Javascript Novice flailing helplessly

I've been running into issues lately when trying to build custom cell templates that attempting to pass functions as parameters. I suspect this betrays my fundamental lack of understanding of javascript scopes and the this keyword. I have not had any luck on the net, as the stuff in this project is far more advanced than any JS tutorial i've seen on the net. I suppose I could risk my limited cash on a book, but in this day and age???

What I am trying to do here in the attached code is to create a template that contains a checkbox input, a hidden input, and a displayed label. and have the label default to the grid cells item text property from the corresponding model element.
fn(){return this.getItemProperty("text")}

I run into this problem all the time, I presumee b/c I just don't understand what is going on. My code fails from the line

label.setContent("text", function() { return this.getItemProperty("text"); });

If anyone can enlighten me (JS links, advice, recommended carreer changes;) I would really appreciate it. This same scenario seems to work sometimes, and not others, and I don't see the difference.

Thanks,
Here is the full code

Active.Templates.Checkbox = Active.System.Template.subclass();

Active.Templates.Checkbox.create = function(){

/****************************************************************
    Checkbox Cell template.
*****************************************************************/
    var obj = this.prototype;
    var _super = this.superclass.prototype;

    obj.setTag("div");
    obj.setClass("templates","input");

    obj.defineTemplate("checkbox", new Active.HTML.INPUT);
    obj.defineTemplate("hidden", new Active.HTML.INPUT);
    obj.defineTemplate("label", new Active.HTML.SPAN);


    var checkbox = obj.getCheckboxTemplate();
    checkbox.setClass("input","checkbox");
    checkbox.setClass("checkbox",function(){return this.getColumnProperty("index");});
    checkbox.setAttribute("type","checkbox");

    var hidden = obj.getHiddenTemplate();
    hidden.setAttribute("type","hidden");

    var label = obj.getLabelTemplate();
    label.setClass("checkbox","label");
    label.setContent("text", function() { return this.getItemProperty("text"); });
    obj.setLabel = function( l ) {
        var lbl = this.getLabelTemplate();
        lbl.setContent( "text", l );
    }

    obj.setContent("checkbox", checkbox );
    obj.setContent("hidden", function() { return this.getHiddenTemplate(); } );
    obj.setContent("label", function() { return this.getLabelTemplate() });

};

Active.Templates.Checkbox.create();

I would rather use the static content here instead of templates:

var My = new Object;

My.Templates = new Object;

My.Templates.Checkbox = Active.System.Template.subclass();

My.Templates.Checkbox.create = function(){

    var obj = this.prototype;

    obj.setClass("templates","input");

    var checkbox = new Active.HTML.INPUT;
    checkbox.setClass("input","checkbox");
    checkbox.setClass("checkbox",function(){return this.getColumnProperty("index");});
    checkbox.setAttribute("type","checkbox");

    var hidden = new Active.HTML.INPUT;
    hidden.setAttribute("type","hidden");

    var label = new Active.HTML.SPAN;
    label.setClass("checkbox","label");
    label.setContent("text", function() { return this.getItemProperty("text"); });

    obj.setContent("checkbox", checkbox );
    obj.setContent("hidden", hidden);
    obj.setContent("label", label);

};

My.Templates.Checkbox.create();

var obj = new Active.Controls.Grid;
...
obj.setColumnTemplate(new My.Templates.Checkbox, 1);
...

The issue 'static content' vs 'dynamic templates' probably requires more explanations - I will try to write more on this in a few days.

There is one important difference in behavior which you already noticed - keyword 'this' always refers to template (or control) even when used in a function attached to inner static content of this template (control). This is not feature of JS - this is how I decided to run those functions (i.e. as method of template).

I use call() method of the Function object to execute the function as a method of an arbitrary object:

myFunction.call(myObject, arg1, arg2 ...);

In this case keyword 'this' inside the myFunction will refer to myObject regardless where myFunction was originally defined or stored.

Recommended reading ;-)

http://w3future.com/html/stories/hop.xml
http://w3future.com/html/stories/callbacks.xml
http://www.crockford.com/#javascript
http://www.crockford.com/javascript/jslint.html (read source code!)
http://www.jibbering.com/faq/faq_notes/closures.html

Thank you very much. Your way not only works but seems a much cleaner implementation. I look forward to a static versus dynamic post, and will occupy myself with the referenced articles until then.

Thanks again for the very well written and easily extensible library.