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# progressHandler

A custom block that runs at the same time as the system animations.

```
var progressHandler: ((Float) -> Void)? { get set }
```

## Discussion

If you have animations you want to run at the same time as the system
animations, assign a block to this property and use it to run your
animations. The block you provide must have no return value and take
a floating-point value as a parameter. The parameter indicates the
current progress of the animations as a percentage value between
`0.0` to `1.0`. The system executes your block multiple times during
the course of the animations, providing an updated completion value each time.

---

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