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break large public javascript functions into smaller private functions

I have JavaScript class which have huge functions which are very difficult to maintain.
The 2 public functions are called at start and then on click. I want to create private functions inside these public functions say break into into some private functions scope to these public methods.
var searchResultView;
var SearchResultView = function () {
me = this;
this.init = function () {
// huge code
}
this.Search = function () {
// huge code
}
}
jQuery(function () {
searchResultView = new SearchResultView();
searchResultView.init();
searchResultView.Search();
}
What will best way to achieve this. I tried to use below approach but i think this nested function will not work well.
var searchResultView;
function searchResultView() {
me = this;
this.init = function () {
var declareControls = function () {}
var addEvents = function () {}
var fillControls = function () {}
declareControls();
addEvents();
fillControls();
}
this.Search = function () {
var validateAndCreateCriteria = function () {
if (!validateAandGetLocation()) {
alert("invalid location");
return false;
}
if (!validateAandGetCategory()) {
alert("choose search type");
return false;
}
var validateAandGetLocation = function () {}
var validateAandGetCategory = function () {}
}
validateAndCreateCriteria();
}
}
jQuery(function () {
searchResultView = new searchResultView();
searchResultView.init();
});

If I understood correctly, you should have the functions something like this:
var foo = (function() {
var privateBar = function() { // private function
},
privatefooBar = function() { // private function
};
return {
publicFoo : function() { //public function
/* use privateBar and privatefooBar functions here */
}
};
})();
Later you can access publicFoo function by using
foo.publicFoo();
But you can't access the inside functions which are privateBar() and privatefooBar() directly because they are private functions.
Updated Fiddle

Breaking up the function is easy:
function f(..) {
// many lines here
return ret_f;
}
if equivalent to
function f {
function f1(..) {
// not so many lines here
}
function f2(..) {
// not so many lines here
}
var ret_f1 = f1(..);
var ret_f2 = f2(..);
// calculate ret_f from ret_f1 and ret_f2
return ret_f;
}
or if you prefer this style using anonymous functions
function f {
var f1 = function(..) {
// not so many lines here
};
var f2 = function(..) {
// not so many lines here
};
var ret_f1 = f1(..);
var ret_f2 = f2(..);
// calculate ret_f from ret_f1 and ret_f2
return ret_f;
}
I fear however your real question is specific to your existing code and is about what useful smaller functions to extract there and how to combine them.
For this one would need to have your full code and understand it. That might be a bit much for this QA format.

javascript const in javascript library

I am trying to write a small javascript library as shown below. What I really want is when I call
console.log(tnd().pv);
it should output same number and not generate new number everytime. I know the issue is it calls Math.random everytime I console log. But how can I do so that it outputs same number?
(function () {
var tnd = function() {
return new tnlib();
};
var tnlib = function() {
this.version = function(){
console.log('1.0');
};
this.pv = Math.random()*10000000000000000;
};
if(!window.tnd) {
window.tnd = tnd;
}
})();

Don't execute Math.random() on each invocation of tnlib, but as a static variable:
(function () {
function tnd() {
return new tnlib();
}
function tnlib() {
}
tnlib.prototype.version = function(){
console.log('1.0');
};
tnlib.prototype.pv = Math.random()*10000000000000000;
if (!window.tnd) {
window.tnd = tnd;
}
}());
(or, if you really need to make pv an instance property):
var staticPv = Math.random()*10000000000000000;
function tnlib() {
this.pv = staticPv;
…
}

call javascript function after another

Can you please help answering this. Please not the contraints.
var myLib = {
var callback_one = function (result_from_web_service) {
console.log('callback_one');
};
var callback_one = function (result_from_web_service) {
console.log('callback_two');
};
var init = function () {
console.log('initializing...');
async_call_one(callback_one);
async_call_two(callback_two);
};
var doStuff = function () {
console.log('doStuff is called');
};
};
// User of my library
myLib.init();
myLib.doStuff();
// output
initializing...
doStuff is called
callback_one
callback_two
// What i need:
initializing...
callback_one
callback_two
doStuff is called
Constraint:
calling myLib.init shall not end up calling myLib.doStuff. i.e. myLib.init should be independent of myLib.doStuff
myLib.doStuff() should be called after myLib.init() and its callbacks are returned.
Thanks,

//You must change your API so init is async
//There is no way to have it wait until all initialization is done before it retuns
var init = function (initDone) {
console.log('initializing...');
var n = 0;
function serviceDone(){
n++;
if(n >= 2){ initDone() }
}
async_call_one(function(x){ callback_one(x); serviceDone() });
async_call_two(function(x){ callback_two(x); serviceDone() });
};
// User of my library
myLib.init(function(){
myLib.doStuff();
})
The way I parallelized those calls is very ad-hoc s not the most maintainable (there I need to keep the calls to serviceDone and the value of N in sync).. In the long run I would recommend using one of the many JS async programming libs out there.

hugomg has a good answer.
Yet I think it is really specific and could benefit a sort of workflow implementation, like this (approximately...):
function void() {}
var myLib = {
var g_flow = [];
g_flow[this.init] = [];
g_flow[this.init]["whendone"] = this.callback_one;
g_flow[this.init]["done"] = false;
g_flow[this.callback_one] = [];
g_flow[this.callback_one]["whendone"] = this.callback_two;
g_flow[this.callback_one]["done"] = false;
g_flow[this.callback_two] = [];
g_flow[this.callback_two]["whendone"] = this.doStuff;
g_flow[this.callback_two]["done"] = false;
g_flow[this.doStuff] = [];
g_flow[this.doStuff]["whendone"] = void;
g_flow[this.doStuff]["done"] = false;
var callback_one = function (result_from_web_service) {
console.log('callback_one');
};
var callback_one = function (result_from_web_service) {
console.log('callback_two');
};
var init = function () {
console.log('initializing...');
};
var doStuff = function () {
console.log('doStuff is called');
};
var flow_onward(hwnd) {
async_call(function(){ hwnd(); myLib.flow_onward(g_flow[hwnd]["whendone"]); });
}
flow_onward(this.init);
};
// User of my library
myLib.init();
myLib.doStuff();
Doing this way you can ensure the sequentiality and expand the numbers of callback as much as you want.
ps: this code has not been tested

JavaScript: Accessing Nested Objects

The code looks like this
function Scripts() {this.FindById = function (id) {
this.FindById.constructor.prototype.value = function () {
return document.getElementById(id).value;
}}}
var Control = new Scripts();
Now when i say Control.FindById("T1").value(). I am not able to get the textInput("T1")'s value.

It seems that your code is a bit more complicated then it should be ;-)
Personally I would write it this way (not tested):
function Scripts() {
this.findById = function(id) {
var el = document.getElementById(id);
return {
value: function() {
return el.value;
}
}
}
}
The findById() now closes over a node and returns an interface that can return its value.
Also, your idea sounds a lot like Singleton, so you wouldn't even need the extra Scripts constructor:
var Control = {
findById: function(id) {
var el = document.getElementById(id);
return {
value: function() {
return el.value;
}
}
}
}
Working example: http://jsfiddle.net/YYkD7/

Try this:
function Scripts() {this.FindById = function (id) {
this.FindById.constructor.prototype.value = function () {
return document.getElementById(id).value
}}}
You didn't close the last "}" :-)

Resolve function pointer in $(document).ready(function(){}); by json string name

I have a json object retrieved from server in my $(document).ready(...); that has an string that I would like to resolve to a function also defined within $(document).ready(...); so, for example:
$(document).ready(function{
$.getJSON(/*blah*/,function(data){/*more blah*/});
function doAdd(left,right) {
return left+right;
}
function doSub(left,right) {
return left-right;
}
});
with json string:
{"doAdd":{"left":10,"right":20}}
One way I thought about was creating an associative array of the function before loading the json:
var assocArray=...;
assocArray['doAdd'] = doAdd;
assocArray['doSub'] = doSub;
Using eval or window[](); are no good as the function may not be called for some time, basically I want to link/resolve but not execute yet.

Change your JSON to
{method: "doAdd", parameters : {"left":10,"right":20}}
Then do
var method = eval(json.method);
// This doesn't call it. Just gets the pointer
Or (haven't tried this)
var method = this[json.method]

How about something like this?
$(function(){
// Function to be called at later date
var ressolvedFunc = null;
// Ajax call
$.getJSON(/*blah*/,function(data){
// Generate one function from another
ressolvedFunc = (function(data) {
var innerFunc;
var left = data.left;
var right = data.right;
// Detect action
for (action in data) {
if (action == "doAdd")
innerFunc = function() {
return left + right;
};
else
innerFunc = function() {
return left - right;
};
}
return innerFunc;
})(data);
});
});
The anonymous function returns fresh function, with the new values stored within the enclosure. This should allow you to call the function at later date with the data previously retrieved from the GET request.
Rich

try this:
var doX = (function() {
var
data = [],
getDo = function(action) {
for(var d in data) {
if (data[d][action]) {
return data[d];
}
}
return null;
};
return {
set: function(sdata) {
data.push(sdata);
},
doAdd: function() {
var add = getDo("doAdd");
if (!add)
return 0;
return add.doAdd.left + add.doAdd.right;
},
doSub: function() {
var sub = getDo("doSub");
if (!sub)
return 0;
return sub.doAdd.left + sub.doAdd.right;
}
};
})();
$(document).ready(function{
$.getJSON(/*blah*/,function(data){ doX.set(data); });
});