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PointerEventHandler Delegato

Definizione

Rappresenta il metodo che gestirà gli eventi del messaggio del puntatore, ad esempio PointerPressed.

public delegate void PointerEventHandler(Platform::Object ^ sender, PointerRoutedEventArgs ^ e);
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public delegate void PointerEventHandler(object sender, PointerRoutedEventArgs e);
Public Delegate Sub PointerEventHandler(sender As Object, e As PointerRoutedEventArgs)

Parametri

sender
Object

Platform::Object

Oggetto a cui è associato il gestore eventi.

e
PointerRoutedEventArgs

Dati dell'evento per l'evento.

Attributi

Esempio

Nell'esempio di codice seguente viene illustrato lo scenario 2 dall'esempio di input. Questo codice mostra alcuni modelli di utilizzo per la manipolazione diretta usando gli eventi PointerPressed, PointerReleased, PointerEntered, PointerExited e PointerMoved .

<StackPanel x:Name="Scenario2Output" ManipulationMode="All">
  <StackPanel Orientation="Horizontal" Margin="0,10,0,0">
    <Button x:Name="scenario2Reset" Content="Reset" 
      Margin="0,0,10,0" Click="Scenario2Reset"/>
  </StackPanel>
  <StackPanel Orientation="Horizontal" >
    <ToggleSwitch x:Name="tbPointerCapture" 
      Header="Pointer Capture" FontSize="20"/>
    <TextBlock x:Name="txtCaptureStatus" 
      Style="{StaticResource BasicTextStyle}"/>
  </StackPanel>
  <Border x:Name="bEnteredExited" Background="Red" 
    Height="300" Width="450" CornerRadius="20" 
    HorizontalAlignment="Left">
    <Grid>
      <TextBlock Style="{StaticResource BasicTextStyle}" Text="" 
        HorizontalAlignment="Center" VerticalAlignment="Center" 
        x:Name="bEnteredExitedTextBlock"/>
      <Ellipse VerticalAlignment="Bottom" Stroke="Silver" 
        StrokeDashArray="2,2" StrokeThickness="2" Margin="2" 
        x:Name="bEnteredExitedTimer" Width="20" Height="20" 
        RenderTransformOrigin="0.5,0.5">
        <Ellipse.RenderTransform >
          <RotateTransform Angle="0" />
        </Ellipse.RenderTransform>
      </Ellipse>
    </Grid>
  </Border>
</StackPanel>
int _pointerCount;

public Scenario2()
{
    this.InitializeComponent();
    bEnteredExited.PointerEntered += bEnteredExited_PointerEntered;
    bEnteredExited.PointerExited += bEnteredExited_PointerExited;
    bEnteredExited.PointerPressed += bEnteredExited_PointerPressed;
    bEnteredExited.PointerReleased += bEnteredExited_PointerReleased;
    bEnteredExited.PointerMoved += bEnteredExited_PointerMoved;

    // To code for multiple Pointers (that is, fingers), 
    // we track how many entered/exited.
    _pointerCount = 0;
}

private void bEnteredExited_PointerMoved(object sender, 
    PointerRoutedEventArgs e)
{
    Scenario2UpdateVisuals(sender as Border, "Moved");
}

private void bEnteredExited_PointerReleased(object sender, 
    PointerRoutedEventArgs e)
{
    ((Border)sender).ReleasePointerCapture(e.Pointer);
    txtCaptureStatus.Text = string.Empty;
}

//Can only get capture on PointerPressed (i.e. touch down, mouse click, pen press)
private void bEnteredExited_PointerPressed(object sender, 
    PointerRoutedEventArgs e)
{
    if (tbPointerCapture.IsOn)
    {
        bool _hasCapture = ((Border)sender).CapturePointer(e.Pointer);
        txtCaptureStatus.Text = "Got Capture: " + _hasCapture;
    }
}

private void bEnteredExited_PointerExited(object sender, 
    PointerRoutedEventArgs e)
{
    _pointerCount--;
    Scenario2UpdateVisuals(sender as Border, "Exited");
}

private void bEnteredExited_PointerEntered(object sender, 
    PointerRoutedEventArgs e)
{
    _pointerCount++;
    Scenario2UpdateVisuals(sender as Border, "Entered");
}

private void Scenario2UpdateVisuals(Border border, 
    String eventDescription)
{
    switch (eventDescription.ToLower())
    {
        case "exited":
            if (_pointerCount <= 0)
            {
                border.Background = new SolidColorBrush(Colors.Red);
                bEnteredExitedTextBlock.Text = eventDescription;
            }
            break;
        case "moved":
            RotateTransform rt = 
                (RotateTransform)bEnteredExitedTimer.RenderTransform;
            rt.Angle += 2;
            if (rt.Angle > 360) rt.Angle -= 360;
            break;
        default:
            border.Background = new SolidColorBrush(Colors.Green);
            bEnteredExitedTextBlock.Text = eventDescription;
            break;
    }
}

private void Scenario2Reset(object sender, RoutedEventArgs e)
{
    Scenario2Reset();
}

private void Scenario2Reset()
{
    bEnteredExited.Background = new SolidColorBrush(Colors.Green);
    bEnteredExitedTextBlock.Text = string.Empty;
}

Commenti

Questo delegato viene usato per gestire ognuno degli eventi seguenti:

Si applica a