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EventSetter Class

  • Reference

Definition

Namespace:
System.Windows
Assembly:
PresentationFramework.dll

Represents an event setter in a style. Event setters invoke the specified event handlers in response to events.

public ref class EventSetter : System::Windows::SetterBase
public class EventSetter : System.Windows.SetterBase
type EventSetter = class
    inherit SetterBase
Public Class EventSetter
Inherits SetterBase
Inheritance
Object
SetterBase
EventSetter

Examples

The following example establishes a single EventSetter within a page-level style.

<StackPanel
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  x:Class="SDKSample.EventOvw2"
  Name="dpanel2"
  Initialized="PrimeHandledToo"
>
  <StackPanel.Resources>
    <Style TargetType="{x:Type Button}">
      <EventSetter Event="Click" Handler="b1SetColor"/>
    </Style>
  </StackPanel.Resources>
  <Button>Click me</Button>
  <Button Name="ThisButton" Click="HandleThis">
    Raise event, handle it, use handled=true handler to get it anyway.
  </Button>
</StackPanel>

The following shows the example event handlers:

void b1SetColor(object sender, RoutedEventArgs e)
{
  Button b = e.Source as Button;
  b.Background = new SolidColorBrush(Colors.Azure);
}

void HandleThis(object sender, RoutedEventArgs e)
{
  e.Handled=true;
}

Private Sub b1SetColor(ByVal sender As Object, ByVal e As RoutedEventArgs)
  Dim b As Button = TryCast(e.Source, Button)
  b.Background = New SolidColorBrush(Colors.Azure)
End Sub

Private Sub HandleThis(ByVal sender As Object, ByVal e As RoutedEventArgs)
  e.Handled=True
End Sub

Remarks

Event setters invoke the specified event handlers in response to routed events, which apply to all elements that reference the Style rather than requiring you to attach instance handlers to each individual element. Only Style.Setters support EventSetter objects.

You can only declare event setters for events that are routed events. You can declare event setters for routed events with a direct routing strategy, bubbling events, or tunneling events.

Instances of the EventSetter class are usually created through Extensible Application Markup Language (XAML), as an object element within a style defined through XAML. An EventSetter might also be instantiated from code.

Event setters cannot be used in a style that is contained in a theme resource dictionary. This is because a theme resource dictionary at run time is often loose binary XAML (BAML) files, and does not have any scope defined where accompanying code-behind that defines the handlers can exist.

Handlers attached through event setters are invoked after any class handlers for an event, and also after any instance handlers. As a result, if a class handler or instance handler marks an event handled in its arguments, then the handler declared by an event setter is not invoked, unless the event setter specifically sets HandledEventsToo true.

Event setters may also come from BasedOn styles. The event setter handlers from the style specified as BasedOn will be invoked after the handlers on the immediate style.

Note that only Style.Setters supports EventSetter objects. Triggers (TriggerBase and derived classes) do not support EventSetter.

Constructors

EventSetter()

Initializes a new instance of the EventSetter class.
EventSetter(RoutedEvent, Delegate)

Initializes a new instance of the EventSetter class, using the provided event and handler parameters.

Properties

Event

Gets or sets the particular routed event that this EventSetter responds to.
HandledEventsToo

Gets or sets a value that determines whether the handler assigned to the setter should still be invoked, even if the event is marked handled in its event data.
Handler

Gets or sets the reference to a handler for a routed event in the setter.
IsSealed

Gets a value that indicates whether this object is in an immutable state.

(Inherited from SetterBase)

Methods

CheckSealed()

Checks whether this object is read-only and cannot be changed.

(Inherited from SetterBase)
Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also