setInterval, this, again

Question

I have a problem in regard to setInterval that I can\'t figure out.

There is the problem with the scope when calling setInterval or timeout fro

Answer 1

This is your problem simplified to bare bones:

var ship = {
    name: 'Sheep',
    ding: function() {
        console.log(this.name);
    }
}

setTimeout(ship.ding, 1000); // doesn't work correctly

It may help to see another example to understand why the above doesn't work:

var ding = ship.ding;
ding(); // doesn't work either

In JavaScript this depends on how you call your function. ship.ding() will set this to the sheep object. Bare ding() call will set this to the window object.

You can bind the function to the object you want by using .bind() method. (Function.prototype.bind())

var ding = ship.ding.bind(ship);
ding(); // works

ding is now permanently bound to the sheep object. You can use exactly the same approach with setTimeout:

setTimeout(ship.ding.bind(ship), 1000);