Question

Using KineticJS I figured out how to pass a function as the Gameboard function but all the this’s inside the Gameboard function think’s its now the object that got the function :(.

function Gameboard(){
//.... creates placeholders for stage layers and all objects
this.dice_layer=new Kinetic.Layer();

this.rolldice=function(){
     alert(this.toString());
     //..alter images
     this.dice_layer.draw();//<~~ thinks this is circle once passed through setUpGameBoard says dice_layer is undefined.  alert(this.toString()); shows this to be circle.
};


this.setUpGameBoard=function(){
   // ...draws board pawns creates a circle object
   var obj=this;//<~~ are there memory issues with this?  Is there a better way?
    circle.on("click",**obj**.rolldice.**bind**(obj);//** == ANSWER!!!!


 };  

};

Answer 1

The problem is this line:

    this.doSomething=function(fnction){

You are declaring doSomething as a function with a single parameter, fnction but when you call it, you are passing two – a string and a function.

    this.doSomething=function(str, fnction){

will behave as you expect it.

jsFiddle demo

---

Based on your “solution” to the second problem, it looks like you want to use ES5’s bind. It allows to you specify the this for a particular function call since JavaScript really doesn’t have “methods”, you have to specify the object they operate on.

 this.barfoo.doSomething(this.doBar.bind(this));

An example of malfunctioning code can be compared to the fix with bind.