---
title: "collisionBehavior(_:endedContactFor:withBoundaryIdentifier:)"
framework: uikit
role: symbol
role_heading: Instance Method
path: "uikit/uicollisionbehaviordelegate/collisionbehavior(_:endedcontactfor:withboundaryidentifier:)"
---

# collisionBehavior(_:endedContactFor:withBoundaryIdentifier:)

Called when a collision between a dynamic item and a boundary has ended.

## Declaration

```swift
optional func collisionBehavior(_ behavior: UICollisionBehavior, endedContactFor item: any UIDynamicItem, withBoundaryIdentifier identifier: (any NSCopying)?)
```

## Parameters

- `behavior`: The collision behavior that owns the dynamic item that has ended contact.
- `item`: The dynamic item that collided.
- `identifier`: The identifier of the boundary that the dynamic item collided with.

## See Also

### Responding to UIKit Dynamics collisions

- [collisionBehavior(_:beganContactFor:withBoundaryIdentifier:at:)](uikit/uicollisionbehaviordelegate/collisionbehavior(_:begancontactfor:withboundaryidentifier:at:).md)
- [collisionBehavior(_:beganContactFor:with:at:)](uikit/uicollisionbehaviordelegate/collisionbehavior(_:begancontactfor:with:at:).md)
- [collisionBehavior(_:endedContactFor:with:)](uikit/uicollisionbehaviordelegate/collisionbehavior(_:endedcontactfor:with:).md)