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# stageTransition

The transition value for the stage of a pressure gesture event.

```
var stageTransition: CGFloat { get }
```

## Discussion

This property is specifically intended to provide a value for the transition animation between the stages of a pressure gesture event.

Gesture events of type [`NSEvent.EventType.pressure`](/documentation/AppKit/NSEvent/EventType/pressure) go through stages, and transitions occur between these stages. This property indicates a transition value between the current stage and the next or prior stage.

This value is distinct from pressure. It immediately resets to `0` as soon as a stage transition occurs. However, this value does not then immediately begin to fluctuate. The value only starts to change as a new stage begins to approach. It then continues to rise or fall throughout the transition, until that new stage is reached.

As pressure increases for the gesture and a new stage approaches, this property provides a value between `0` and `1`, indicating the approach of the next stage. When pressure is reduced for the gesture and a new stage is approached, this property provides a value between `0` and `-1`, indicating the approach of the current stage’s release.

## See Also

[`NSEvent.EventType`](/documentation/AppKit/NSEvent/EventType)

Constants for the types of events that responder objects can handle.

[`NSEvent.EventType.pressure`](/documentation/AppKit/NSEvent/EventType/pressure)

An event that reports a change in pressure on a pressure-sensitive device.


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