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Passing variable into object method javascript

trying to get my head around objects, methods, closures, etc... in Javascript.
Can't see why this isn't working, some fundamental flaw in my thinking I guess. I'm expecting the val variable to be passed through to the addNote() function but it isn't. I thought that any variables declared outside of a function are available to that function, as long as they're not within another function. Is that not correct?
if(typeof(Storage) !== "undefined") {
console.log(localStorage);
var $input = $('#input'),
$submit = $('#submit'),
$list = $('#list'),
val = $input.val();
var noteApp = {
addNote : function(val) {
var item = val.wrap('<li />');
item.appendTo($list);
clearField();
},
clearField : function() {
$input.val = '';
},
delNote : function(note) {
}
};
$submit.on('click', function(){
noteApp.addNote();
});
} else {
}
I'm trying to learn how the pros manage to get their code so clean, concise and modular. I figured a note app would be a perfect start, shame I got stuck at the first hurdle...
Cheers.

There are several issues with the code in the question
defining an argument named val and not passing an argument to the function
when calling clearField() inside the object literal it's this.clearField()
You're only getting the value once, not on every click
val is a string, it has no wrap method
$input.val = ''; is not valid jQuery
I would clean it up like this
var noteApp = {
init: function() {
if (this.hasStorage) {
this.elements().events();
}
},
elements: function() {
this.input = $('#input');
this.submit = $('#submit');
this.list = $('#list');
return this;
},
events: function() {
var self = this;
this.submit.on('click', function(){
self.addNote();
});
},
hasStorage: (function() {
return typeof(Storage) !== "undefined";
})(),
addNote: function() {
this.list.append('<li>' + this.input.val() + '</li>');
this.clearField();
return this;
},
clearField: function() {
this.input.val('');
},
delNote : function(note) {
}
}
FIDDLE
Remember to call the init method
$(function() { noteApp.init(); });

In your call to addNote(), you don't pass any argument for the val, so it will be undefined:
noteApp.addNote();
// ^^ nothing
Pass the input (seems you want the jQuery object not the string value because of your val.wrap call):
noteApp.addNote($input);
When you declare the val in the function, it is scoped to that function and will only be populated if the function call passes a value for that argument. Even if you have another variable in an upper scope with the same name val, they are still differentiated. Any reference to val in the function will refer to the local val not the upper scope.

combine multiple functions with same code in jquery

Yes, I have thoroughly searched google and did not find anything that suits my requirement.
The code i have so far is at the link below:
http://jsfiddle.net/ZKwTY/4/
There are multiple onchange events which call almost the same code, i would like to combine them maybe in a comma separated fashion to call it only once.
something like this
(on1Change, on2Change, on3Change): function () {
this.loadData();
}
is this possible??
Note: these functions are bound to the controls via a framework over which i do not have control, i need to create these functions and the framework would bind these to the respective controls

or you can create your object like this
var ol = {
on1Change: this.loadData,
on2Change: this.loadData,
on3Change: this.loadData,
on4Change: this.loadData,
loadData: function () {
this.loadData1();
this.loadData2();
},
loadData1: function () {
alert('hi from loadData1');
},
loadData2: function () {
alert('hi from loadData2');
}
};
Then if you want to do it once, then declare a object
var ol = {
loadData: function () {
this.loadData1();
this.loadData2();
},
loadData1: function () {
alert('hi from loadData1');
},
loadData2: function () {
alert('hi from loadData2');
}
};// end of object
ol.on1Change = ol.on2Change = ol.on3Change = ol.on4Change = ol.loadData;
add all propteries dynamically after object declaration

use bind()
$("selector").bind(on1Change, on2Change, on3Change): function () {
this.loadData();
}.....

you can try somethig like this http://jsfiddle.net/s4VVY/
i.e. add methods after object create
[1,2,3,4,5].forEach(function(it){ol["on"+it+"Change"] = function(){this.loadData()}})
UPDATE
may be this help
var ol = (function(){
var o = {
loadData: function () {
this.loadData1();
this.loadData2();
},
loadData1: function () {
alert('hi from loadData1');
},
loadData2: function () {
alert('hi from loadData2');
}
}
o.on1Change=o.on2Change=o.on3Change=o.on4Change=function(){ this.loadData();};
return o;
})()
also you can make function bindFunc
function bindFunc(){
var obj = arguments[0],
handler = arguments[1],
properties = Array.prototype.slice.call(arguments,2);
for(var i in properties){
obj[properties[i]] = handler;
}
}
and call as
bindFunc(o,function(){this.loadData();},"on1Change","on2Change","on3Change","on4Change")

Deep nesting functions in JavaScript

I cannot find an proper example for the love of my life on how to do this or even if this is possible. Based on my pieced together understanding from fragments of exmaples, I have come up with the following structure
var t = function()
{
this.nestedOne = function()
{
this.nest = function()
{
alert("here");
}
}
}
t.nestedOne.nest();
However this is not working (obviously). I would greatly appreciate if someone could point me in the right direction!

That is simply done with:
var t = {
nestedOne: {
nest: function() {
alert('here');
}
}
};
Your code otherwise doesn't make sense. this inside function doesn't refer to the function itself, it refers to the object context that the function is invoked in. And you are not even invoking the functions in your code.
If I say obj.func() then this inside func will be obj for that call. So assigning this.asd = true will assign true to that object's "asd" property.
If you wanted to do a nested class, it looks very different:
ClassA = (function() {
function ClassA() {
}
ClassA.prototype.method1 = function() {
};
function ClassB() {
}
ClassB.prototype.method1 = function() {
};
return ClassA;
}())
only ClassA can now make instances of ClassB. This should achieve same goals as nested classes in java.

See http://jsfiddle.net/CstUH/
function t(){
function f(){
this.nest = function()
{
alert("here");
}
}
this.nestedOne = new f();
}
var myt=new t();
myt.nestedOne.nest()
Edit 1:
You can also use
new t().nestedOne.nest()
instead of
var myt=new t();
myt.nestedOne.nest()
(http://jsfiddle.net/CstUH/1/)
Edit 2:
Or even more condensed:
function t(){
this.nestedOne = new function(){
this.nest = function(){
alert("here");
}
}
}
new t().nestedOne.nest()
http://jsfiddle.net/CstUH/2/

In JS functions are prime class objects, and you can access them directly in the code [i.e. without using reflection or so].
The code you put inside t body would be performed when actually executing t:
t();
You wrote t.nestedOne,nest(), but t has no nestedOne property - you should do like this:
var t = {
nestedOne : {
nest : function()
{
alert("here");
}
}
};
t.nestedOne.nest(); ​
I advice you to have a trip on John Resig's Learning Advanced JavaScript tutorial, it was very enlightening for me.

A simple callback handler I wrote today as an example of how I do deep nesting. I apologize if it's not the bees knees when it comes to code style, it made the concept a little clearer for me.
function test () {
this.that = this;
this.root = this;
this.jCallback = new Array(new Array()); // 2d
this.jCallbackCount = -1;
this.str = "hello";
// Callback handler...
this.command = {
that : this, // let's keep a reference to who's above us on the food chain
root : this.root, // takes us back to the main object
// add : function() { var that = this; console.log(that.that.str); },
add : function(targetFnc, newFunc) {
var that = this;
var home = that.that; // pretty much root but left in as an example of chain traversal.
var root = this.root; // useful for climbing back up the function chain
// console.log(that.that.str);
home.jCallbackCount++;
// target, addon, active
home.jCallback[home.jCallback.length] = { 'targetFunc' : targetFnc, 'newFunc' : newFunc, 'active' : true, 'id': home.jCallbackCount};
console.log('cbacklength: ' + home.jCallback.length);
console.log('added callback targetFunction:[' + targetFnc + ']');
return home.jCallbackCount; // if we want to delete this later...
},
run : function(targetFnc) {
var that = this;
var home = that.that;
console.log('running callback check for: ' + targetFnc + ' There is : ' + (home.jCallbackCount + 1) + 'in queue.');
console.log('length of callbacks is ' + home.jCallback.length);
for(i=0;i < home.jCallback.length - 1;i++)
{
console.log('checking array for a matching callback [' + targetFnc + ']...');
console.log('current item: ' + home.jCallback[i]['targetFunc'] );
if( home.jCallback[i]['targetFunc'] == targetFnc )
{
// matched!
home.jCallback[i]['newFunc']();
}
// console.log(that.that.jCallback[i].targetFunction);
}
}
};
}
test.prototype = {
say : function () {
var that = this;
console.log('inside');
// that.command('doSay');
that.command.run('doSay');
console.log(that.str);
}
} // end proto
// BEGIN TESTING **************************************************************************
// BEGIN TESTING **************************************************************************
// BEGIN TESTING **************************************************************************
var testing = new test();
testing.command.add('doSay', function () { console.log('213123123'); } );
testing.command.add('doSay', function () { console.log('12sad31'); } );
testing.command.add('doSay', function () { console.log('asdascccc'); } );
testing.say();
live:
http://jsfiddle.net/Ps5Uf/
note: to view console output, just open inspector in chrome and click on the "console" tab.

JavaScript refer to a method inside a method?

Ok, just solved one problem where this refered to the wrong scope. Now I have another problem.
So I want to call a method that is inside a method. But I do not know how, check this source:
function someObj() {
var self = this;
this.someMethod1 = function() {
var elementBtn = document.getElementById('myBtn');
elementBtn.onclick = function() {
self.someMethod2.methodMethod();
//I want this.someMethod2.methodMethod() to be called
//...but I get an big error instead. Is it even possible?
//this.someMethod2() works fine.
};
};
this.someMethod2 = function() {
this.methodMethod = function() {
alert('THIS IS THE ONE I WANTED!');
};
alert('NO, NOT THIS!');
};
}
Error msg:
Uncaught TypeError: Object function () { ...

With your code, someMethod2 would need to execute first for the function expression to be assigned. Even then, it would be assigned to the parent instance.
Bearing in mind that all functions are objects in JavaScript, this is what you want instead:
this.someMethod2 = function() {
alert('NO, NOT THIS!');
};
this.someMethod2.methodMethod = function() {
alert('THIS IS THE ONE I WANTED!');
};

You are trying to use an object accessor on a function. If you want it to work in this way, you need to return an object literal from your call to the "outer" function.
this.someMethod2 = function() {
return {
methodMethod: function() {
alert('THIS IS THE ONE I WANTED!');
}
}
};
You can then chain the call. self.someMethod2().methodMethod();

While this is not directly possible, you can pass a "command" to the outer function to tell it to execute the inner function. But, are you sure this is what you really need? Perhaps you should use objects instead of functions here. But here's the "command" way:
this.someMethod2 = function(cmd) {
var methodMethod = function() {
alert('THIS IS THE ONE I WANTED!');
};
if (cmd === "methodMethod") {
methodMethod();
return;
}
alert('NO, NOT THIS!');
};

function someObj() {
var self = this;
this.someMethod1 = function () {
var elementBtn = document.getElementById('myBtn');
elementBtn.onclick = function () {
self.someMethod2().methodMethod();
};
};
this.someMethod2 = function () {
this.methodMethod = function () {
alert('THIS IS THE ONE I WANTED!');
};
//return this for chain method.
return this;
};
}

trying
function someObj() {
var self = this;
this.someMethod1 = function() {
var elementBtn = document.getElementById('myBtn');
elementBtn.onclick = function() {
self.someMethod2().methodMethod();
};
this.someMethod2 = function() {
this.methodMethod = function() {
alert('THIS IS THE ONE I WANTED!');
};
alert('NO, NOT THIS!');
return this;
};
}
Also if you use prototype then
function someObj() {
var self = this;
this.someMethod1 = function() {
var elementBtn = document.getElementById('myBtn');
elementBtn.onclick = function() {
self.someMethod2.methodMethod();//['methodMethod']();
};
};
this.someMethod2 = function() {
};
this.someMethod2.methodMethod = function() {
alert('THIS IS THE ONE I WANTED!');
};
};
But the method methodMethod is static

Choose which set of methods an object has, based on argument during object creation - JavaScript

I have searched and read for a few hours yet I still cant understand the basic design pattern for creating a new object that has a choice of different methods (of the same name) that is set dependant on one of the arguments. here's some code to explain what I am trying to do.
All advice and alternative approaches welcome. I hope someone can emancipate me form this cloud of ignorance.
Thanks
function BaseConstructor(whichMethods) {
if (whichMethods==='a') {
// do something to incorporate methodSetA
}
else if (whichMethods==='b') {
// do something to incorporate methodSetB
}
this.init();
};
var methodSetA = {
init: function() {
// do initialisation A way
},
speak: function() {
alert('i speak AAA way')
}
};
var methodSetB = {
init: function() {
// do initialisation B way
},
speak: function(){
alert('i got BBB all the way')
}
};
thing = new BaseConstructor('b');
// b is an instance of BaseConstructor and has done the bWay init() function
thing.speak() // return alert 'i got BBB all the way'

You can do it like this using a factory function (a regular function that creates the appropriate object for you):
function BaseConstructor(whichMethods) {
var elem;
if (whichMethods==='a') {
elem = new MethodSetA();
} else if (whichMethods==='b') {
elem = new MethodSetB();
} else {
// figure out what to do here if whichMethods is neither of the previous options
}
elem.init();
return(elem);
};
And invoke it as a regular function call:
var thing = BaseConstructor('b');
thing.speak();
Note: there is no use of new with BaseConstructor() as it's a regular function call.

Well, to do it your way using "method sets," you can iterate and copy into this (here's a demo):
function copy(source, destination) {
for(var x in source) {
if(source.hasOwnProperty(x)) {
destination[x] = source[x];
}
}
}
function BaseConstructor(whichMethods) {
if(whichMethods === 'a') {
copy(methodSetA, this);
} else if(whichMethods === 'b') {
copy(methodSetB, this);
}
this.init();
}
Personally, though, I'd prefer to assign directly to this.

You are looking for factory pattern.
Example:
function objectFactory(whichMethods) {
if (whichMethods==='a') {
return new objectSetA();
}
else if (whichMethods==='b') {
return new objectSetB()
}
};
function objectSetA() {
this.init = function() {
// do initialisation A way
},
this.speak = function() {
alert('i speak AAA way')
}
};
function objectSetB() {
this.init = function() {
// do initialisation B way
},
this.speak = function(){
alert('i got BBB all the way')
}
};
var thing = objectFactory('b');
thing.speak();