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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 System.ComponentModel;
using System.Windows.Threading;
using System.Windows.Automation.Peers;
using MS.Internal.KnownBoxes;
// Disable CS3001: Warning as Error: not CLS-compliant
#pragma warning disable 3001
namespace System.Windows.Controls.Primitives
{
/// <summary>
/// ToggleButton
/// </summary>
[DefaultEvent("Checked")]
public class ToggleButton : ButtonBase
{
#region Constructors
static ToggleButton()
{
DefaultStyleKeyProperty.OverrideMetadata(typeof(ToggleButton), new FrameworkPropertyMetadata(typeof(ToggleButton)));
_dType = DependencyObjectType.FromSystemTypeInternal(typeof(ToggleButton));
}
/// <summary>
/// Default ToggleButton constructor
/// </summary>
/// <remarks>
/// Automatic determination of current Dispatcher. Use alternative constructor
/// that accepts a Dispatcher for best performance.
/// </remarks>
public ToggleButton() : base()
{
}
#endregion
#region Properties and Events
/// <summary>
/// Checked event
/// </summary>
public static readonly RoutedEvent CheckedEvent = EventManager.RegisterRoutedEvent("Checked", RoutingStrategy.Bubble, typeof(RoutedEventHandler), typeof(ToggleButton));
/// <summary>
/// Unchecked event
/// </summary>
public static readonly RoutedEvent UncheckedEvent = EventManager.RegisterRoutedEvent("Unchecked", RoutingStrategy.Bubble, typeof(RoutedEventHandler), typeof(ToggleButton));
/// <summary>
/// Indeterminate event
/// </summary>
public static readonly RoutedEvent IndeterminateEvent = EventManager.RegisterRoutedEvent("Indeterminate", RoutingStrategy.Bubble, typeof(RoutedEventHandler), typeof(ToggleButton));
/// <summary>
/// Add / Remove Checked handler
/// </summary>
[Category("Behavior")]
public event RoutedEventHandler Checked
{
add
{
AddHandler(CheckedEvent, value);
}
remove
{
RemoveHandler(CheckedEvent, value);
}
}
/// <summary>
/// Add / Remove Unchecked handler
/// </summary>
[Category("Behavior")]
public event RoutedEventHandler Unchecked
{
add
{
AddHandler(UncheckedEvent, value);
}
remove
{
RemoveHandler(UncheckedEvent, value);
}
}
/// <summary>
/// Add / Remove Indeterminate handler
/// </summary>
[Category("Behavior")]
public event RoutedEventHandler Indeterminate
{
add
{
AddHandler(IndeterminateEvent, value);
}
remove
{
RemoveHandler(IndeterminateEvent, value);
}
}
/// <summary>
/// The DependencyProperty for the IsChecked property.
/// Flags: BindsTwoWayByDefault
/// Default Value: false
/// </summary>
public static readonly DependencyProperty IsCheckedProperty =
DependencyProperty.Register(
"IsChecked",
typeof(bool?),
typeof(ToggleButton),
new FrameworkPropertyMetadata(
BooleanBoxes.FalseBox,
FrameworkPropertyMetadataOptions.BindsTwoWayByDefault | FrameworkPropertyMetadataOptions.Journal,
new PropertyChangedCallback(OnIsCheckedChanged)));
/// <summary>
/// Indicates whether the ToggleButton is checked
/// </summary>
[Category("Appearance")]
[TypeConverter(typeof(NullableBoolConverter))]
[Localizability(LocalizationCategory.None, Readability = Readability.Unreadable)]
public bool? IsChecked
{
get
{
// Because Nullable<bool> unboxing is very slow (uses reflection) first we cast to bool
object value = GetValue(IsCheckedProperty);
if (value == null)
return new Nullable<bool>();
else
return new Nullable<bool>((bool)value);
}
set
{
SetValue(IsCheckedProperty, value.HasValue ? BooleanBoxes.Box(value.Value) : null);
}
}
private static object OnGetIsChecked(DependencyObject d) {return ((ToggleButton)d).IsChecked;}
/// <summary>
/// Called when IsChecked is changed on "d."
/// </summary>
/// <param name="d">The object on which the property was changed.</param>
/// <param name="e">EventArgs that contains the old and new values for this property</param>
private static void OnIsCheckedChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
ToggleButton button = (ToggleButton)d;
bool? oldValue = (bool?) e.OldValue;
bool? newValue = (bool?) e.NewValue;
//doing soft casting here because the peer can be that of RadioButton and it is not derived from
//ToggleButtonAutomationPeer - specifically to avoid implementing TogglePattern
ToggleButtonAutomationPeer peer = UIElementAutomationPeer.FromElement(button) as ToggleButtonAutomationPeer;
if (peer != null)
{
peer.RaiseToggleStatePropertyChangedEvent(oldValue, newValue);
}
if (newValue == true)
{
button.OnChecked(new RoutedEventArgs(CheckedEvent));
}
else if (newValue == false)
{
button.OnUnchecked(new RoutedEventArgs(UncheckedEvent));
}
else
{
button.OnIndeterminate(new RoutedEventArgs(IndeterminateEvent));
}
button.UpdateVisualState();
}
/// <summary>
/// Called when IsChecked becomes true.
/// </summary>
/// <param name="e">Event arguments for the routed event that is raised by the default implementation of this method.</param>
protected virtual void OnChecked(RoutedEventArgs e)
{
RaiseEvent(e);
}
/// <summary>
/// Called when IsChecked becomes false.
/// </summary>
/// <param name="e">Event arguments for the routed event that is raised by the default implementation of this method.</param>
protected virtual void OnUnchecked(RoutedEventArgs e)
{
RaiseEvent(e);
}
/// <summary>
/// Called when IsChecked becomes null.
/// </summary>
/// <param name="e">Event arguments for the routed event that is raised by the default implementation of this method.</param>
protected virtual void OnIndeterminate(RoutedEventArgs e)
{
RaiseEvent(e);
}
/// <summary>
/// The DependencyProperty for the IsThreeState property.
/// Flags: None
/// Default Value: false
/// </summary>
public static readonly DependencyProperty IsThreeStateProperty =
DependencyProperty.Register(
"IsThreeState",
typeof(bool),
typeof(ToggleButton),
new FrameworkPropertyMetadata(BooleanBoxes.FalseBox));
/// <summary>
/// The IsThreeState property determines whether the control supports two or three states.
/// IsChecked property can be set to null as a third state when IsThreeState is true
/// </summary>
[Bindable(true), Category("Behavior")]
public bool IsThreeState
{
get { return (bool) GetValue(IsThreeStateProperty); }
set { SetValue(IsThreeStateProperty, BooleanBoxes.Box(value)); }
}
#endregion
#region Override methods
/// <summary>
/// Creates AutomationPeer (<see cref="UIElement.OnCreateAutomationPeer"/>)
/// </summary>
protected override AutomationPeer OnCreateAutomationPeer()
{
return new ToggleButtonAutomationPeer(this);
}
/// <summary>
/// This override method is called when the control is clicked by mouse or keyboard
/// </summary>
protected override void OnClick()
{
OnToggle();
base.OnClick();
}
#endregion
#region Method Overrides
internal override void ChangeVisualState(bool useTransitions)
{
base.ChangeVisualState(useTransitions);
// Update the Check state group
var isChecked = IsChecked;
if (isChecked == true)
{
VisualStateManager.GoToState(this, VisualStates.StateChecked, useTransitions);
}
else if (isChecked == false)
{
VisualStateManager.GoToState(this, VisualStates.StateUnchecked, useTransitions);
}
else
{
// isChecked is null
VisualStates.GoToState(this, useTransitions, VisualStates.StateIndeterminate, VisualStates.StateUnchecked);
}
}
/// <summary>
/// Gives a string representation of this object.
/// </summary>
public override string ToString()
{
string typeText = this.GetType().ToString();
string contentText = String.Empty;
bool? isChecked = false;
bool valuesDefined = false;
// Accessing ToggleButton properties may be thread sensitive
if (CheckAccess())
{
contentText = GetPlainText();
isChecked = IsChecked;
valuesDefined = true;
}
else
{
//Not on dispatcher, try posting to the dispatcher with 20ms timeout
Dispatcher.Invoke(DispatcherPriority.Send, new TimeSpan(0, 0, 0, 0, 20), new DispatcherOperationCallback(delegate(object o)
{
contentText = GetPlainText();
isChecked = IsChecked;
valuesDefined = true;
return null;
}), null);
}
// If Content and isChecked are defined
if (valuesDefined)
{
return SR.Format(SR.ToStringFormatString_ToggleButton, typeText, contentText, isChecked.HasValue ? isChecked.Value.ToString() : "null");
}
// Not able to access the dispatcher
return typeText;
}
#endregion
#region Protected virtual methods
/// <summary>
/// This vitrual method is called from OnClick(). ToggleButton toggles IsChecked property.
/// Subclasses can override this method to implement their own toggle behavior
/// </summary>
protected internal virtual void OnToggle()
{
// If IsChecked == true && IsThreeState == true ---> IsChecked = null
// If IsChecked == true && IsThreeState == false ---> IsChecked = false
// If IsChecked == false ---> IsChecked = true
// If IsChecked == null ---> IsChecked = false
bool? isChecked;
if (IsChecked == true)
isChecked = IsThreeState ? (bool?)null : (bool?)false;
else // false or null
isChecked = IsChecked.HasValue; // HasValue returns true if IsChecked==false
SetCurrentValueInternal(IsCheckedProperty, isChecked);
}
#endregion
#region Data
#endregion
#region Accessibility
#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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