Making an Ember Computed Property depend on a Variable - ember.js

Question

Suppose I have a computed property on a view:
TestView=Ember.View.extend({
computedProperty:function(){
return this.get("elementId")+"test"
}.property("targetObject.{{elementId goes here}}")
})
I want to make the property depend on the model property with the attribute name equivalent to the id on that view element. However, I haven't found an elegant way to do this. I need to do this to make my code as general as possible. My solution so far is to make the property dependent on targetObject's id and then call object.notifyPropertyChange(id) whenever I need binding to update.
To add some clarity. Suppose I have a view that displays a number that is bound to a property on the model. However, I want the number to be formatted with commas when it is displayed. I could easily write a computed property for each possible attribute that will do the formatting. Instead though, I just want a generic view that will know to take the value of the attribute of the model with the same name as the view's elementId property. Here is an example of my hacky solution:
TestView=Ember.View.extend({
computedProperty:function(){
var id=this.get("elementId")
return addCommas(this.get("targetObject").get(id))
}.property("id")
})
I then call:
object.notifyPropertyChange(id) whenever one of the attributes on the model changes. It works and achieves my goals but I was looking for a more elegant solution.
In the view the formatted value is displayed in an custom textfield.
{{view App.CustomTextField value=computedProperty id="someAttribute}}

Answer 1

Just use a helper which formats numbers with commas. You don't need any properties, computed or otherwise.
test.hbs
Hello, I am a formatted {{add-commas number}}.
helpers/add-commas.js
Ember.Handlebars.helper('add-commas', function(value) {
return value.toLocaleString();
});