---
title: "storeOverlayWillStartPresentation(_:transitionContext:)"
framework: storekit
role: symbol
role_heading: Instance Method
path: "storekit/skoverlaydelegate/storeoverlaywillstartpresentation(_:transitioncontext:)"
---

# storeOverlayWillStartPresentation(_:transitionContext:)

Indicates that the platform presents an overlay.

## Declaration

```swift
optional func storeOverlayWillStartPresentation(_ overlay: SKOverlay, transitionContext: SKOverlay.TransitionContext)
```

## Parameters

- `overlay`: An overlay object that’s about to appear.
- `transitionContext`: A context you can use to animate changes to UI components as the overlay appears.

## Discussion

Discussion Use the transitionContext parameter to animate updates to the UI on the main thread. For example, make a UIImageView disappear by animating the change of its opacity to 0% as shown in the following code: func storeOverlayWillStartPresentation(_ overlay: SKOverlay, transitionContext: SKOverlay.TransitionContext) {     transitionContext.addAnimation { [self] in         self.imageView.layer.opacity = 0     } }

## See Also

### Responding to the Overlay’s Appearance and Disappearance

- [storeOverlayDidFinishPresentation(_:transitionContext:)](storekit/skoverlaydelegate/storeoverlaydidfinishpresentation(_:transitioncontext:).md)
- [storeOverlayWillStartDismissal(_:transitionContext:)](storekit/skoverlaydelegate/storeoverlaywillstartdismissal(_:transitioncontext:).md)
- [storeOverlayDidFinishDismissal(_:transitionContext:)](storekit/skoverlaydelegate/storeoverlaydidfinishdismissal(_:transitioncontext:).md)
- [SKOverlay.TransitionContext](storekit/skoverlay/transitioncontext.md)