Force Draw() on an Area

I'm trying to figure out how to call `Draw()` on a `ui.Area` because I'd like to animate a region based on a go Timer. Is this possible? I don't see anything in the docs about this, and the only reference I see in the code that's related to the `uiTimer` functionality of libui is a single line at the end of main.go:
```
// TODO Timer?
```

But perhaps there's an idiom I'm missing. So, is there any way to either explicitly drive the `Draw()` method from my code or attach a callback to a timer?