTreatAsSafe]
        private IRawElementProviderSimple GetHostHelper(HostedWindowWrapper hwndWrapper)
        {
            return AutomationInteropProvider.HostProviderFromHandle(hwndWrapper.Handle); 
        }
 
        // IRawElementProviderFragment methods... 

        public IRawElementProviderFragment Navigate( NavigateDirection direction ) 
        {
            AutomationPeer peer = Peer;
            if (peer == null)
            { 
                return null;
            } 
            return (IRawElementProviderFragment)ElementUtil.Invoke(peer, new DispatcherOperationCallback(InContextNavigate), direction); 
        }
 
        public int [ ] GetRuntimeId()
        {
            AutomationPeer peer = Peer;
            if (peer == null) 
            {
                throw new ElementNotAvailableException(); 
            } 
            return (int []) ElementUtil.Invoke( peer, new DispatcherOperationCallback( InContextGetRuntimeId ), null );
        } 

        public Rect BoundingRectangle
        {
            get 
            {
                AutomationPeer peer = Peer; 
                if (peer == null) 
                {
                    throw new ElementNotAvailableException(); 
                }
                return (Rect)ElementUtil.Invoke(peer, new DispatcherOperationCallback(InContextBoundingRectangle), null);
            }
        } 

        public IRawElementProviderSimple [] GetEmbeddedFragmentRoots() 
        { 
            return null;
        } 

        public void SetFocus()
        {
            AutomationPeer peer = Peer; 
            if (peer == null)
            { 
                throw new ElementNotAvailableException(); 
            }
            ElementUtil.Invoke(peer, new DispatcherOperationCallback( InContextSetFocus ), null); 
        }

        public IRawElementProviderFragmentRoot FragmentRoot
        { 
            get
            { 
                AutomationPeer peer = Peer; 
                if (peer == null)
                { 
                    return null;
                }
                return (IRawElementProviderFragmentRoot) ElementUtil.Invoke( peer, new DispatcherOperationCallback( InContextFragmentRoot ), null );
            } 
        }
 
        // IRawElementProviderFragmentRoot methods.. 
        public IRawElementProviderFragment ElementProviderFromPoint( double x, double y )
        { 
            AutomationPeer peer = Peer;
            if (peer == null)
            {
                return null; 
            }
            return (IRawElementProviderFragment) ElementUtil.Invoke( peer, new DispatcherOperationCallback( InContextElementProviderFromPoint ), new Point( x, y ) ); 
        } 

        public IRawElementProviderFragment GetFocus() 
        {
            AutomationPeer peer = Peer;
            if (peer == null)
            { 
                return null;
            } 
            return (IRawElementProviderFragment) ElementUtil.Invoke( peer, new DispatcherOperationCallback( InContextGetFocus ), null ); 
        }
 
        // Event support: EventMap is a static class and access is synchronized, so no need to access it in UI thread context.
        // Directly add or remove the requested EventId from the EventMap from here.
        // Note: We update the  EventMap even if peer is not available that's because we still have to keep track of number of
        // subscribers  for the given event. 

        public void AdviseEventAdded(int eventID, int[] properties) 
        { 
            EventMap.AddEvent(eventID);
        } 

        public void AdviseEventRemoved(int eventID, int[] properties)
        {
            EventMap.RemoveEvent(eventID); 
        }
 
        #endregion Interface IRawElementProviderFragmentRoot 

        //----------------------------------------------------- 
        //
        //  Internal Methods
        //
        //------------------------------------------------------ 

        #region Internal Methods 
 
        // Wrap the found peer before shipping it over process boundary - static version for use outside ElementProxy.
        internal static ElementProxy StaticWrap(AutomationPeer peer, AutomationPeer referencePeer) 
        {
            ElementProxy result = null;

            if (peer != null) 
            {
                //referencePeer is well-connected, since UIA is asking us using it. 
                //However we are trying to return the peer that is possibly just created on some 
                //element in the middle of un-walked tree and we need to make sure it is fully
                //"connected" or initialized before we return it to UIA. 
                //This method ensures it has the right _parent and other hookup.
                peer = peer.ValidateConnected(referencePeer);
                if (peer != null)
                { 
                    // Use the already created Wrapper proxy for peer if it is still alive
                    if(peer.ElementProxyWeakReference != null) 
                    { 
                        result = peer.ElementProxyWeakReference.Target as ElementProxy;
                    } 
                    if(result == null)
                    {
                        result = new ElementProxy(peer);
                        peer.ElementProxyWeakReference = new WeakReference(result); 
                    }
 
                    // If the peer corresponds to DataItem notify peer to add to storage to 
                    // keep reference of peers going to the UIA Client
                    if(result != null) 
                    {
                        if(peer.IsDataItemAutomationPeer())
                        {
                            peer.AddToParentProxyWeakRefCache(); 
                        }
                    } 
                } 
            }
 
            return result;
        }

 
        // Needed to enable access from AutomationPeer.PeerFromProvider
        internal AutomationPeer Peer 
        { 
            get
            { 
                if (_peer is WeakReference)
                {
                    AutomationPeer peer = (AutomationPeer)((WeakReference)_peer).Target;
                    return peer; 
                }
                else 
                { 
                    return (AutomationPeer)_peer;
                } 
            }
        }

        #endregion Internal Methods 

 
        //------------------------------------------------------ 
        //
        //  Private Methods 
        //
        //-----------------------------------------------------

        #region Private Methods 

        // The signature of most of the folling methods is "object func( object arg )", 
        // since that's what the Conmtext.Invoke delegate requires. 
        // Return the element at specified coords.
        private object InContextElementProviderFromPoint( object arg ) 
        {
            Point point = (Point)arg;
            AutomationPeer peer = Peer;
            if (peer == null) 
            {
                return null; 
            } 
            AutomationPeer peerFromPoint = peer.GetPeerFromPoint(point);
            return StaticWrap(peerFromPoint, peer); 
        }

        // Return proxy representing currently focused element (if any)
        private object InContextGetFocus( object unused ) 
        {
            // 
 

 
            AutomationPeer peer = Peer;
            if (peer == null)
            {
                return null; 
            }
            AutomationPeer focusedPeer = AutomationPeer.AutomationPeerFromInputElement(Keyboard.FocusedElement); 
            return StaticWrap(focusedPeer, peer); 
        }
 
        //  redirect to AutomationPeer
        private object InContextGetPatternProvider(object arg)
        {
            AutomationPeer peer = Peer; 
            if (peer == null)
            { 
                throw new ElementNotAvailableException(); 
            }
            return peer.GetWrappedPattern((int)arg); 
        }

        // Return proxy representing element in specified direction (parent/next/firstchild/etc.)
        private object InContextNavigate( object arg ) 
        {
            NavigateDirection direction = (NavigateDirection) arg; 
            AutomationPeer dest; 
            AutomationPeer peer = Peer;
            if (peer == null) 
            {
                return null;
            }
 
            switch( direction )
            { 
                case NavigateDirection.Parent: 
                    dest = peer.GetParent();
                    break; 

                case NavigateDirection.FirstChild:
                    if (!peer.IsInteropPeer)
                    { 
                        dest = peer.GetFirstChild();
                    } 
                    else 
                    {
                        return peer.GetInteropChild(); 
                    }
                    break;

                case NavigateDirection.LastChild: 
                    if (!peer.IsInteropPeer)
                    { 
                        dest = peer.GetLastChild(); 
                    }
                    else 
                    {
                        return peer.GetInteropChild();
                    }
                    break; 

                case NavigateDirection.NextSibling: 
                    dest = peer.GetNextSibling(); 
                    break;
 
                case NavigateDirection.PreviousSibling:
                    dest = peer.GetPreviousSibling();
                    break;
 
                default:
                    dest = null; 
                    break; 
            }
 
            return StaticWrap(dest, peer);
        }

 
        // Return value for specified property; or null if not supported
        private object InContextGetProviderOptions( object arg ) 
        { 
            ProviderOptions options = ProviderOptions.ServerSideProvider;
            AutomationPeer peer = Peer; 
            if (peer == null)
            {
                return options;
            } 
            if (peer.IsHwndHost)
                options |= ProviderOptions.OverrideProvider; 
 
            return options;
        } 

        // Return value for specified property; or null if not supported
        private object InContextGetPropertyValue ( object arg )
        { 
            AutomationPeer peer = Peer;
            if (peer == null) 
            { 
                throw new ElementNotAvailableException();
            } 
            return peer.GetPropertyValue((int)arg);
        }

        /// Returns whether this is the Root of the WCP tree or not 
        private object InContextGetHostRawElementProvider( object unused )
        { 
            AutomationPeer peer = Peer; 
            if (peer == null)
            { 
                return null;
            }
            return peer.GetHostRawElementProvider();
        } 

        // Return unique ID for this element... 
        private object InContextGetRuntimeId( object unused ) 
        {
            AutomationPeer peer = Peer; 
            if (peer == null)
            {
                throw new ElementNotAvailableException();
            } 
            return peer.GetRuntimeId();
        } 
 
        // Return bounding rectangle (screen coords) for this element...
        private object InContextBoundingRectangle(object unused) 
        {
            AutomationPeer peer = Peer;
            if (peer == null)
            { 
                throw new ElementNotAvailableException();
            } 
            return peer.GetBoundingRectangle(); 
        }
 
        // Set focus to this element...
        private object InContextSetFocus( object unused )
        {
            AutomationPeer peer = Peer; 
            if (peer == null)
            { 
                throw new ElementNotAvailableException(); 
            }
            peer.SetFocus(); 
            return null;
        }

        // Return proxy representing the root of this WCP tree... 
        private object InContextFragmentRoot( object unused )
        { 
            AutomationPeer peer = Peer; 
            AutomationPeer root = peer;
            if (root == null) 
            {
                return null;
            }
            while(true) 
            {
                AutomationPeer parent = root.GetParent(); 
                if(parent == null) break; 
                root = parent;
            } 

            return StaticWrap(root, peer);
        }
 
        #region disable switch for ElementProxy weak reference fix
 
        internal enum ReferenceType 
        {
            Strong, 
            Weak
        }

        // Returns RefrenceType.Strong if key AutomationWeakReferenceDisallow  under 
        // "HKEY_LOCAL_MACHINE\Software\Microsoft\.NETFramework\Windows  Presentation Foundation\Features"
        // is set to 1 else returns ReferenceType.Weak. The registry key will be read only once. 
        internal static ReferenceType AutomationInteropReferenceType 
        {
            /// 
            /// Critical: Uses the critical RegistryKeys.ReadLocalMachineBool() to access the registry.
            /// Safe: This flag is not a secret and used internally
            ///
            [SecurityCritical, SecurityTreatAsSafe] 
            get
            { 
                if (_shouldCheckInTheRegistry) 
                {
                    if (RegistryKeys.ReadLocalMachineBool(RegistryKeys.WPF_Features, RegistryKeys.value_AutomationWeakReferenceDisallow)) 
                    {
                        _automationInteropReferenceType = ReferenceType.Strong;
                    }
                    _shouldCheckInTheRegistry = false; 
                }
                return _automationInteropReferenceType; 
            } 
        }
 
        private static ReferenceType _automationInteropReferenceType = ReferenceType.Weak;
        private static bool _shouldCheckInTheRegistry = true;

        #endregion 

        #endregion Private Methods 
 
        //------------------------------------------------------
        // 
        //  Private Fields
        //
        //-----------------------------------------------------
 
        #region Private Fields
 
        private readonly object _peer; 

        #endregion Private Fields 
    }
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
//---------------------------------------------------------------------------- 
//
// 
//    Copyright (C) Microsoft Corporation.  All rights reserved.
//  
//
// 
// Description: UIAutomation/Visual bridge 
//
// History: 
//  07/15/2003 : BrendanM Ported to WCP
//
//---------------------------------------------------------------------------
 
using System;
using System.Collections; 
using System.Reflection; 
using System.Runtime.InteropServices;
 
using System.Windows;
using System.Windows.Automation;
using System.Windows.Automation.Provider;
using System.Windows.Automation.Peers; 
using System.Diagnostics;
using System.Windows.Input; 
using System.Windows.Interop; 
using System.Windows.Media;
using System.Windows.Threading; 

using System.Security;
using System.Security.Permissions;
 
using MS.Internal.PresentationCore;
using MS.Win32; 
using SR=MS.Internal.PresentationCore.SR; 
using SRID=MS.Internal.PresentationCore.SRID;
 
namespace MS.Internal.Automation
{
    // Automation Proxy for WCP elements - exposes WCP tree
    // and properties to Automation. 
    //
    // Currently builds tree based on Visual tree; many later incorporate 
    // parts of logical tree. 
    //
    // Currently exposes just BoundingRectangle, ClassName, IsEnabled 
    // and IsKeyboardFocused properties.
    internal class ElementProxy: IRawElementProviderFragmentRoot, IRawElementProviderAdviseEvents
    {
        //----------------------------------------------------- 
        //
        //  Constructors 
        // 
        //-----------------------------------------------------
 
        #region Constructors

        // private ctor - the Wrap() pseudo-ctor is used instead.
        private ElementProxy(AutomationPeer peer) 
        {
            if ((AutomationInteropReferenceType == ReferenceType.Weak) && 
                (peer is UIElementAutomationPeer || peer is ContentElementAutomationPeer || peer is UIElement3DAutomationPeer)) 
            {
                _peer = new WeakReference(peer); 
            }
            else
            {
                _peer = peer; 
            }
        } 
 
        #endregion Constructors
 
        //------------------------------------------------------
        //
        //  Interface IRawElementProviderFragmentRoot
        // 
        //------------	------------------------------------------
 
        #region Interface IRawElementProviderFragmentRoot 
        // Implementation of the interface that exposes this
        // to UIAutomation. 
        //
        // Interface IRawElementProviderFragmentRoot 'derives' from
        // IRawElementProviderSimple and IRawElementProviderFragment,
        // methods from those appear first below. 
        //
        // Most of the interface methods on this interface need 
        // to get onto the Visual's context before they can access it, 
        // so use Dispatcher.Invoke to call a private method (in the
        // private methods section of this class) that does the real work. 

        // IRawElementProviderSimple methods...

        public object GetPatternProvider ( int pattern ) 
        {
            AutomationPeer peer = Peer; 
            if (peer == null) 
            {
                throw new ElementNotAvailableException(); 
            }
            return ElementUtil.Invoke(peer, new DispatcherOperationCallback( InContextGetPatternProvider ), pattern);
        }
 
        public object GetPropertyValue(int property)
        { 
            AutomationPeer peer = Peer; 
            if (peer == null)
            { 
                throw new ElementNotAvailableException();
            }
            return ElementUtil.Invoke(peer, new DispatcherOperationCallback(InContextGetPropertyValue), property);
        } 

        public ProviderOptions ProviderOptions 
        { 
            get
            { 
                AutomationPeer peer = Peer;
                if (peer == null)
                {
                    return ProviderOptions.ServerSideProvider; 
                }
                return (ProviderOptions)ElementUtil.Invoke(peer, new DispatcherOperationCallback( InContextGetProviderOptions ), null); 
            } 
        }
 
        public IRawElementProviderSimple HostRawElementProvider
        {
            get
            { 
                IRawElementProviderSimple host  = null;
                HostedWindowWrapper hwndWrapper = null; 
                AutomationPeer peer = Peer; 
                if (peer == null)
                { 
                    return null;
                }
                hwndWrapper = (HostedWindowWrapper)ElementUtil.Invoke(
                    peer, 
                    new DispatcherOperationCallback(InContextGetHostRawElementProvider),
                    null); 
 
                if(hwndWrapper != null)
                    host = GetHostHelper(hwndWrapper); 

                return host;
            }
        } 

        ///  
        ///     Critical    - Calls critical HostedWindowWrapper.Handle. 
        ///     TreatAsSafe - Critical data is used internally and not explosed
        ///  
        [SecurityCritical, SecurityTreatAsSafe]
        private IRawElementProviderSimple GetHostHelper(HostedWindowWrapper hwndWrapper)
        {
            return AutomationInteropProvider.HostProviderFromHandle(hwndWrapper.Handle); 
        }
 
        // IRawElementProviderFragment methods... 

        public IRawElementProviderFragment Navigate( NavigateDirection direction ) 
        {
            AutomationPeer peer = Peer;
            if (peer == null)
            { 
                return null;
            } 
            return (IRawElementProviderFragment)ElementUtil.Invoke(peer, new DispatcherOperationCallback(InContextNavigate), direction); 
        }
 
        public int [ ] GetRuntimeId()
        {
            AutomationPeer peer = Peer;
            if (peer == null) 
            {
                throw new ElementNotAvailableException(); 
            } 
            return (int []) ElementUtil.Invoke( peer, new DispatcherOperationCallback( InContextGetRuntimeId ), null );
        } 

        public Rect BoundingRectangle
        {
            get 
            {
                AutomationPeer peer = Peer; 
                if (peer == null) 
                {
                    throw new ElementNotAvailableException(); 
                }
                return (Rect)ElementUtil.Invoke(peer, new DispatcherOperationCallback(InContextBoundingRectangle), null);
            }
        } 

        public IRawElementProviderSimple [] GetEmbeddedFragmentRoots() 
        { 
            return null;
        } 

        public void SetFocus()
        {
            AutomationPeer peer = Peer; 
            if (peer == null)
            { 
                throw new ElementNotAvailableException(); 
            }
            ElementUtil.Invoke(peer, new DispatcherOperationCallback( InContextSetFocus ), null); 
        }

        public IRawElementProviderFragmentRoot FragmentRoot
        { 
            get
            { 
                AutomationPeer peer = Peer; 
                if (peer == null)
                { 
                    return null;
                }
                return (IRawElementProviderFragmentRoot) ElementUtil.Invoke( peer, new DispatcherOperationCallback( InContextFragmentRoot ), null );
            } 
        }
 
        // IRawElementProviderFragmentRoot methods.. 
        public IRawElementProviderFragment ElementProviderFromPoint( double x, double y )
        { 
            AutomationPeer peer = Peer;
            if (peer == null)
            {
                return null; 
            }
            return (IRawElementProviderFragment) ElementUtil.Invoke( peer, new DispatcherOperationCallback( InContextElementProviderFromPoint ), new Point( x, y ) ); 
        } 

        public IRawElementProviderFragment GetFocus() 
        {
            AutomationPeer peer = Peer;
            if (peer == null)
            { 
                return null;
            } 
            return (IRawElementProviderFragment) ElementUtil.Invoke( peer, new DispatcherOperationCallback( InContextGetFocus ), null ); 
        }
 
        // Event support: EventMap is a static class and access is synchronized, so no need to access it in UI thread context.
        // Directly add or remove the requested EventId from the EventMap from here.
        // Note: We update the  EventMap even if peer is not available that's because we still have to keep track of number of
        // subscribers  for the given event. 

        public void AdviseEventAdded(int eventID, int[] properties) 
        { 
            EventMap.AddEvent(eventID);
        } 

        public void AdviseEventRemoved(int eventID, int[] properties)
        {
            EventMap.RemoveEvent(eventID); 
        }
 
        #endregion Interface IRawElementProviderFragmentRoot 

        //----------------------------------------------------- 
        //
        //  Internal Methods
        //
        //------------------------------------------------------ 

        #region Internal Methods 
 
        // Wrap the found peer before shipping it over process boundary - static version for use outside ElementProxy.
        internal static ElementProxy StaticWrap(AutomationPeer peer, AutomationPeer referencePeer) 
        {
            ElementProxy result = null;

            if (peer != null) 
            {
                //referencePeer is well-connected, since UIA is asking us using it. 
                //However we are trying to return the peer that is possibly just created on some 
                //element in the middle of un-walked tree and we need to make sure it is fully
                //"connected" or initialized before we return it to UIA. 
                //This method ensures it has the right _parent and other hookup.
                peer = peer.ValidateConnected(referencePeer);
                if (peer != null)
                { 
                    // Use the already created Wrapper proxy for peer if it is still alive
                    if(peer.ElementProxyWeakReference != null) 
                    { 
                        result = peer.ElementProxyWeakReference.Target as ElementProxy;
                    } 
                    if(result == null)
                    {
                        result = new ElementProxy(peer);
                        peer.ElementProxyWeakReference = new WeakReference(result); 
                    }
 
                    // If the peer corresponds to DataItem notify peer to add to storage to 
                    // keep reference of peers going to the UIA Client
                    if(result != null) 
                    {
                        if(peer.IsDataItemAutomationPeer())
                        {
                            peer.AddToParentProxyWeakRefCache(); 
                        }
                    } 
                } 
            }
 
            return result;
        }

 
        // Needed to enable access from AutomationPeer.PeerFromProvider
        internal AutomationPeer Peer 
        { 
            get
            { 
                if (_peer is WeakReference)
                {
                    AutomationPeer peer = (AutomationPeer)((WeakReference)_peer).Target;
                    return peer; 
                }
                else 
                { 
                    return (AutomationPeer)_peer;
                } 
            }
        }

        #endregion Internal Methods 

 
        //------------------------------------------------------ 
        //
        //  Private Methods 
        //
        //-----------------------------------------------------

        #region Private Methods 

        // The signature of most of the folling methods is "object func( object arg )", 
        // since that's what the Conmtext.Invoke delegate requires. 
        // Return the element at specified coords.
        private object InContextElementProviderFromPoint( object arg ) 
        {
            Point point = (Point)arg;
            AutomationPeer peer = Peer;
            if (peer == null) 
            {
                return null; 
            } 
            AutomationPeer peerFromPoint = peer.GetPeerFromPoint(point);
            return StaticWrap(peerFromPoint, peer); 
        }

        // Return proxy representing currently focused element (if any)
        private object InContextGetFocus( object unused ) 
        {
            // 
 

 
            AutomationPeer peer = Peer;
            if (peer == null)
            {
                return null; 
            }
            AutomationPeer focusedPeer = AutomationPeer.AutomationPeerFromInputElement(Keyboard.FocusedElement); 
            return StaticWrap(focusedPeer, peer); 
        }
 
        //  redirect to AutomationPeer
        private object InContextGetPatternProvider(object arg)
        {
            AutomationPeer peer = Peer; 
            if (peer == null)
            { 
                throw new ElementNotAvailableException(); 
            }
            return peer.GetWrappedPattern((int)arg); 
        }

        // Return proxy representing element in specified direction (parent/next/firstchild/etc.)
        private object InContextNavigate( object arg ) 
        {
            NavigateDirection direction = (NavigateDirection) arg; 
            AutomationPeer dest; 
            AutomationPeer peer = Peer;
            if (peer == null) 
            {
                return null;
            }
 
            switch( direction )
            { 
                case NavigateDirection.Parent: 
                    dest = peer.GetParent();
                    break; 

                case NavigateDirection.FirstChild:
                    if (!peer.IsInteropPeer)
                    { 
                        dest = peer.GetFirstChild();
                    } 
                    else 
                    {
                        return peer.GetInteropChild(); 
                    }
                    break;

                case NavigateDirection.LastChild: 
                    if (!peer.IsInteropPeer)
                    { 
                        dest = peer.GetLastChild(); 
                    }
                    else 
                    {
                        return peer.GetInteropChild();
                    }
                    break; 

                case NavigateDirection.NextSibling: 
                    dest = peer.GetNextSibling(); 
                    break;
 
                case NavigateDirection.PreviousSibling:
                    dest = peer.GetPreviousSibling();
                    break;
 
                default:
                    dest = null; 
                    break; 
            }
 
            return StaticWrap(dest, peer);
        }

 
        // Return value for specified property; or null if not supported
        private object InContextGetProviderOptions( object arg ) 
        { 
            ProviderOptions options = ProviderOptions.ServerSideProvider;
            AutomationPeer peer = Peer; 
            if (peer == null)
            {
                return options;
            } 
            if (peer.IsHwndHost)
                options |= ProviderOptions.OverrideProvider; 
 
            return options;
        } 

        // Return value for specified property; or null if not supported
        private object InContextGetPropertyValue ( object arg )
        { 
            AutomationPeer peer = Peer;
            if (peer == null) 
            { 
                throw new ElementNotAvailableException();
            } 
            return peer.GetPropertyValue((int)arg);
        }

        /// Returns whether this is the Root of the WCP tree or not 
        private object InContextGetHostRawElementProvider( object unused )
        { 
            AutomationPeer peer = Peer; 
            if (peer == null)
            { 
                return null;
            }
            return peer.GetHostRawElementProvider();
        } 

        // Return unique ID for this element... 
        private object InContextGetRuntimeId( object unused ) 
        {
            AutomationPeer peer = Peer; 
            if (peer == null)
            {
                throw new ElementNotAvailableException();
            } 
            return peer.GetRuntimeId();
        } 
 
        // Return bounding rectangle (screen coords) for this element...
        private object InContextBoundingRectangle(object unused) 
        {
            AutomationPeer peer = Peer;
            if (peer == null)
            { 
                throw new ElementNotAvailableException();
            } 
            return peer.GetBoundingRectangle(); 
        }
 
        // Set focus to this element...
        private object InContextSetFocus( object unused )
        {
            AutomationPeer peer = Peer; 
            if (peer == null)
            { 
                throw new ElementNotAvailableException(); 
            }
            peer.SetFocus(); 
            return null;
        }

        // Return proxy representing the root of this WCP tree... 
        private object InContextFragmentRoot( object unused )
        { 
            AutomationPeer peer = Peer; 
            AutomationPeer root = peer;
            if (root == null) 
            {
                return null;
            }
            while(true) 
            {
                AutomationPeer parent = root.GetParent(); 
                if(parent == null) break; 
                root = parent;
            } 

            return StaticWrap(root, peer);
        }
 
        #region disable switch for ElementProxy weak reference fix
 
        internal enum ReferenceType 
        {
            Strong, 
            Weak
        }

        // Returns RefrenceType.Strong if key AutomationWeakReferenceDisallow  under 
        // "HKEY_LOCAL_MACHINE\Software\Microsoft\.NETFramework\Windows  Presentation Foundation\Features"
        // is set to 1 else returns ReferenceType.Weak. The registry key will be read only once. 
        internal static ReferenceType AutomationInteropReferenceType 
        {
            /// 
            /// Critical: Uses the critical RegistryKeys.ReadLocalMachineBool() to access the registry.
            /// Safe: This flag is not a secret and used internally
            ///
            [SecurityCritical, SecurityTreatAsSafe] 
            get
            { 
                if (_shouldCheckInTheRegistry) 
                {
                    if (RegistryKeys.ReadLocalMachineBool(RegistryKeys.WPF_Features, RegistryKeys.value_AutomationWeakReferenceDisallow)) 
                    {
                        _automationInteropReferenceType = ReferenceType.Strong;
                    }
                    _shouldCheckInTheRegistry = false; 
                }
                return _automationInteropReferenceType; 
            } 
        }
 
        private static ReferenceType _automationInteropReferenceType = ReferenceType.Weak;
        private static bool _shouldCheckInTheRegistry = true;

        #endregion 

        #endregion Private Methods 
 
        //------------------------------------------------------
        // 
        //  Private Fields
        //
        //-----------------------------------------------------
 
        #region Private Fields
 
        private readonly object _peer; 

        #endregion Private Fields 
    }
}

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

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