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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
using MS.Internal;
using MS.Internal.KnownBoxes;
using MS.Utility;
using System.ComponentModel;
using System.Diagnostics;
using System.Windows.Threading;
using System.Windows.Automation;
using System.Windows.Automation.Peers;
using System.Windows.Media;
using System.Windows.Input;
using System.Windows.Controls.Primitives;
using System.Windows.Shapes;
using System;
// Disable CS3001: Warning as Error: not CLS-compliant
#pragma warning disable 3001
namespace System.Windows.Controls
{
/// <summary>
/// Control that implements a selectable item inside a ListBox.
/// </summary>
[DefaultEvent("Selected")]
public class ListBoxItem : ContentControl
{
//-------------------------------------------------------------------
//
// Constructors
//
//-------------------------------------------------------------------
#region Constructors
/// <summary>
/// Default DependencyObject constructor
/// </summary>
public ListBoxItem() : base()
{
}
static ListBoxItem()
{
DefaultStyleKeyProperty.OverrideMetadata(typeof(ListBoxItem), new FrameworkPropertyMetadata(typeof(ListBoxItem)));
_dType = DependencyObjectType.FromSystemTypeInternal(typeof(ListBoxItem));
KeyboardNavigation.DirectionalNavigationProperty.OverrideMetadata(typeof(ListBoxItem), new FrameworkPropertyMetadata(KeyboardNavigationMode.Once));
KeyboardNavigation.TabNavigationProperty.OverrideMetadata(typeof(ListBoxItem), new FrameworkPropertyMetadata(KeyboardNavigationMode.Local));
IsEnabledProperty.OverrideMetadata(typeof(ListBoxItem), new UIPropertyMetadata(new PropertyChangedCallback(OnVisualStatePropertyChanged)));
IsMouseOverPropertyKey.OverrideMetadata(typeof(ListBoxItem), new UIPropertyMetadata(new PropertyChangedCallback(OnVisualStatePropertyChanged)));
Selector.IsSelectionActivePropertyKey.OverrideMetadata(typeof(ListBoxItem), new FrameworkPropertyMetadata(new PropertyChangedCallback(OnVisualStatePropertyChanged)));
AutomationProperties.IsOffscreenBehaviorProperty.OverrideMetadata(typeof(ListBoxItem), new FrameworkPropertyMetadata(IsOffscreenBehavior.FromClip));
}
#endregion
//-------------------------------------------------------------------
//
// Public Properties
//
//-------------------------------------------------------------------
#region Public Properties
/// <summary>
/// Indicates whether this ListBoxItem is selected.
/// </summary>
public static readonly DependencyProperty IsSelectedProperty =
Selector.IsSelectedProperty.AddOwner(typeof(ListBoxItem),
new FrameworkPropertyMetadata(BooleanBoxes.FalseBox,
FrameworkPropertyMetadataOptions.BindsTwoWayByDefault | FrameworkPropertyMetadataOptions.Journal,
new PropertyChangedCallback(OnIsSelectedChanged)));
/// <summary>
/// Indicates whether this ListBoxItem is selected.
/// </summary>
[Bindable(true), Category("Appearance")]
public bool IsSelected
{
get { return (bool) GetValue(IsSelectedProperty); }
set { SetValue(IsSelectedProperty, BooleanBoxes.Box(value)); }
}
private static void OnIsSelectedChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
ListBoxItem listItem = d as ListBoxItem;
bool isSelected = (bool) e.NewValue;
Selector parentSelector = listItem.ParentSelector;
if (parentSelector != null)
{
parentSelector.RaiseIsSelectedChangedAutomationEvent(listItem, isSelected);
}
if (isSelected)
{
listItem.OnSelected(new RoutedEventArgs(Selector.SelectedEvent, listItem));
}
else
{
listItem.OnUnselected(new RoutedEventArgs(Selector.UnselectedEvent, listItem));
}
listItem.UpdateVisualState();
}
/// <summary>
/// Event indicating that the IsSelected property is now true.
/// </summary>
/// <param name="e">Event arguments</param>
protected virtual void OnSelected(RoutedEventArgs e)
{
HandleIsSelectedChanged(true, e);
}
/// <summary>
/// Event indicating that the IsSelected property is now false.
/// </summary>
/// <param name="e">Event arguments</param>
protected virtual void OnUnselected(RoutedEventArgs e)
{
HandleIsSelectedChanged(false, e);
}
private void HandleIsSelectedChanged(bool newValue, RoutedEventArgs e)
{
RaiseEvent(e);
}
#endregion
#region Events
/// <summary>
/// Raised when the item's IsSelected property becomes true.
/// </summary>
public static readonly RoutedEvent SelectedEvent = Selector.SelectedEvent.AddOwner(typeof(ListBoxItem));
/// <summary>
/// Raised when the item's IsSelected property becomes true.
/// </summary>
public event RoutedEventHandler Selected
{
add
{
AddHandler(SelectedEvent, value);
}
remove
{
RemoveHandler(SelectedEvent, value);
}
}
/// <summary>
/// Raised when the item's IsSelected property becomes false.
/// </summary>
public static readonly RoutedEvent UnselectedEvent = Selector.UnselectedEvent.AddOwner(typeof(ListBoxItem));
/// <summary>
/// Raised when the item's IsSelected property becomes false.
/// </summary>
public event RoutedEventHandler Unselected
{
add
{
AddHandler(UnselectedEvent, value);
}
remove
{
RemoveHandler(UnselectedEvent, value);
}
}
#endregion
//-------------------------------------------------------------------
//
// Protected Methods
//
//-------------------------------------------------------------------
#region Protected Methods
internal override void ChangeVisualState(bool useTransitions)
{
// Change to the correct state in the Interaction group
if (!IsEnabled)
{
// [copied from SL code]
// If our child is a control then we depend on it displaying a proper "disabled" state. If it is not a control
// (ie TextBlock, Border, etc) then we will use our visuals to show a disabled state.
VisualStateManager.GoToState(this, Content is Control ? VisualStates.StateNormal : VisualStates.StateDisabled, useTransitions);
}
else if (IsMouseOver)
{
VisualStateManager.GoToState(this, VisualStates.StateMouseOver, useTransitions);
}
else
{
VisualStateManager.GoToState(this, VisualStates.StateNormal, useTransitions);
}
// Change to the correct state in the Selection group
if (IsSelected)
{
if (Selector.GetIsSelectionActive(this))
{
VisualStateManager.GoToState(this, VisualStates.StateSelected, useTransitions);
}
else
{
VisualStates.GoToState(this, useTransitions, VisualStates.StateSelectedUnfocused, VisualStates.StateSelected);
}
}
else
{
VisualStateManager.GoToState(this, VisualStates.StateUnselected, useTransitions);
}
if (IsKeyboardFocused)
{
VisualStateManager.GoToState(this, VisualStates.StateFocused, useTransitions);
}
else
{
VisualStateManager.GoToState(this, VisualStates.StateUnfocused, useTransitions);
}
base.ChangeVisualState(useTransitions);
}
/// <summary>
/// Creates AutomationPeer (<see cref="UIElement.OnCreateAutomationPeer"/>)
/// </summary>
protected override AutomationPeer OnCreateAutomationPeer()
{
return new ListBoxItemWrapperAutomationPeer(this);
}
/// <summary>
/// This is the method that responds to the MouseButtonEvent event.
/// </summary>
/// <param name="e">Event arguments</param>
protected override void OnMouseLeftButtonDown(MouseButtonEventArgs e)
{
if (!e.Handled)
{
// turn this into a Selector.ItemClicked thing?
e.Handled = true;
HandleMouseButtonDown(MouseButton.Left);
}
base.OnMouseLeftButtonDown(e);
}
/// <summary>
/// This is the method that responds to the MouseButtonEvent event.
/// </summary>
/// <param name="e">Event arguments</param>
protected override void OnMouseRightButtonDown(MouseButtonEventArgs e)
{
if (!e.Handled)
{
// turn this into a Selector.ItemClicked thing?
e.Handled = true;
HandleMouseButtonDown(MouseButton.Right);
}
base.OnMouseRightButtonDown(e);
}
private void HandleMouseButtonDown(MouseButton mouseButton)
{
if (Selector.UiGetIsSelectable(this) && Focus())
{
ListBox parent = ParentListBox;
if (parent != null)
{
parent.NotifyListItemClicked(this, mouseButton);
}
}
}
/// <summary>
/// Called when IsMouseOver changes on this element.
/// </summary>
/// <param name="e"></param>
protected override void OnMouseEnter(MouseEventArgs e)
{
// abort any drag operation we have queued.
if (parentNotifyDraggedOperation != null)
{
parentNotifyDraggedOperation.Abort();
parentNotifyDraggedOperation = null;
}
if (IsMouseOver)
{
ListBox parent = ParentListBox;
if (parent != null && Mouse.LeftButton == MouseButtonState.Pressed)
{
parent.NotifyListItemMouseDragged(this);
}
}
base.OnMouseEnter(e);
}
/// <summary>
/// Called when IsMouseOver changes on this element.
/// </summary>
/// <param name="e"></param>
protected override void OnMouseLeave(MouseEventArgs e)
{
// abort any drag operation we have queued.
if (parentNotifyDraggedOperation != null)
{
parentNotifyDraggedOperation.Abort();
parentNotifyDraggedOperation = null;
}
base.OnMouseLeave(e);
}
/// <summary>
/// Called when the visual parent of this element changes.
/// </summary>
/// <param name="oldParent"></param>
protected internal override void OnVisualParentChanged(DependencyObject oldParent)
{
ItemsControl oldItemsControl = null;
if (VisualTreeHelper.GetParent(this) == null)
{
if (IsKeyboardFocusWithin)
{
// This ListBoxItem had focus but was removed from the tree.
// The normal behavior is for focus to become null, but we would rather that
// focus go to the parent ListBox.
// Use the oldParent to get a reference to the ListBox that this ListBoxItem used to be in.
// The oldParent's ItemsOwner should be the ListBox.
oldItemsControl = ItemsControl.GetItemsOwner(oldParent);
}
}
base.OnVisualParentChanged(oldParent);
// If earlier, we decided to set focus to the old parent ListBox, do it here
// after calling base so that the state for IsKeyboardFocusWithin is updated correctly.
if (oldItemsControl != null)
{
oldItemsControl.Focus();
}
}
#endregion
//-------------------------------------------------------------------
//
// Implementation
//
//-------------------------------------------------------------------
#region Implementation
private ListBox ParentListBox
{
get
{
return ParentSelector as ListBox;
}
}
internal Selector ParentSelector
{
get
{
return ItemsControl.ItemsControlFromItemContainer(this) as Selector;
}
}
#endregion
#if OLD_AUTOMATION
// left here for reference only as it is still used by MonthCalendar
/// <summary>
/// DependencyProperty for SelectionContainer property.
/// </summary>
internal static readonly DependencyProperty SelectionContainerProperty
= DependencyProperty.RegisterAttached("SelectionContainer", typeof(UIElement), typeof(ListBoxItem),
new FrameworkPropertyMetadata((UIElement)null));
#endif
#region Private Fields
DispatcherOperation parentNotifyDraggedOperation = null;
#endregion
#region DTypeThemeStyleKey
// Returns the DependencyObjectType for the registered ThemeStyleKey's default
// value. Controls will override this method to return approriate types.
internal override DependencyObjectType DTypeThemeStyleKey
{
get { return _dType; }
}
private static DependencyObjectType _dType;
#endregion DTypeThemeStyleKey
}
}
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