InteractionTracker.NaturalRestingScale Property

Definition

Namespace:

Microsoft.UI.Composition.Interactions

Natural resting scale for the InteractionTracker.

The NaturalRestingScale property is the calculated scale position that InteractionTracker will come to a stop at without accounting for boundaries or inertia modifiers. This property is often useful for actions like virtualization in a scrolling experience, where it is important to know the location of where InteractionTracker will stop. There are two main use cases for using the NaturalRestingScale property: Retrieving its current value in the InertiaStateEntered event args or referencing this property in an ExpressionAnimation when creating things like inertia modifiers.

public:
 property float NaturalRestingScale { float get(); };

float NaturalRestingScale();

public float NaturalRestingScale { get; }

var single = interactionTracker.naturalRestingScale;

Public ReadOnly Property NaturalRestingScale As Single

Property Value

Single

float

Natural resting scale for the InteractionTracker.

Examples

// Listen for the InertiaStateEntered event
public void InertiaStateEntered(InteractionTracker sender, 	InteractionTrackerInertiaStateEnteredArgs args)
{
  // Grab the NaturalRestingScale out of the args when the event is fired.
  float scaleRest = args.NaturalRestingScale;
}
void CreateBasicScaleSnapPoint(float maxScale, float minScale)
{
  var snappoint = InteractionTrackerInertiaRestingValue.Create(_compositor);

  // Reference the NaturalRestingScale of InteractionTracker in an ExpressionAnimation for conditional portion of an InertiaModifier.
  snappoint.Condition = _compositor.CreateExpressionAnimation("this.target.NaturalRestingScale >= min && this.target.NaturalRestingScale < max ");

  snappoint.Condition.SetScalarParameter("min", minScale);
  snappoint.Condition.SetScalarParameter("max", maxScale);

  // Snap to the highbound if condition met
  snappoint.RestingValue = _compositor.CreateExpressionAnimation("max");
  snappoint.RestingValue.SetScalarParameter("max", maxScale);

  scaleInertiaModifier.Add(snappoint);

  _tracker.ConfigureScaleInertiaModifiers(scaleInertiaModifier);
}

Remarks

The two use cases described in the code snippet are the primary uses of the NaturalRestingScale property. Although you may be tempted to reference this property off InteractionTracker like any other object.property relationship, you will not always get the most up-to-date value. It is recommended in this situation that you listen for the InertiaStateEntered event and grab the latest value from the arguments.