Question

I’m new to knockout js and got an observable array, when populating the array I subscribe on a property of each instance I’m adding, when the property changed (due to user interaction) I need to know which object changed, but knockout give me only the new value of the relevant property.
Is it possible to get the object? (I tried “this” in the function context without success)

  length.isSelected.subscribe(function (isSelected) {
                if (isSelected) { // no access to actual object only the isSelected value
                    debugger;
                    spotLenghts.push(this);
                } else {
                    spotLenghts.pop(this);
                }
            });

Answer 1

The subscribe function takes a second argument that is the target. It will control what this will be set to when your function is executed.

So, you can potentially pass length (or a higher level object that you are creating as appropriate) as the second argument and be able to use this in your handler.