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Selectize Ajax Callbacks

The selectize dropdown I have on the page gets populated from an AJAX call via the following. What's not working is I need to run some additional code right after the callback() method invocation, but it never continues into the rest of the callback. For instance, the following in the success callback doesn't run the additional code identified:
var $ddl = $("#ContactID");
var control = $ddl[0].selectize;
control.load(function () {
$.ajax({
url: "validURL",
type: "post",
dataType: "json",
data: {
id: recordID
},
error: function () {
alert("Error retrieving data");
callback();
},
success: function (result) {
callback(result.data);
//Does not get called below
loadAdditionalInformation(recordID);
}
});
});
However, if I do this, it works:
success: function (result) {
window.setTimeout(function() {
callback(result.data);
}, 0);
loadAdditionalInformation(recordID);
}
I need to call a method at the point the list is loaded, so I am not sure I want to continue with that, so why is the success callback aborting after the callback() method call.

load expects two parameters, query and callback.
$('#ContactID').selectize({
....
load : function (query, callback) {
$.ajax({
....
success : function(res) {
callback(res.data);
doOtherThings(res);
}
});
}
});
Your code does not pass any of those parameters, so it is very likely that when success() is called, the callback() function is undefined.
I suggest put breakpoint and inspect it.

AJAX Call that Returns Javascript Variable

Struggling to return a AJAX Result Variable back to JavaScript
Note that the $.ajax call below is synchronous (async: false).
Ajax Call
function getState(callback) {
$.ajax({
url: 'getSearchState.php',
data: { "state": callback },
type: 'GET',
async: false,
success: function(result){
alert(result);
},
error: function(result) {
alert(result);
}
});
}
Ajax PHP
<?php
// Database Setup and Query
while ($row = $xxxxx->fetch(PDO::FETCH_ASSOC)) {
$StateVal = $row['State'];
}
return $StateVal;
?>
Javascript Calling the Function
var URL = District.trim();
var StateURL = getState(URL);
It gets the URL vairable from the function just fine, but doesnt return anything.
Any help would be great!

There are problems with that code both client-side and server-side.
Client-side:
Your getState is never returning anything, so it's no surprise that you don't see anything other than undefined for StateURL.
Don't use synchronous ajax. It makes for horrible UX. But if you really, really want to keep using it, here's how you would:
function getState(state) {
var result; // <=== Where we'll put our result
$.ajax({
url: 'getSearchState.php',
data: {"state": state},
type: 'GET',
async: false,
success: function(data) {
// Remember the result;
result = data;
},
error: function() {
result = /*...whatever you want to use to signal an error */;
}
});
// Return the result
return result;
}
Note that I changed the name of the argument to state, since it's not a callback.
But again, don't use synchronous ajax. Instead, use a callback or promises.
Promise: $.ajax already returns a promise, so just return that directly:
function getState(state) {
var result; // <=== Where we'll put our result
$.ajax({
url: 'getSearchState.php',
data: {"state": state},
type: 'GET',
async: false,
success: function(data) {
// Remember the result;
result = data;
},
error: function() {
result = /*...whatever you want to use to signal an error */;
}
});
// Return the result
return result;
}
Note that I changed the name of the argument to state, since it's not a callback.
But again, don't use synchronous ajax. Instead, use a callback or promises.
Promise:
function getState(state) {
return $.ajax({
url: 'getSearchState.php',
data: {"state": state},
type: 'GET'
});
}
Usage:
getState(URL)
.done(function(StateURL) {
// Use it
})
.fail(function() {
// Failed
});
Callback:
function getState(state, callback) {
$.ajax({
url: 'getSearchState.php',
data: {"state": state},
type: 'GET',
success: function(data) {
// Call the callbback with the result
callback(data);
},
error: function() {
// Call the callback with an error
callback(/*...whatever you want to use tosignal an error */);
}
});
}
Usage:
getState(URL, function(StateURL) {
// Use it, check for error
});
Server-side:
As RiggsFolly pointed out, you're returning a string from your PHP code. But that won't output it. To use it client-side, you need to output it (e.g., echo and similar). And to make it easily consumed by the JavaScript, you probably want to json_encode it to ensure that it's in a format JavaScript can understand:
echo json_encode($stateVal);
Then in your success (or done) function, use JSON.parse on it:
result = JSON.parse(data);

this is jQuery and in this case you can specify context and in success function set variables on that context.... a bit crude solution but it will works. Also take a look on arrow functions and promises from ES6, it can help you a lot and give you new perspective about whole problem.
And one main thing!! Ajax is async by default so you need somehow notify your StateURL when data will be ready (here again promise at you service)

Passing GET data from one function to another

I'm trying to pass some data from one function to another. I have made a successful AJAX call and got the data. But what I can't figure out now is how to pass that data to another function.
'use strict'
$(document).ready(function() {
console.log('Page Ready');
changeColor();
getData();
});
function getData(data) {
var root = 'http://jsonplaceholder.typicode.com',
data;
data = $.ajax ({
url: root + '/posts/1',
type: 'GET',
success: function(data) {
console.log(data.body);
}
});
}
function changeColor(data) {
$('button').on('click', function() {
$('.classy').toggleClass('blue');
$('.classy').append(data.body);
});
}
Is someone able to advise how I can get the data from getData and pass it to changeColour?

Just call the changeColor method in the ajax success and pass the data. Removed the data variable from getData as there was no need for it.
'use strict'
$(document).ready(function() {
console.log('Page Ready');
changeColor();
getData();
});
function getData() {
var root = 'http://jsonplaceholder.typicode.com';
$.ajax ({
url: root + '/posts/1',
type: 'GET',
success: function(data) {
console.log(data.body);
changeColor(data); //Just call the method here
}
});
}
function changeColor(data) {
$('button').on('click', function() {
$('.classy').toggleClass('blue');
$('.classy').append(data.body);
});
}

Merely invoke your changeColor() function from success: function.
function getData(data) {
var root = 'http://jsonplaceholder.typicode.com',
data = $.ajax ({
url: root + '/posts/1',
type: 'GET',
success: function(data) {
console.log(data.body);
changeColor(data);
}
});
}
Note that I dropped your simple data; line, which has no sense.

You could put the changeColor function into the success call of the getData function.
function getData(data) {
var root = 'http://jsonplaceholder.typicode.com',
data;
data = $.ajax ({
url: root + '/posts/1',
type: 'GET',
success: function(data) {
console.log(data.body);
changeColor(data);
}
});
}

You basically have two options: call the changeColor function from within the success function, or in your success function store the data in a variable that can be accessed elsewhere (either directly by changeColor or passed into changeColor).
The second option can be achieved by either accessing a global variable (not really a good idea), or passing in an object that will then be passed into changeColor. Which one is best really depends upon your usage.

Jquery When and Deferred object, broken function flow

I am using $.when and .done to make sure that the close window happens after the data is saved. But, this doesn't seem to work as expected.
The workflow is that, user clicks on a button "Save and Close", which should save the data first, trigger print and close the window. But the save data and close window happens at the same time which makes the print fail.
I have read about when..then and deferred object. Tried to implement it here the following code, sometimes it work but most of the time it would break.
$("#btnSaveAndClose").click(function (event) {
$.when(zSaveSomeData()).done(function (value) {
zCloseMyWindow();
});
});
function zSaveSomeData() {
return zSaveMasterData(masterdata, function () {
return zSaveDetailData();
});
};
function zSaveMasterData(masterdata, fnAfterSave) {
return $.ajax({
type: 'POST',
contentType: 'application/json',
url: '/api/masterdata/',
data: JSON.stringify(masterdata),
success: function (data) {
fnAfterSave();
}
});
};
function zSaveDetailData() {
var selectedDataGroups;
// some logic here
zSaveDetails(selectedDataGroups);
};
function zSaveDetails(selectedDataGroups) {
var deferred = $.Deferred();
$.ajax({
type: 'POST',
contentType: 'application/json',
url: '/api/detaildata/',
data: JSON.stringify(selectedDataGroups),
success: function (data) {
var printableGroupIDs = [];
$.each(data, function () {
if (this.IsPrintable)
printableGroupIDs.push(this.ID);
});
if (printableGroupIDs.length > 0) {
zPrintGroups(printableGroupIDs);
}
deferred.resolve('done');
}
});
zAuditSave();
return deferred.promise();
};
function zPrintGroups(newGroupIDs) {
// calls external program to print groups
};
function zCloseWindow() {
window.close();
};
function zAuditSave() {
$.ajax({
type: 'POST',
contentType: 'application/json',
url: '/api/audit'
success: function (data) {
}
});
};
Only thing is that the save calls other methods inside to same master and details data. There are couple of ajax calls too. An unusual thing is that after the data is saved, there is a call to VB code that actually triggers a Print. I am so confused on why would close window fire before the other methods are executed. Any help would be appreciated.

For me the code is overly divided into functions, with some doing little more than fronting for others.
I would prefer to see the click handler as a comprehensive master routine which sequences three promise-returning functions zSaveMasterData(), zSaveDetails() and zAuditSave(), then closes the window. Thus, some of the current functions will be subsumed by the click handler.
$("#btnSaveAndClose").click(function(event) {
zSaveMasterData(masterdata).then(function() {
var selectedDataGroups;
/* some logic here */
var detailsSaved = zSaveDetails(selectedDataGroups).then(function(data) {
var printableGroupIDs = $.map(data, function (obj) {
return obj.IsPrintable ? obj.ID : null;
});
if (printableGroupIDs.length > 0) {
// calls external program to print groups
}
});
// Here, it is assumed that zSaveDetails() and zAuditSave() can be performed in parallel.
// If the calls need to be sequential, then the code will be slightly different.
return $.when(detailsSaved, zAuditSave());
}).then(function() {
window.close();
});
});
function zSaveMasterData(masterdata) {
return $.ajax({
type: 'POST',
url: '/api/masterdata/',
contentType: 'application/json',
data: JSON.stringify(masterdata),
});
};
function zSaveDetails(selectedDataGroups) {
return $.ajax({
type: 'POST',
contentType: 'application/json',
url: '/api/detaildata/',
data: JSON.stringify(selectedDataGroups)
});
};
function zAuditSave() {
return $.ajax({
type: 'POST',
contentType: 'application/json',
url: '/api/audit'
});
};
Note the returns in the three functions with ajax calls. These returns are vital to the sequencing process.
A potentially bigger issue, not addressed in the question (nor in this answer) is how to recover from errors. Presumably, the database will be inconsistent if the sequence of saves was to fail part way through. It may well be better to ditch this client-side sequencing approach in favour of a server-side transaction that the client sees as a single operation.

The problem here is your code doesn't depend on when fnAfterSave() has completed.
Short answer: don't mix success methods, callbacks, and promises - use one pattern and stick to it - and the easiest pattern to use is promises.
$("#btnSaveAndClose").click(function (event) {
zSaveSomeData().then(function() { zCloseMyWindow(); });
});
function zSaveSomeData() {
return zSaveMasterData(masterdata).then(function(data) { zSaveDetailData() });
};
function zSaveMasterData(masterdata) {
return $.ajax({
type: 'POST',
contentType: 'application/json',
url: '/api/masterdata/',
data: JSON.stringify(masterdata)
});
//remove success callback here as it breaks the chaining
};

It seems like your problem is that you are doing asynchronous things inside an ajax success callback. The promise returned by $.ajax still resolves immediately after the response is received - and executes your done callback before the asynchronous zSaveDetailData() has finished.
So, to chain asynchronous actions, always use then. Use it even for synchronous actions, it makes the sequence clear.
Don't use success callbacks when you're working with promises. You also don't need deferreds. You might want to have a look at these generic rules as well, especially that you never must forget to return promises from async functions that you want to await.
$("#btnSaveAndClose").click(function (event) {
zSaveSomeData().then(zCloseMyWindow);
});
function zSaveSomeData() {
return zSaveMasterData(masterdata).then(zSaveDetailData);
}
function zSaveMasterData(masterdata) {
return $.ajax({
type: 'POST',
contentType: 'application/json',
url: '/api/masterdata/',
data: JSON.stringify(masterdata),
});
}
function zSaveDetailData() {
var selectedDataGroups;
// some logic here
return zSaveDetails(selectedDataGroups);
// ^^^^^^
}
function zSaveOrderGroups(selectedDataGroups) {
return $.ajax({
// ^^^^^^
type: 'POST',
contentType: 'application/json',
url: '/api/detaildata/',
data: JSON.stringify(selectedDataGroups)
}).then(function(data) {
// ^^^^^^^^^^^^^^^^^^^^^^
var printableGroupIDs = [];
$.each(data, function () {
if (this.IsPrintable)
printableGroupIDs.push(this.ID);
});
if (printableGroupIDs.length > 0) {
return zPrintGroups(printableGroupIDs);
// ^^^^^^
}
}).then(zAuditSave);
// ^^^^^^^^^^^^^^^^^
}
function zPrintGroups(newGroupIDs) {
// calls external program to print groups
}
function zCloseWindow() {
window.close();
}
function zAuditSave() {
return $.ajax({
// ^^^^^^
type: 'POST',
contentType: 'application/json',
url: '/api/audit'
});
}

How to use requirejs to work with ajax callbacks?

If I have to leverage niceties of jQuery AJAX API and set my own custom settings for each ajax call my app makes like below:
Say I have a page which displays employee information within table by making ajax calls to some API.
define(["jQuery"], function($) {
var infoTable = function (options) {
function init() {
// Provide success callback
options.success_callback = "renderData";
getData();
}
function renderData() {
// This callback function won't be called as it is not
// in global scope and instead $.ajax will try to look
// for function named 'renderData' in global scope.
// How do I pass callbacks defined within requirejs define blocks?
}
function getData() {
$.ajax({
url: options.apiURL,
dataType: options.format,
data: {
format: options.format,
APIKey: options.APIKey,
source: options.source,
sourceData: options.sourceData,
count: options.count,
authMode: options.authMode
},
method: options.method,
jsonpCallback: options.jsonpCallback,
success: options.success_callback,
error: options.error_callback,
timeout: options.timeout
});
}
}
return {
init: init
}
}
How do I achieve this?
I know we can use JSONP request as require calls but that restricts me to using jsonp, making GET requests and all other features $.ajax offers.

This example would let you either use a default success callback, or provide an override, using:
success: options.successCallback || renderData
(The example uses jsfiddle rest URLs - this fact is unimportant, and stripped out the data object to keep the example short)
define("mymodule", ["jquery"], function($) {
function renderData() {
console.log("inside callback");
}
function getData(options) {
$.ajax({
url: options.apiURL,
dataType: options.format,
method: options.method,
jsonpCallback: options.jsonpCallback,
success: options.successCallback || renderData,
error: null,
timeout: options.timeout
});
}
return {
getData: getData
}
});
require(["mymodule"], function(m) {
console.log(m, m.getData({
apiURL: "/echo/json/"
}));
console.log(m, m.getData({
successCallback: function() { console.log("outside callback"); },
apiURL: "/echo/json/"
}));
});
Would print:
GET http://fiddle.jshell.net/echo/json/ 200 OK 263ms
Object { getData=getData()} undefined
GET http://fiddle.jshell.net/echo/json/ 200 OK 160ms
Object { getData=getData()} undefined
inside callback
outside callback