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using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.ComponentModel;
using System.Runtime.InteropServices;
using System.Security;
using System.Text;
using System.Windows;
using System.Windows.Automation;
using System.Windows.Automation.Provider;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Interop;
using System.Windows.Media;
using MS.Internal;
using MS.Internal.Automation;
using MS.Win32;
namespace System.Windows.Automation.Peers
{
/// <summary>
/// GridView automation peer
/// </summary>
/// <remarks>
/// Basically, the idea is to add a virtual method called CreateAutomationPeer on ViewBase
/// Any view can override this method to create its own automation peer.
/// ListView will use this method to get an automation peer for a given view and default to
/// the properties/methods/patterns implemented by the view before going to default fall-backs on it
/// These view automation peer must implement IViewAutomationPeer interface
/// </remarks>
public class GridViewAutomationPeer : IViewAutomationPeer, ITableProvider
{
///
public GridViewAutomationPeer(GridView owner, ListView listview)
: base()
{
Invariant.Assert(owner != null);
Invariant.Assert(listview != null);
_owner = owner;
_listview = listview;
//Remember the items/columns count when GVAP is created, this is used for firing RowCount/ColumnCount changed event
_oldItemsCount = _listview.Items.Count;
_oldColumnsCount = _owner.Columns.Count;
((INotifyCollectionChanged)_owner.Columns).CollectionChanged += new NotifyCollectionChangedEventHandler(OnColumnCollectionChanged);
}
///
AutomationControlType IViewAutomationPeer.GetAutomationControlType()
{
return AutomationControlType.DataGrid;
}
///
object IViewAutomationPeer.GetPattern(PatternInterface patternInterface)
{
object ret = null;
switch (patternInterface)
{
case PatternInterface.Grid:
case PatternInterface.Table:
ret = this;
break;
}
return ret;
}
///
List<AutomationPeer> IViewAutomationPeer.GetChildren(List<AutomationPeer> children)
{
//Add GridViewHeaderRowPresenter as the first child of ListView
if (_owner.HeaderRowPresenter != null)
{
AutomationPeer peer = UIElementAutomationPeer.CreatePeerForElement(_owner.HeaderRowPresenter);
if (peer != null)
{
//If children is null, we still need to create an empty list to insert HeaderRowPresenter
if (children == null)
{
children = new List<AutomationPeer>();
}
children.Insert(0, peer);
}
}
return children;
}
ItemAutomationPeer IViewAutomationPeer.CreateItemAutomationPeer(object item)
{
ListViewAutomationPeer lvAP = UIElementAutomationPeer.FromElement(_listview) as ListViewAutomationPeer;
return new GridViewItemAutomationPeer(item, lvAP);
}
///
void IViewAutomationPeer.ItemsChanged(NotifyCollectionChangedEventArgs e)
{
ListViewAutomationPeer peer = UIElementAutomationPeer.FromElement(_listview) as ListViewAutomationPeer;
if (peer != null)
{
if (_oldItemsCount != _listview.Items.Count)
{
peer.RaisePropertyChangedEvent(GridPatternIdentifiers.RowCountProperty, _oldItemsCount, _listview.Items.Count);
}
_oldItemsCount = _listview.Items.Count;
}
}
//Called when the view is detached from the listview
// Note: see bug 1555137 for details.
// Never inline, as we don't want to unnecessarily link the
// automation DLL via the ITableProvider, IGridProvider interface type initialization.
[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.NoInlining)]
void IViewAutomationPeer.ViewDetached()
{
((INotifyCollectionChanged)_owner.Columns).CollectionChanged -= new NotifyCollectionChangedEventHandler(OnColumnCollectionChanged);
}
#region ITableProvider
/// <summary>
/// Indicates if the data is best presented by row or column
/// </summary>
RowOrColumnMajor ITableProvider.RowOrColumnMajor
{
get { return RowOrColumnMajor.RowMajor; }
}
/// <summary>
/// Collection of column headers
/// </summary>
IRawElementProviderSimple[] ITableProvider.GetColumnHeaders()
{
if (_owner.HeaderRowPresenter != null)
{
List<IRawElementProviderSimple> array = new List<IRawElementProviderSimple>(_owner.HeaderRowPresenter.ActualColumnHeaders.Count);
ListViewAutomationPeer lvpeer = UIElementAutomationPeer.FromElement(_listview) as ListViewAutomationPeer;
if(lvpeer != null)
{
foreach (UIElement e in _owner.HeaderRowPresenter.ActualColumnHeaders)
{
AutomationPeer peer = UIElementAutomationPeer.CreatePeerForElement(e);
if (peer != null)
{
array.Add(ElementProxy.StaticWrap(peer, lvpeer));
}
}
}
return array.ToArray();
}
return new IRawElementProviderSimple[0] ;
}
/// <summary>
/// Collection of row headers
/// </summary>
IRawElementProviderSimple[] ITableProvider.GetRowHeaders()
{
//If there are no row headers, return an empty array
return new IRawElementProviderSimple[0];
}
#endregion
#region IGridProvider
/// <summary>
/// number of columns in the grid
/// </summary>
int IGridProvider.ColumnCount
{
get
{
if (_owner.HeaderRowPresenter != null)
{
return _owner.HeaderRowPresenter.ActualColumnHeaders.Count;
}
return _owner.Columns.Count;
}
}
/// <summary>
/// number of rows in the grid
/// </summary>
int IGridProvider.RowCount
{
get { return _listview.Items.Count; }
}
/// <summary>
/// Obtain the IRawElementProviderSimple at an absolute position
/// </summary>
IRawElementProviderSimple IGridProvider.GetItem(int row, int column)
{
if (row < 0 || row >= ((IGridProvider)this).RowCount)
{
throw new ArgumentOutOfRangeException("row");
}
if (column < 0 || column >= ((IGridProvider)this).ColumnCount)
{
throw new ArgumentOutOfRangeException("column");
}
ListViewItem lvi = _listview.ItemContainerGenerator.ContainerFromIndex(row) as ListViewItem;
//If item is virtualized, try to de-virtualize it
if (lvi == null)
{
VirtualizingPanel itemsHost = _listview.ItemsHost as VirtualizingPanel;
if (itemsHost != null)
{
itemsHost.BringIndexIntoView(row);
}
lvi = _listview.ItemContainerGenerator.ContainerFromIndex(row) as ListViewItem;
if (lvi != null)
{
//Must call Invoke here to force run the render process
_listview.Dispatcher.Invoke(
System.Windows.Threading.DispatcherPriority.Loaded,
(System.Windows.Threading.DispatcherOperationCallback)delegate(object arg)
{
return null;
},
null);
}
}
//lvi is null, it is virtualized, so we can't return its cell
if (lvi != null)
{
AutomationPeer lvpeer = UIElementAutomationPeer.FromElement(_listview);
if(lvpeer != null)
{
AutomationPeer peer = UIElementAutomationPeer.FromElement(lvi);
if (peer != null)
{
// use the GridViewItemAutomationPeer, if available
AutomationPeer eventSource = peer.EventsSource;
if (eventSource != null)
{
peer = eventSource;
}
List<AutomationPeer> columns = peer.GetChildren();
if (columns.Count > column)
{
return ElementProxy.StaticWrap(columns[column], lvpeer);
}
}
}
}
return null;
}
/// <summary>
/// Fire ColumnCount changed event for GridPattern
/// </summary>
private void OnColumnCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
if (_oldColumnsCount != _owner.Columns.Count)
{
ListViewAutomationPeer peer = UIElementAutomationPeer.FromElement(_listview) as ListViewAutomationPeer;
Invariant.Assert(peer != null);
if (peer != null)
{
peer.RaisePropertyChangedEvent(GridPatternIdentifiers.ColumnCountProperty, _oldColumnsCount, _owner.Columns.Count);
}
}
_oldColumnsCount = _owner.Columns.Count;
AutomationPeer lvPeer = UIElementAutomationPeer.FromElement(_listview);
if (lvPeer != null)
{
List<AutomationPeer> list = lvPeer.GetChildren();
if (list != null)
{
foreach (AutomationPeer peer in list)
{
peer.InvalidatePeer();
}
}
}
}
#endregion
#region Helper
internal static Visual FindVisualByType(Visual parent, Type type)
{
if (parent != null)
{
int count = parent.InternalVisualChildrenCount;
for (int i = 0; i < count; i++)
{
Visual visual = parent.InternalGetVisualChild(i);
if (!type.IsInstanceOfType(visual))
{
visual = FindVisualByType(visual, type);
}
if (visual != null)
{
return visual;
}
}
}
return null;
}
#endregion
#region Private Fields
private GridView _owner;
private ListView _listview;
//Store the old items/columns count, this is used for firing RowCount changed event in IGridProvider
private int _oldItemsCount = 0;
private int _oldColumnsCount = 0;
#endregion
}
}
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