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ManipulationDeltaEventArgs Class

Provides data for the ManipulationDelta event.

Namespace:  System.Windows.Input
Assembly:  PresentationCore (in PresentationCore.dll)

public sealed class ManipulationDeltaEventArgs : InputEventArgs

The ManipulationDeltaEventArgs class contains data about changes in the position of a manipulation. The DeltaManipulation property contains the changes that occurred since the last ManipulationDelta event occurred. The CumulativeManipulation property contains the total changes that occurred for the current manipulation. You use one of those properties to transform the manipulated object.

You can end a manipulation by calling the Complete method or force the manipulation into inertia by calling the StartInertia method.

The following example shows an event handler for the ManipulationDelta event. The example uses the DeltaManipulation property to move, resize, and rotate a Rectangle. The example also checks whether the ManipulationDelta event occurred during inertia and whether the rectangle is touching the edge of a window. If those cases are true, the application stops the manipulation to prevent the rectangle from leaving the visible area of the application. This example is part of a larger example in Walkthrough: Creating Your First Touch Application.


void Window_ManipulationDelta(object sender, ManipulationDeltaEventArgs e)
{

    // Get the Rectangle and its RenderTransform matrix.
    Rectangle rectToMove = e.OriginalSource as Rectangle;
    Matrix rectsMatrix = ((MatrixTransform)rectToMove.RenderTransform).Matrix;

    // Rotate the Rectangle.
    rectsMatrix.RotateAt(e.DeltaManipulation.Rotation, 
                         e.ManipulationOrigin.X, 
                         e.ManipulationOrigin.Y);

    // Resize the Rectangle.  Keep it square 
    // so use only the X value of Scale.
    rectsMatrix.ScaleAt(e.DeltaManipulation.Scale.X, 
                        e.DeltaManipulation.Scale.X, 
                        e.ManipulationOrigin.X,
                        e.ManipulationOrigin.Y);

    // Move the Rectangle.
    rectsMatrix.Translate(e.DeltaManipulation.Translation.X,
                          e.DeltaManipulation.Translation.Y);

    // Apply the changes to the Rectangle.
    rectToMove.RenderTransform = new MatrixTransform(rectsMatrix);

    Rect containingRect =
        new Rect(((FrameworkElement)e.ManipulationContainer).RenderSize);

    Rect shapeBounds =
        rectToMove.RenderTransform.TransformBounds(
            new Rect(rectToMove.RenderSize));

    // Check if the rectangle is completely in the window.
    // If it is not and intertia is occuring, stop the manipulation.
    if (e.IsInertial && !containingRect.Contains(shapeBounds))
    {
        e.Complete();
    }


    e.Handled = true;
}


System.Object
  System.EventArgs
    System.Windows.RoutedEventArgs
      System.Windows.Input.InputEventArgs
        System.Windows.Input.ManipulationDeltaEventArgs

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role not supported), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 4

.NET Framework Client Profile

Supported in: 4

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