Tween onUpdate

[charlie_says]

I've just been playing around with some tweens, and was hoping to do something on the update of one of them...

But, 

tween1.onUpdate.add(this.updateItem, this);

generates the error:

Uncaught TypeError: Cannot read property 'add' of undefined

 

I can see from the docs (& source) there is reference to onUpdateCallback, and so I'd expected it to work int he same way as onStart and onComplete.

 

(I have also tried setting onUpdateCallback directly, but this hasn't helped).

 

Any idea where I'm going wrong?

 

[charlie_says]

Must have been having "a moment"

tween1.onUpdateCallback(this.updateItem, this);

works fine.

[MaraRoses]

And if i want to pass some parameter for checking frames and return some signal?
 

this.slideTween.onUpdateCallback(this.updateItem, this)