PointerRoutedEventArgs Class

Definition

Namespace:

Microsoft.UI.Xaml.Input

Contains the arguments returned by the last pointer event message.

public ref class PointerRoutedEventArgs sealed : RoutedEventArgs

/// [Windows.Foundation.Metadata.ContractVersion(Microsoft.UI.Xaml.WinUIContract, 65536)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
/// [Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
class PointerRoutedEventArgs final : RoutedEventArgs

[Windows.Foundation.Metadata.ContractVersion(typeof(Microsoft.UI.Xaml.WinUIContract), 65536)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
[Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
public sealed class PointerRoutedEventArgs : RoutedEventArgs

Public NotInheritable Class PointerRoutedEventArgs
Inherits RoutedEventArgs

Inheritance

Object Platform::Object IInspectable RoutedEventArgs PointerRoutedEventArgs

Attributes

ContractVersionAttribute MarshalingBehaviorAttribute ThreadingAttribute

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

In most cases, we recommend that you get pointer info through the event argument of the pointer event handlers.

If the event argument doesn't intrinsically expose the pointer details required by your app, you can get access to extended pointer data through the GetCurrentPoint and GetIntermediatePoints methods of PointerRoutedEventArgs. Use these methods to specify the context of the pointer data.

The PointerRoutedEventArgs event data class is used for these events:

• PointerPressed
• PointerCanceled
• PointerCaptureLost
• PointerEntered
• PointerExited
• PointerMoved
• PointerReleased
• PointerWheelChanged

Important

Mouse input is associated with a single pointer assigned when mouse input is first detected. Clicking a mouse button (left, wheel, or right) creates a secondary association between the pointer and that button through the PointerPressed event. The PointerReleased event is fired only when that same mouse button is released (no other button can be associated with the pointer until this event is complete). Because of this exclusive association, other mouse button clicks are routed through the PointerMoved event. You can test the mouse button state when handling this event, as shown in the following example.

private void Target_PointerMoved(object sender, PointerRoutedEventArgs e)
{
    Pointer ptr = e.Pointer;

    // Multiple, simultaneous mouse button inputs are processed here.
    // Mouse input is associated with a single pointer assigned when 
    // mouse input is first detected. 
    // Clicking additional mouse buttons (left, wheel, or right) during 
    // the interaction creates secondary associations between those buttons 
    // and the pointer through the pointer pressed event. 
    // The pointer released event is fired only when the last mouse button 
    // associated with the interaction (not necessarily the initial button) 
    // is released. 
    // Because of this exclusive association, other mouse button clicks are 
    // routed through the pointer move event.          
    if (ptr.PointerDeviceType == PointerDeviceType.Mouse)
    {
        // To get mouse state, we need extended pointer details.
        // We get the pointer info through the getCurrentPoint method
        // of the event argument. 
        PointerPoint ptrPt = e.GetCurrentPoint(Target);
        if (ptrPt.Properties.IsLeftButtonPressed)
        {
            eventLog.Text += "\nLeft button: " + ptrPt.PointerId;
        }
        if (ptrPt.Properties.IsMiddleButtonPressed)
        {
            eventLog.Text += "\nWheel button: " + ptrPt.PointerId;
        }
        if (ptrPt.Properties.IsRightButtonPressed)
        {
            eventLog.Text += "\nRight button: " + ptrPt.PointerId;
        }
    }

    // Prevent most handlers along the event route from handling the same event again.
    e.Handled = true;

    // Display pointer details.
    updateInfoPop(e);
}

• The value of sender (which is on the delegate signature, not this event data class).
• Specific members of PointerRoutedEventArgs, such as KeyModifiers or GetCurrentPoint.
• Values of a Pointer device description class. Get the Pointer from the Pointer property.
• Members that come from the system input conceptualization of a PointerPoint. Use the GetCurrentPoint API to get a PointerPoint value, then call PointerPoint API such as PointerPoint.Position and PointerPointProperties.

Specific events often have information available in the various pointer device and pointer point classes that is mainly only relevant for that event. For example, when you handle PointerWheelChanged, you might be interested in the MouseWheelDelta from PointerPointProperties.

The object retrieved by the GetCurrentPoint and GetIntermediatePoints methods provide access to extended pointer info through the Properties property, which gets a PointerPointProperties object.

In the following example, we get extended pointer properties through the PointerPoint and PointerPointProperties objects. (See Handle pointer input for the complete example.)

String queryPointer(PointerPoint ptrPt)
{
    String details = "";

    switch (ptrPt.PointerDeviceType)
    {
        case PointerDeviceType.Mouse:
            details += "\nPointer type: mouse";
            break;
        case PointerDeviceType.Pen:
            details += "\nPointer type: pen";
            if (ptrPt.IsInContact)
            {
                details += "\nPressure: " + ptrPt.Properties.Pressure;
                details += "\nrotation: " + ptrPt.Properties.Orientation;
                details += "\nTilt X: " + ptrPt.Properties.XTilt;
                details += "\nTilt Y: " + ptrPt.Properties.YTilt;
                details += "\nBarrel button pressed: " + ptrPt.Properties.IsBarrelButtonPressed;
            }
            break;
        case PointerDeviceType.Touch:
            details += "\nPointer type: touch";
            details += "\nrotation: " + ptrPt.Properties.Orientation;
            details += "\nTilt X: " + ptrPt.Properties.XTilt;
            details += "\nTilt Y: " + ptrPt.Properties.YTilt;
            break;
        default:
            details += "\nPointer type: n/a";
            break;
    }

    GeneralTransform gt = Target.TransformToVisual(panel);
    Point screenPoint;

    screenPoint = gt.TransformPoint(new Point(ptrPt.Position.X, ptrPt.Position.Y));
    details += "\nPointer Id: " + ptrPt.PointerId.ToString() +
        "\nPointer location (parent): " + ptrPt.Position.X + ", " + ptrPt.Position.Y +
        "\nPointer location (screen): " + screenPoint.X + ", " + screenPoint.Y;
    return details;
}

Typically, the object returned by this method is used to feed pointer data to a GestureRecognizer. Another scenario is getting the MouseWheelDelta for a PointerWheelChanged event; that value is in PointerPointProperties.

Properties

Handled	Gets or sets a value that marks the routed event as handled, and prevents most handlers along the event route from handling the same event again.
IsGenerated	Gets a value that indicates whether the pointer event occurred from direct interaction with an object by the user, or was generated by the platform based on changes to the UI of the application.
KeyModifiers	Gets a value that indicates which key modifiers were active at the time that the pointer event was initiated.
OriginalSource	Gets a reference to the object that raised the event. This is often a template part of a control rather than an element that was declared in your app UI. (Inherited from RoutedEventArgs)
Pointer	Gets a reference to a pointer token.

Methods

GetCurrentPoint(UIElement)	Retrieves a PointerPoint object that provides basic info about the pointer associated with the event.
GetIntermediatePoints(UIElement)	Retrieves a collection of PointerPoint objects that represent the pointer history from the last pointer event up to and including the current pointer event. Each PointerPoint in the collection provides basic info about the pointer associated with the event. The last item in the collection is equivalent to the PointerPoint object returned by GetCurrentPoint.

See also

• RoutedEventArgs
• PointerPressed