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UIElement.GotKeyboardFocus (Evento)

Occurs when the keyboard is focused on this element.

Espacio de nombres: System.Windows
Ensamblado: PresentationCore (en presentationcore.dll)
Espacio de nombres XML:  http://schemas.microsoft.com/winfx/2006/xaml/presentation

public event KeyboardFocusChangedEventHandler GotKeyboardFocus
/** @event */
public final void add_GotKeyboardFocus (KeyboardFocusChangedEventHandler value)

/** @event */
public final void remove_GotKeyboardFocus (KeyboardFocusChangedEventHandler value)

En JScript, se pueden controlar los eventos que define una clase, pero no se pueden definir unos propios.
<object GotKeyboardFocus="KeyboardFocusChangedEventHandler" .../>

Identifier field

GotKeyboardFocusEvent

Routing strategy

Bubbling

Delegate

KeyboardFocusChangedEventHandler

IsKeyboardFocusedChanged is a similar event that tracks status changes in a property that maintains the focus state for an element; the GotKeyboardFocus event is raised in many of the same circumstances.

Because this event uses bubbling routing, the element that has focus might be a child element instead of the element where the event handler is actually attached. Check the Source in the event data to determine the actual element that has focus.

This event creates an alias for the Keyboard.GotKeyboardFocus  attached event for this class so that GotKeyboardFocus is part of the class members list when UIElement is inherited as a base element. Event handlers that are attached to the GotKeyboardFocus event are attached to the underlying Keyboard.GotKeyboardFocus attached event and receive the same event data instance.

This example shows how to change the color of an element when it gains and loses focus by using the GotFocus and LostFocus events.

This example consists of a Extensible Application Markup Language (XAML) file and a code-behind file. For the complete samples, see Firing Events when an Element Gains and Loses Focus Sample.

The following XAML creates the user interface, which consists of two Button objects, and attaches event handlers for the GotFocus and LostFocus events to the Button objects.

<StackPanel>
  <StackPanel.Resources>
    <Style TargetType="{x:Type Button}">
      <Setter Property="Height" Value="20"/>
      <Setter Property="Width" Value="250"/>
      <Setter Property="HorizontalAlignment" Value="Left"/>
    </Style>
  </StackPanel.Resources>
  <Button
      GotFocus="OnGotFocusHandler"
      LostFocus="OnLostFocusHandler">Click Or Tab To Give Keyboard Focus</Button>
  <Button
      GotFocus="OnGotFocusHandler"
      LostFocus="OnLostFocusHandler">Click Or Tab To Give Keyborad Focus</Button>
</StackPanel>

The following code behind creates the GotFocus and LostFocus event handlers. When the Button gains keyboard focus, the Background of the Button is changed to red. When the Button loses keyboard focus, the Background of the Button is changed back to white.

public partial class Window1 : Window
{
    public Window1()
    {
        InitializeComponent();
    }

    // Raised when Button gains focus.
    // Changes the color of the Button to Red.
    private void OnGotFocusHandler(object sender, RoutedEventArgs e)
    {
        Button tb = e.Source as Button;
        tb.Background = Brushes.Red;
    }
    // Raised when Button losses focus. 
    // Changes the color of the Button back to white.
    private void OnLostFocusHandler(object sender, RoutedEventArgs e)
    {
        Button tb = e.Source as Button;
        tb.Background = Brushes.White;
    }
}

Microsoft .NET Framework 3.0 es compatible con Windows Vista, Microsoft Windows XP SP2 y Windows Server 2003 SP1.

.NET Framework

Compatible con: 3.0

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