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Helper objects in javascript

I know that you can create literals with subobjects and functions:

var obj = {
    val : 1,
    level1 : {
        val : 2,
        val2 : 3,
        func : function(){
            return this.val2
        }
    }
}

console.log(obj.val);
console.log(obj.level1.val);
console.log(obj.level1.func());

outputs:

1
2
3

What I would like to do is do the same with the methods in the object, something similar to:

function objType() {
    this.val = 1;
    this.func = function(){
        return this.val;
    }
    this.level1 = function(){
        this.val = 2;
        this.func = function(){
            return this.val;
        }
        this.level2 = function(){
            this.val = 3;
            this.func = function(){
                return this.val;
            }
        }
    };
};

then I would expect:

var obj = new objType();
console.log(obj.func());
console.log(obj.level1.func());
console.log(obj.level1.level.func());

for output:

1
2
3

However, only the first console.log exits before the script throw an error.

Is there a way to have helper methods in Javascript?

- edit -

My goal is to create a class that I can use to display a window in the middle of the screen, to display messages, questions (to get a yes / no answer) and forms. I thought a good way to structure this would be with helper methods, so that it could be referenced:

function box() {
    this.show = function(){
        //multiple sub methods here
    }
    this.hide = function(){
        //code to hide window here
    }
}

var aBox = new box();
aBox.show.message('the message');
aBox.hide();
aBox.show.question('the question');
aBox.hide();

- edit-- thanks @Sean Vieira

For completeness, I will put a modified version of my code here, using its solution:

function objType() {
    this.val = 1;
    this.func = function(){
        return this.val;
    }
    this.level1 = {
        val : 2,
        func : function(){
            return this.val;
        },
        level2 : {
            val : 3,
            func : function(){
                return this.val;
            }
        }
    }

var obj = new objType();
console.log(obj.func());
console.log(obj.level1.func());
console.log(obj.level1.level.func());

which outputs

1
2
3
+3
3

function Box() {
    this.show = function(){
       //your code goes here
       return this;

    },
    this.message = function(message){
       //code goes here
       return this;
    }
  }

var aBox = new Box();
aBox.message('the message').show()
+3

, this JavaScript , , new, Object, ( - .)

, "" ... that.

function objType() {
    var that = {}; // This is what `new` does behind the scenes
    // (Along with a few other things we won't replicate here).
    that.val = 1;
    that.func = function(){
        return that.val;
    }
    // Do additional things with `that` here
    return that;
}

, , "" ( , "" ), this .

, :

function log_this() {
    console.log(this, 
                    "Type:", typeof this, 
                    "IsObject:", this instanceof Object,
                    "IsFunction:", this instanceof Function);
}

log_this() // window (i.e. global scope)
log_this.apply({"some":"object"}) //  {"some":"object"}
log_this.apply(function(){}) // Anonymous function function(){}
var test_object = { fun: log_this };
test_object.log_this() // test_object
+2

This may work for level1:

var obj2 = new obj.level1();
console.log(obj2.func());
+1
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