Article
11/18/2011

TouchPoint Class

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Represents a single touch point from a touch message source.

Inheritance Hierarchy

System.Object
System.Windows.DependencyObject
System.Windows.Input.TouchPoint

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

Syntax

'Declaration
Public NotInheritable Class TouchPoint _
    Inherits DependencyObject

public sealed class TouchPoint : DependencyObject

The TouchPoint type exposes the following members.

Constructors

	Name	Description
	TouchPoint	Initializes a new instance of the TouchPoint class.

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Properties

	Name	Description
	Action	Gets the type of action (up, down, move) that the TouchPoint represents.
	Dispatcher	Gets the Dispatcher this object is associated with. (Inherited from DependencyObject.)
	Position	Gets the X,Y coordinate position of the touch point as a Point.
	Size	Gets the rectangular area that is reported as the touch-point contact area.
	TouchDevice	Gets the specific device type that produced the touch point.

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Methods

	Name	Description
	CheckAccess	Determines whether the calling thread has access to this object. (Inherited from DependencyObject.)
	ClearValue	Clears the local value of a dependency property. (Inherited from DependencyObject.)
	Equals(Object)	Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
	Finalize	Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
	GetAnimationBaseValue	Returns any base value established for a Silverlight dependency property, which would apply in cases where an animation is not active. (Inherited from DependencyObject.)
	GetHashCode	Serves as a hash function for a particular type. (Inherited from Object.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	GetValue	Returns the current effective value of a dependency property from a DependencyObject. (Inherited from DependencyObject.)
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	ReadLocalValue	Returns the local value of a dependency property, if a local value is set. (Inherited from DependencyObject.)
	SetValue	Sets the local value of a dependency property on a DependencyObject. (Inherited from DependencyObject.)
	ToString	Returns a string that represents the current object. (Inherited from Object.)

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Fields

	Name	Description
	ActionProperty	Identifies the Action dependency property.
	PositionProperty	Identifies the Position dependency property.
	SizeProperty	Identifies the Size dependency property.
	TouchDeviceProperty	Identifies the TouchDevice dependency property.

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Remarks

You get a TouchPoint value from one of two techniques, both of which require handling the FrameReported event and then working with the TouchFrameEventArgs event data:

Call GetPrimaryTouchPoint to get the primary touch point. If you are not processing your own gestures, the primary touch point is often the only data point you need.
Call GetTouchPoints. Using the returned collection, work with the TouchPoint items that are relevant to how your application processes touch input.

The Position of a TouchPoint is always the center of its contact area. To get a bounding box for a specified TouchPoint, you can center a bounding box on the Position point, with the dimensions of that bounding box based on Size.

Touch input requires hardware that is touch-sensitive and an environment that supports the infrastructure to expose touch events to individual applications. For more information, see Touch Input in Silverlight.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Thread Safety

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

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