Question

I’m trying to call mozRequestAnimationFrame in firefox, but I keep getting an error. Here is my code:

var obj={
    animFrame:mozRequestAnimationFrame
}

var animF=mozRequestAnimationFrame;

function a(){
 console.log('a called');   
}

animF(a);

obj.animFrame(a);

The error occurs with the obj.animFrame(a); I get an error message of:

Illegal operation on WrappedNative prototype object

I found this thread on SO: requestAnimationFrame with this keyword
and then figured that maybe requestanimationframe didn’t have the right “this” context, so I tried

obj.animFrame(a).bind(window);

but still got the same error message. So why is the error occurring?

Answer 1

I dont know reason why you need to save pointer to requestAnimationFrame (mozRequestAnimationFrame) into some object, but try next code to avoid error:

var obj={
    animFrame:mozRequestAnimationFrame.bind(window)
}

function a(){
 console.log('a called');   
}

obj.animFrame(a);