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//---------------------------------------------------------------------------
//
// Copyright (C) Microsoft Corporation. All rights reserved.
//
//---------------------------------------------------------------------------
using System.Diagnostics; // Debug
using System.Windows.Automation.Peers; // IViewAutomationPeer
namespace System.Windows.Controls
{
/// <summary>
/// ViewBase is something that tells the ListView the way to present each
/// entity in the data collection, i.e. the default style key.
/// </summary>
public abstract class ViewBase : DependencyObject
{
#region Protected Methods
/// <summary>
/// called when ListView is prepare container for item
/// </summary>
/// <param name="item">the container</param>
protected internal virtual void PrepareItem(ListViewItem item)
{
}
/// <summary>
/// called when ListView is clear container for item
/// </summary>
/// <param name="item">the container</param>
protected internal virtual void ClearItem(ListViewItem item)
{
}
/// <summary>
/// default style key.
/// ListView will degrate to ListBox if sub-class doesn't override
/// this value.
/// </summary>
protected internal virtual object DefaultStyleKey
{
get { return typeof(ListBox); }
}
/// <summary>
/// default container style key
/// The container, ListViewItem, will degrate to ListBoxItem if
/// sub-class doesn't override this value.
/// </summary>
protected internal virtual object ItemContainerDefaultStyleKey
{
get { return typeof(ListBoxItem); }
}
// Propagate theme changes to contained headers
internal virtual void OnThemeChanged()
{
}
#endregion
#region InheritanceContext
/// <summary>
/// InheritanceContext
/// </summary>
internal override DependencyObject InheritanceContext
{
get { return _inheritanceContext; }
}
// Receive a new inheritance context
internal override void AddInheritanceContext(DependencyObject context, DependencyProperty property)
{
if (_inheritanceContext != context)
{
// Pick up the new context
_inheritanceContext = context;
OnInheritanceContextChanged(EventArgs.Empty);
}
}
// Remove an inheritance context
internal override void RemoveInheritanceContext(DependencyObject context, DependencyProperty property)
{
if (_inheritanceContext == context)
{
// clear the context
_inheritanceContext = null;
OnInheritanceContextChanged(EventArgs.Empty);
}
}
// Fields to implement DO's inheritance context
DependencyObject _inheritanceContext;
#endregion InheritanceContext
/// <summary>
/// called when ListView creates its Automation peer
/// </summary>
/// <param name="parent">listview reference</param>
/// <returns>IViewAutomationPeer</returns>
/// <remarks>ListView will use this method to get an automationPeer for a given view
/// and default to the properties/patterns implemented by the view before going to
/// default fall-backs on ListView.</remarks>
internal protected virtual IViewAutomationPeer GetAutomationPeer(ListView parent)
{
return null;
}
// True, when view is assigned to a ListView.
internal bool IsUsed
{
get { return _isUsed; }
set { _isUsed = value; }
}
private bool _isUsed;
}
}
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