PointerEventHandler Delegat

Referenz

Definition

Namespace:: Microsoft.UI.Xaml.Input

Wichtig

Einige Informationen beziehen sich auf Vorabversionen, die vor dem Release ggf. grundlegend überarbeitet werden. Microsoft übernimmt hinsichtlich der hier bereitgestellten Informationen keine Gewährleistungen, seien sie ausdrücklich oder konkludent.

Bearbeiten

Stellt die Methode dar, die Zeigernachrichtenereignisse verarbeitet, z. B. PointerPressed.

public delegate void PointerEventHandler(Platform::Object ^ sender, PointerRoutedEventArgs ^ e);

[Windows.Foundation.Metadata.ContractVersion(typeof(Microsoft.UI.Xaml.WinUIContract), 65536)]
[Windows.Foundation.Metadata.Guid(2760536545, 35764, 21911, 158, 49, 144, 58, 63, 106, 4, 251)]
public delegate void PointerEventHandler(object sender, PointerRoutedEventArgs e);

Public Delegate Sub PointerEventHandler(sender As Object, e As PointerRoutedEventArgs)

Parameter

sender: Object
Platform::Object

Das Objekt, an das der Ereignishandler angefügt ist.

e: PointerRoutedEventArgs

Die Ereignisdaten für das Ereignis.

Attribute: ContractVersionAttribute GuidAttribute

Beispiele

Das folgende Codebeispiel zeigt Szenario 2 aus dem Eingabebeispiel. Dieser Code zeigt einige Verwendungsmuster für die direkte Bearbeitung mit den Ereignissen PointerPressed, PointerReleased, PointerEntered, PointerExited und 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;
}

Hinweise

Dieser Delegat wird für die Behandlung der folgenden Ereignisse verwendet:

Gilt für:

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