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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;
namespace System.Windows.Controls.Primitives
{
/// <summary>
/// The RangeBase class is the base class from which all "range-like"
/// controls derive. It defines the relevant events and properties, as
/// well as providing handlers for the relevant input events.
/// </summary>
/// <ExternalAPI/>
[DefaultEvent("ValueChanged"), DefaultProperty("Value")]
public abstract class RangeBase : Control
{
#region Constructors
/// <summary>
/// This is the static constructor for the RangeBase class. It
/// hooks the changed notifications needed for visual state changes.
/// </summary>
static RangeBase()
{
IsEnabledProperty.OverrideMetadata(typeof(RangeBase), new UIPropertyMetadata(new PropertyChangedCallback(OnVisualStatePropertyChanged)));
IsMouseOverPropertyKey.OverrideMetadata(typeof(RangeBase), new UIPropertyMetadata(new PropertyChangedCallback(OnVisualStatePropertyChanged)));
}
/// <summary>
/// Default RangeBase constructor
/// </summary>
/// <remarks>
/// Automatic determination of current Dispatcher. Use alternative constructor
/// that accepts a Dispatcher for best performance.
/// </remarks>
protected RangeBase()
{
}
#endregion Constructors
#region Events
/// <summary>
/// Event correspond to Value changed event
/// </summary>
public static readonly RoutedEvent ValueChangedEvent = EventManager.RegisterRoutedEvent("ValueChanged", RoutingStrategy.Bubble, typeof(RoutedPropertyChangedEventHandler<double>), typeof(RangeBase));
/// <summary>
/// Add / Remove ValueChangedEvent handler
/// </summary>
[Category("Behavior")]
public event RoutedPropertyChangedEventHandler<double> ValueChanged { add { AddHandler(ValueChangedEvent, value); } remove { RemoveHandler(ValueChangedEvent, value); } }
#endregion Events
#region Properties
/// <summary>
/// The DependencyProperty for the Minimum property.
/// Flags: none
/// Default Value: 0
/// </summary>
public static readonly DependencyProperty MinimumProperty =
DependencyProperty.Register(
"Minimum",
typeof(double),
typeof(RangeBase),
new FrameworkPropertyMetadata(
0.0d,
new PropertyChangedCallback(OnMinimumChanged)),
new ValidateValueCallback(IsValidDoubleValue));
/// <summary>
/// Minimum restricts the minimum value of the Value property
/// </summary>
[Bindable(true), Category("Behavior")]
public double Minimum
{
get { return (double) GetValue(MinimumProperty); }
set { SetValue(MinimumProperty, value); }
}
/// <summary>
/// Called when MinimumProperty is changed on "d."
/// </summary>
private static void OnMinimumChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
RangeBase ctrl = (RangeBase) d;
RangeBaseAutomationPeer peer = UIElementAutomationPeer.FromElement(ctrl) as RangeBaseAutomationPeer;
if (peer != null)
{
peer.RaiseMinimumPropertyChangedEvent((double)e.OldValue, (double)e.NewValue);
}
ctrl.CoerceValue(MaximumProperty);
ctrl.CoerceValue(ValueProperty);
ctrl.OnMinimumChanged((double)e.OldValue, (double)e.NewValue);
}
/// <summary>
/// This method is invoked when the Minimum property changes.
/// </summary>
/// <param name="oldMinimum">The old value of the Minimum property.</param>
/// <param name="newMinimum">The new value of the Minimum property.</param>
protected virtual void OnMinimumChanged(double oldMinimum, double newMinimum)
{
}
/// <summary>
/// The DependencyProperty for the Maximum property.
/// Flags: none
/// Default Value: 1
/// </summary>
public static readonly DependencyProperty MaximumProperty =
DependencyProperty.Register(
"Maximum",
typeof(double),
typeof(RangeBase),
new FrameworkPropertyMetadata(
1.0d,
new PropertyChangedCallback(OnMaximumChanged),
new CoerceValueCallback(CoerceMaximum)),
new ValidateValueCallback(IsValidDoubleValue));
private static object CoerceMaximum(DependencyObject d, object value)
{
RangeBase ctrl = (RangeBase) d;
double min = ctrl.Minimum;
if ((double) value < min)
{
return min;
}
return value;
}
/// <summary>
/// Maximum restricts the maximum value of the Value property
/// </summary>
[Bindable(true), Category("Behavior")]
public double Maximum
{
get { return (double) GetValue(MaximumProperty); }
set { SetValue(MaximumProperty, value); }
}
/// <summary>
/// Called when MaximumProperty is changed on "d."
/// </summary>
private static void OnMaximumChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
RangeBase ctrl = (RangeBase) d;
RangeBaseAutomationPeer peer = UIElementAutomationPeer.FromElement(ctrl) as RangeBaseAutomationPeer;
if (peer != null)
{
peer.RaiseMaximumPropertyChangedEvent((double)e.OldValue, (double)e.NewValue);
}
ctrl.CoerceValue(ValueProperty);
ctrl.OnMaximumChanged((double) e.OldValue, (double) e.NewValue);
}
/// <summary>
/// This method is invoked when the Maximum property changes.
/// </summary>
/// <param name="oldMaximum">The old value of the Maximum property.</param>
/// <param name="newMaximum">The new value of the Maximum property.</param>
protected virtual void OnMaximumChanged(double oldMaximum, double newMaximum)
{
}
/// <summary>
/// The DependencyProperty for the Value property.
/// Flags: None
/// Default Value: 0
/// </summary>
public static readonly DependencyProperty ValueProperty =
DependencyProperty.Register(
"Value",
typeof(double),
typeof(RangeBase),
new FrameworkPropertyMetadata(
0.0d,
FrameworkPropertyMetadataOptions.BindsTwoWayByDefault | FrameworkPropertyMetadataOptions.Journal,
new PropertyChangedCallback(OnValueChanged),
new CoerceValueCallback(ConstrainToRange)),
new ValidateValueCallback(IsValidDoubleValue));
// made this internal because Slider wants to leverage it
internal static object ConstrainToRange(DependencyObject d, object value)
{
RangeBase ctrl = (RangeBase) d;
double min = ctrl.Minimum;
double v = (double) value;
if (v < min)
{
return min;
}
double max = ctrl.Maximum;
if (v > max)
{
return max;
}
return value;
}
/// <summary>
/// Value property
/// </summary>
[Bindable(true), Category("Behavior")]
public double Value
{
get { return (double) GetValue(ValueProperty); }
set { SetValue(ValueProperty, value); }
}
/// <summary>
/// Called when ValueID is changed on "d."
/// </summary>
private static void OnValueChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
RangeBase ctrl = (RangeBase)d;
RangeBaseAutomationPeer peer = UIElementAutomationPeer.FromElement(ctrl) as RangeBaseAutomationPeer;
if (peer != null)
{
peer.RaiseValuePropertyChangedEvent((double)e.OldValue, (double)e.NewValue);
}
ctrl.OnValueChanged((double) e.OldValue, (double) e.NewValue);
}
/// <summary>
/// This method is invoked when the Value property changes.
/// </summary>
/// <param name="oldValue">The old value of the Value property.</param>
/// <param name="newValue">The new value of the Value property.</param>
protected virtual void OnValueChanged(double oldValue, double newValue)
{
RoutedPropertyChangedEventArgs<double> args = new RoutedPropertyChangedEventArgs<double>(oldValue, newValue);
args.RoutedEvent=RangeBase.ValueChangedEvent;
RaiseEvent(args);
}
/// <summary>
/// Validate input value in RangeBase (Minimum, Maximum, and Value).
/// </summary>
/// <param name="value"></param>
/// <returns>Returns False if value is NaN or NegativeInfinity or PositiveInfinity. Otherwise, returns True.</returns>
private static bool IsValidDoubleValue(object value)
{
double d = (double)value;
return !(double.IsNaN(d) || double.IsInfinity(d));
}
/// <summary>
/// Validate input value in RangeBase (SmallChange and LargeChange).
/// </summary>
/// <param name="value"></param>
/// <returns>Returns False if value is NaN or NegativeInfinity or PositiveInfinity or negative. Otherwise, returns True.</returns>
private static bool IsValidChange(object value)
{
double d = (double)value;
return IsValidDoubleValue(value) && d >= 0.0;
}
#region LargeChange Property
/// <summary>
/// The DependencyProperty for the LargeChange property.
/// </summary>
public static readonly DependencyProperty LargeChangeProperty
= DependencyProperty.Register("LargeChange", typeof(double), typeof(RangeBase),
new FrameworkPropertyMetadata(1.0),
new ValidateValueCallback(IsValidChange));
/// <summary>
/// LargeChange property
/// </summary>
[Bindable(true), Category("Behavior")]
public double LargeChange
{
get
{
return (double)GetValue(LargeChangeProperty);
}
set
{
SetValue(LargeChangeProperty, value);
}
}
#endregion
#region SmallChange Property
/// <summary>
/// The DependencyProperty for the SmallChange property.
/// </summary>
public static readonly DependencyProperty SmallChangeProperty
= DependencyProperty.Register("SmallChange", typeof(double), typeof(RangeBase),
new FrameworkPropertyMetadata(0.1),
new ValidateValueCallback(IsValidChange));
/// <summary>
/// SmallChange property
/// </summary>
[Bindable(true), Category("Behavior")]
public double SmallChange
{
get
{
return (double)GetValue(SmallChangeProperty);
}
set
{
SetValue(SmallChangeProperty, value);
}
}
#endregion
#endregion
#region Method Overrides
internal override void ChangeVisualState(bool useTransitions)
{
if (!IsEnabled)
{
VisualStates.GoToState(this, useTransitions, VisualStates.StateDisabled, VisualStates.StateNormal);
}
else if (IsMouseOver)
{
VisualStates.GoToState(this, useTransitions, VisualStates.StateMouseOver, VisualStates.StateNormal);
}
else
{
VisualStateManager.GoToState(this, VisualStates.StateNormal, useTransitions);
}
if (IsKeyboardFocused)
{
VisualStates.GoToState(this, useTransitions, VisualStates.StateFocused, VisualStates.StateUnfocused);
}
else
{
VisualStateManager.GoToState(this, VisualStates.StateUnfocused, useTransitions);
}
base.ChangeVisualState(useTransitions);
}
/// <summary>
/// Gives a string representation of this object.
/// </summary>
public override string ToString()
{
string typeText = this.GetType().ToString();
double min = double.NaN;
double max = double.NaN;
double val = double.NaN;
bool valuesDefined = false;
// Accessing RangeBase properties may be thread sensitive
if (CheckAccess())
{
min = Minimum;
max = Maximum;
val = Value;
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)
{
min = Minimum;
max = Maximum;
val = Value;
valuesDefined = true;
return null;
}), null);
}
// If min, max, value are defined
if (valuesDefined)
{
return SR.Format(SR.ToStringFormatString_RangeBase, typeText, min, max, val);
}
// Not able to access the dispatcher
return typeText;
}
#endregion
}
}
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