How to wait for animation canvas iframe to be fully loaded?

Hello.

I was wondering what would be the best way to await the load of iframe?

I want to dynamically attach some event listeners to drawn canvas elements but the thing is that canvas is not drawn immediately..

I have added setTimeout function to wait for a second. But this is not great too because if user will be on slow network it won't work as expected.

Maybe someone have idea what could be done in my case?