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InertiaExpansionBehavior Class

Controls the deceleration of a resizing manipulation during inertia.


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

Public Class InertiaExpansionBehavior
<InertiaExpansionBehavior .../>

The InertiaExpansionBehavior type exposes the following members.

Public methodInertiaExpansionBehaviorInitializes a new instance of the InertiaExpansionBehavior class.

Public propertyDesiredDecelerationGets or sets the rate that resizing slows in device-independent units (1/96th inch per unit) per square milliseconds.
Public propertyDesiredExpansionGets or sets the amount the element resizes at the end of inertia.
Public propertyInitialRadiusGets or sets the initial average radius.
Public propertyInitialVelocityGets or sets the initial rate the element resizes at the start of inertia.

Public methodEquals(Object)Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeServes as a hash function for a particular type. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)

The InertiaExpansionBehavior class specifies how a expansion manipulation behaves when it is inertia. Use the ExpansionBehavior property in the ManipulationInertiaStarting event to do the following:

  • Specify the initial velocity of the inertia when it begins by setting the InitialVelocity property.

  • Specify the desired expansion of the manipulation when inertia ends by setting the DesiredExpansion property.

  • Specify the desired deceleration of the inertia by setting the DesiredDeceleration property.

Set either the DesiredExpansion or the DesiredDeceleration, but not both. When you set one of these properties, the other property is changed to Double.NaN if it has a value.

For more information about manipulations, see the Input Overview. For an example of an application that responds to manipulations, see Walkthrough: Creating Your First Touch Application.

The following example shows the ManipulationInertiaStarting event handler and sets the desired deceleration for translation, expansion, and rotation that is used during inertia. This example is part of a larger example in Walkthrough: Creating Your First Touch Application.

Private Sub Window_InertiaStarting(ByVal sender As Object,
                                   ByVal e As ManipulationInertiaStartingEventArgs)

    ' Decrease the velocity of the Rectangle's movement by 
    ' 10 inches per second every second.
    ' (10 inches * 96 pixels per inch / 1000ms^2)
    e.TranslationBehavior.DesiredDeceleration = 10.0 * 96.0 / (1000.0 * 1000.0)

    ' Decrease the velocity of the Rectangle's resizing by 
    ' 0.1 inches per second every second.
    ' (0.1 inches * 96 pixels per inch / (1000ms^2)
    e.ExpansionBehavior.DesiredDeceleration = 0.1 * 96 / (1000.0 * 1000.0)

    ' Decrease the velocity of the Rectangle's rotation rate by 
    ' 2 rotations per second every second.
    ' (2 * 360 degrees / (1000ms^2)
    e.RotationBehavior.DesiredDeceleration = 720 / (1000.0 * 1000.0)

    e.Handled = True
End Sub

.NET Framework

Supported in: 4

.NET Framework Client Profile

Supported in: 4

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), 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.

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