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//---------------------------------------------------------------------------
//
// Copyright (C) Microsoft Corporation. All rights reserved.
//
//---------------------------------------------------------------------------
using System.Collections.Specialized;
using System.Windows.Automation.Peers; // OnCreateAutomationPeer
using MS.Internal.Telemetry.PresentationFramework;
namespace System.Windows.Controls
{
/// <summary>
/// A general purpose control for data presentation as part of the set of common controls provided with Avalon.
/// Drop a control into a layout;
/// Enable application developers to display data efficiently;
/// Allow the presentation of data to be styled, including the layout and the item visuals;
/// No type-specific functionality.
///
/// ListView is a control which has
/// A data collection;
/// A set of predefined operations to manipulate the data/view.
/// Also, ListView is a control for the most convenient browsing of data.
/// </summary>
#if OLD_AUTOMATION
[Automation(AccessibilityControlType = "List")]
#endif
[StyleTypedProperty(Property = "ItemContainerStyle", StyleTargetType = typeof(ListViewItem))]
public class ListView : ListBox
{
//-------------------------------------------------------------------
//
// Constructors
//
//-------------------------------------------------------------------
#region Constructors
static ListView()
{
SelectionModeProperty.OverrideMetadata(typeof(ListView), new FrameworkPropertyMetadata(SelectionMode.Extended));
ControlsTraceLogger.AddControl(TelemetryControls.ListView);
}
#endregion Constructors
//-------------------------------------------------------------------
//
// Public Methods
//
//-------------------------------------------------------------------
//-------------------------------------------------------------------
//
// Public Properties
//
//-------------------------------------------------------------------
#region Public Properties
/// <summary>
/// View DependencyProperty
/// </summary>
public static readonly DependencyProperty ViewProperty =
DependencyProperty.Register(
"View",
typeof(ViewBase),
typeof(ListView),
new PropertyMetadata(
new PropertyChangedCallback(OnViewChanged))
);
/// <summary>
/// descriptor of the whole view. Include chrome/layout/item/...
/// </summary>
public ViewBase View
{
get { return (ViewBase)GetValue(ViewProperty); }
set { SetValue(ViewProperty, value); }
}
private static void OnViewChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
ListView listView = (ListView)d;
ViewBase oldView = (ViewBase)e.OldValue;
ViewBase newView = (ViewBase)e.NewValue;
if (newView != null)
{
if (newView.IsUsed)
{
throw new InvalidOperationException(SR.Get(SRID.ListView_ViewCannotBeShared));
}
newView.IsUsed = true;
}
// In ApplyNewView ListView.ClearContainerForItemOverride will be called for each item.
// Should use old view to do clear item.
listView._previousView = oldView;
listView.ApplyNewView();
// After ApplyNewView, if item is removed, ListView.ClearContainerForItemOverride will be called.
// Then should use new view to do clear item.
listView._previousView = newView;
//Switch ViewAutomationPeer in ListViewAutomationPeer
ListViewAutomationPeer lvPeer = UIElementAutomationPeer.FromElement(listView) as ListViewAutomationPeer;
if (lvPeer != null)
{
if (lvPeer.ViewAutomationPeer != null)
{
lvPeer.ViewAutomationPeer.ViewDetached();
}
if (newView != null)
{
lvPeer.ViewAutomationPeer = newView.GetAutomationPeer(listView);
}
else
{
lvPeer.ViewAutomationPeer = null;
}
//Invalidate the ListView automation tree because the view has been changed
lvPeer.InvalidatePeer();
}
if (oldView != null)
{
oldView.IsUsed = false;
}
}
#endregion
//-------------------------------------------------------------------
//
// Protected Methods
//
//-------------------------------------------------------------------
#region Protected Methods
/// <summary>
/// Prepare the element to display the item. Override the default style
/// if new view is a GridView and no ItemContainerStyle provided.
/// Will call View.PrepareItem() to allow view do preparison for item.
/// </summary>
protected override void PrepareContainerForItemOverride(DependencyObject element, object item)
{
base.PrepareContainerForItemOverride(element, item);
ListViewItem lvi = element as ListViewItem;
if (lvi != null)
{
ViewBase view = View;
if (view != null)
{
// update default style key
lvi.SetDefaultStyleKey(view.ItemContainerDefaultStyleKey);
view.PrepareItem(lvi);
}
else
{
lvi.ClearDefaultStyleKey();
}
}
}
/// <summary>
/// Clear the element to display the item.
/// </summary>
protected override void ClearContainerForItemOverride(DependencyObject element, object item)
{
// This method no longer does the work it used to (bug 1445288).
// It is called when a container is removed from the tree; such a
// container will be GC'd soon, so there's no point in changing
// its properties.
base.ClearContainerForItemOverride(element, item);
}
/// <summary> Return true if the item is (or is eligible to be) its own ItemContainer </summary>
protected override bool IsItemItsOwnContainerOverride(object item)
{
return (item is ListViewItem);
}
/// <summary> Create or identify the element used to display the given item. </summary>
protected override DependencyObject GetContainerForItemOverride()
{
return new ListViewItem();
}
/// <summary>
///
/// </summary>
/// <param name="e"></param>
protected override void OnItemsChanged(NotifyCollectionChangedEventArgs e)
{
base.OnItemsChanged(e);
ListViewAutomationPeer lvPeer = UIElementAutomationPeer.FromElement(this) as ListViewAutomationPeer;
if (lvPeer != null && lvPeer.ViewAutomationPeer != null)
{
lvPeer.ViewAutomationPeer.ItemsChanged(e);
}
}
#endregion // Protected Methods
//-------------------------------------------------------------------
//
// Accessibility
//
//-------------------------------------------------------------------
#region Accessibility
/// <summary>
/// Creates AutomationPeer (<see cref="UIElement.OnCreateAutomationPeer"/>)
/// </summary>
protected override AutomationPeer OnCreateAutomationPeer()
{
ListViewAutomationPeer lvPeer = new ListViewAutomationPeer(this);
if (lvPeer != null && View != null)
{
lvPeer.ViewAutomationPeer = View.GetAutomationPeer(this);
}
return lvPeer;
}
#endregion
//-------------------------------------------------------------------
//
// Private Methods
//
//-------------------------------------------------------------------
#region Private Methods
// apply styles described in View.
private void ApplyNewView()
{
ViewBase newView = View;
if (newView != null)
{
// update default style key of ListView
DefaultStyleKey = newView.DefaultStyleKey;
}
else
{
ClearValue(DefaultStyleKeyProperty);
}
// Encounter a new view after loaded means user is switching view.
// Force to regenerate all containers.
if (IsLoaded)
{
ItemContainerGenerator.Refresh();
}
}
// Invalidate resources on the view header if the header isn't
// reachable via the visual/logical tree
internal override void OnThemeChanged()
{
// If the ListView does not have a template generated tree then its
// View.Header is not reachable via a tree walk.
if (!HasTemplateGeneratedSubTree && View != null)
{
View.OnThemeChanged();
}
}
#endregion Private Methods
//-------------------------------------------------------------------
//
// Private Fields
//
//-------------------------------------------------------------------
private ViewBase _previousView;
}
}
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