PointerEventHandler Delegate

Reference

Definition

Namespace:: Microsoft.UI.Xaml.Input

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Edit

Represents the method that will handle pointer message events such as 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)

Parameters

sender: Object
Platform::Object

The object where the event handler is attached.

e: PointerRoutedEventArgs

Event data for the event.

Attributes: ContractVersionAttribute GuidAttribute

Examples

The following code example shows scenario 2 from the Input sample. This code shows some usage patterns for direct manipulation using the PointerPressed, PointerReleased, PointerEntered, PointerExited, and PointerMoved events.

<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;
}

Remarks

This delegate is used for handling each of the following events:

Applies to