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# startAnimation()

Starts the animation from its current position.

```
func startAnimation()
```

## Discussion

Call this method to start the animations or to resume the animation after they were paused. This method sets the state of the animator to [`UIViewAnimatingState.active`](/documentation/UIKit/UIViewAnimatingState/active), if it isn’t already there. It’s a programmer error to call this method while the state of the animator is set to [`UIViewAnimatingState.stopped`](/documentation/UIKit/UIViewAnimatingState/stopped).

When implementing a custom animator, use this method to transition your animator to the active state and to run the animations. Run your animations from the progress point in the [`fractionComplete`](/documentation/UIKit/UIViewAnimating/fractionComplete) property. Update the [`state`](/documentation/UIKit/UIViewAnimating/state) and [`isRunning`](/documentation/UIKit/UIViewAnimating/isRunning) properties, as well as any other relevant properties of your custom animator object.

---

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