Develop Reference

JavaScript/jQuery callback using Ajax

I'm having trouble with my functions running before Ajax requests (the first to a local JSON, the second to an online resource) have finished.
In this example I want countTheMovies to run at the end after my application has got all the information it needs and populated the divs. Instead it's running straight away.
I tried to delay it using an if condition, but with no joy. I've also tried with callbacks, but think I must be getting those wrong (I'm assuming callbacks are the answer). I'm aware of timed delays, but because in the actual project I'm sourcing 250+ movies (and because a timed delay seems like cheating) I thought I'd ask here instead.
Can anyone recommend JavaScript or jQuery code to fix this problem?
$(function(){
getMovieList();
});
function getMovieList() {
$.ajax({
url: "movielist.json",
type: "GET",
dataType: "JSON",
success: function(data) {
for (var i = 0; i < data.length; i++) {
var title = data[i].title.toLowerCase().split(" ").join("+");
var year = data[i].year;
i === data.length - 1
? getMovieInfo(title, year, true)
: getMovieInfo(title, year, false);
}
}
});
}
function getMovieInfo(title, year, isLast) {
$.ajax({
url: "https://www.omdbapi.com/?t=" + title + "&y=" + year + "&plot=short&r=json",
type: "GET",
crossDomain: true,
dataType: "JSON",
success: function(val) {
if (!val.Error) {
movie = title.replace(/[^a-z0-9\s]/gi, '');
$("#app").append(
// appending info to divs
);
}
}
});
if (isLast) countTheMovies();
};
function countTheMovies() {
$("#app").append("There are " + $(".movie").length + " movies.");
}
A plunker of my failings: https://plnkr.co/edit/0mhAUtEsaOUWhkZMJqma?p=preview

You've almost got it!
The same way that you call getMovieInfo in the success callback of getMovieList, you should be calling countTheMovies in the success callback of getMovieInfo.

As Jacob said above, move the countTheMovies call inside the AJAX request.
$(function(){
getMovieList();
});
function getMovieList() {
$.ajax({
url: "movielist.json",
type: "GET",
dataType: "JSON",
success: function(data) {
for (var i = 0; i < data.length; i++) {
var title = data[i].title.toLowerCase().split(" ").join("+");
var year = data[i].year;
i === data.length - 1
? getMovieInfo(title, year, true)
: getMovieInfo(title, year, false);
}
}
});
}
function getMovieInfo(title, year, isLast) {
$.ajax({
url: "https://www.omdbapi.com/?t=" + title + "&y=" + year + "&plot=short&r=json",
type: "GET",
crossDomain: true,
dataType: "JSON",
success: function(val) {
if (!val.Error) {
movie = title.replace(/[^a-z0-9\s]/gi, '');
$("#app").append(
// appending info to divs
);
if (isLast) countTheMovies();
}
}
});
};
function countTheMovies() {
$("#app").append("There are " + $(".movie").length + " movies.");
}

Just put your countTheMovies() logic inside of the success callback of the AJAX request in getMovieInfo if you want it to run on success.

You can call your countTheMovies() function from inside the success field of your Ajax call. This way it will make the function call when you intend it to.

Try out this
$(function(){
getMovieList();
});
function getMovieList() {
$.when( $.ajax({
url: "movielist.json",
type: "GET",
dataType: "JSON",
success: function(data) {
for (var i = 0; i < data.length; i++) {
var title = data[i].title.toLowerCase().split(" ").join("+");
var year = data[i].year;
i === data.length - 1
? getMovieInfo(title, year, true)
: getMovieInfo(title, year, false);
}
}
}) ).then(function( data, textStatus, jqXHR ) {
countTheMovies();
});
}
function getMovieInfo(title, year, isLast) {
$.ajax({
url: "https://www.omdbapi.com/?t=" + title + "&y=" + year + "&plot=short&r=json",
type: "GET",
crossDomain: true,
dataType: "JSON",
success: function(val) {
if (!val.Error) {
movie = title.replace(/[^a-z0-9\s]/gi, '');
$("#app").append(
// appending info to divs
);
}
}
});
};
function countTheMovies() {
$("#app").append("There are " + $(".movie").length + " movies.");
}

Issue with newElements function

I have a vote function in one of my projects. Please see following code.
$(function () {
$(".vote").click(function () {
var id = $(this).data("id");
var name = $(this).data("name");
var dataString = 'id=' + id;
//var dataId = id;
var parent = $(this);
if (name == 'up') {
$(this).fadeIn(200).html;
$.ajax({
type: "POST",
url: "vote_up.php",
data: dataString,
cache: false,
success: function (html) {
parent.parent().find(".display-vote").html(html);
}
});
} else {
$(this).fadeIn(200).html;
$.ajax({
type: "POST",
url: "vote_down.php",
data: dataString,
cache: false,
success: function (html) {
parent.parent().find(".display-vote").html(html);
}
});
}
return false;
});
});
and I'm using jQuery infinite scroll to load rest of the pages/posts. I'm using following code in main page and second page which i load rest of the data
('#left').infinitescroll({
navSelector: '#page-nav', // selector for the paged navigation
nextSelector: '#page-nav a', // selector for the NEXT link (to page 2)
itemSelector: '.post-box', //
}, function (newElements, data, url) {
$(".vote").click(function () {
var id = $(this).data("id");
var name = $(this).data("name");
var dataString = 'id=' + id;
//var dataId = id;
var parent = $(this);
if (name == 'up') {
$(this).fadeIn(200).html;
$.ajax({
type: "POST",
url: "vote_up.php",
data: dataString,
cache: false,
success: function (html) {
parent.parent().find(".display-vote").html(html);
}
});
} else {
$(this).fadeIn(200).html;
$.ajax({
type: "POST",
url: "vote_down.php",
data: dataString,
cache: false,
success: function (html) {
parent.parent().find(".display-vote").html(html);
}
});
}
return false;
});
});
Issue is after 2nd 3rd or any other page load, vote function is triggering twice. How can I fix this issue. Any help will be appreciated.

Maybe if you unbind the click event and then bind it
function(newElements, data, url){
$(".vote").unbind( "click" );
$(".vote").click(function() {

You need to unbind the click event before binding it again.
[...]
$(".vote").unbind('click').click(function()
[...]
or
[...]
$(".vote").off('click').click(function()
[..]
depending on the version of jQuery you are using.

Javascript status loop

Ok, simple thing in javascript that I could not solve even searching on the web. I guess I even found the right thing but could not put on the right place.
This code tells me if a stream is online or offline. But how do I do to the status and keep updating every 5 seconds?
$(function () {
$.ajax({
type: 'GET',
url: "http://xmychannelx.api.channel.livestream.com/2.0/livestatus.json?callback=?",
dataType: 'jsonp',
success: function (jsonp) {
// parse the JSON data on success
var channel = eval(jsonp);
liveChannel = channel.channel.isLive;
if (liveChannel == true) {
document.getElementById('mydiv').innerHTML = '<p style="color: #00FF00">Online!</p>';
} else {
document.getElementById('mydiv').innerHTML = '<p style="color: #C0C0C0">Offline!</p>';
}
}
});
});

Example :
var myAjaxCall = function() {
$.ajax({
type: "GET",
url: options.feedUrl,
dataType: "xml",
async:options.sync,
success: function(xml) {
// todo
}
};
var ResInterval = window.setInterval(myAjaxCall, 60000); // 60 seconds
To Stop:
window.clearInterval(ResInterval);

use set time out function
setTimeout(function(){
//your function
foo();
},1000);

Try this out:
function checkStatus() {
$.ajax({
type: 'GET',
url: "http://xmychannelx.api.channel.livestream.com/2.0/livestatus.json?callback=?",
dataType: 'jsonp',
success: function (jsonp) {
// parse the JSON data on success
var channel = eval(jsonp);
liveChannel = channel.channel.isLive;
if (liveChannel == true) {
document.getElementById('mydiv').innerHTML = '<p style="color: #00FF00">Online!</p>';
} else{
document.getElementById('mydiv').innerHTML = '<p style="color: #C0C0C0">Offline!</p>';
}
}
});
}
$(function() {
setInterval(checkStatus, 5000);
});
This calls the function checkStatus every 5000 milliseconds (5 seconds).

How Can I Do to my textbox autocomplete, works

I'm trying to do an autocomplete to my textbox, but it doesn't work. Follow my code.
$(function () {
var credenciada = '<%= credenciadaId %>';
xml_NomeCompleto = "";
var Nomes = "";
var retorno = '';
var count = 0;
var t = '';
$.ajax({
url: "../Xml/AcessoExterno.aspx?Credenciada=" + credenciada,
type: "get",
dataType: 'xml',
async: false,
success: function (data) {
$(data).find("REGISTRO").each(function () {
t = $(this).find("NOMECOMPLETOUSUARIO").text();
Nomes += ["\"" + t + "\","];
});
}
});
$("#ctl00_contentConteudo_txtNome").autocomplete({ source: Nomes });
});
The variable 't' receives all the names of my users, normally, but the autocomplete don't work.

Wait for ajax response to complete and then initialize the autocomplete because before you initialize the plugin data is not available. Also the way you are creating Nomes(source) is wrong. Declare it as an array and use push method to populate it.
Try this
var Nomes = [];
$.ajax({
url: "../Xml/AcessoExterno.aspx?Credenciada=" + credenciada,
type: "get",
dataType: 'xml',
async: false,
success: function (data) {
$(data).find("REGISTRO").each(function () {
Nomes.push($(this).find("NOMECOMPLETOUSUARIO").text());
});
$("#ctl00_contentConteudo_txtNome").autocomplete({ source: Nomes });
}
});

jQuery AJAX works on mobile safari, but not a UIWebView?

I have a basic jQuery ajax function to log the user in via a UIWebView. However, for some reason it returns blank when it's in a UIWebView. It works fine in mobile safari, and chrome and firefox on my computer.
Here's my code:
$("#login_button").live('click',function() {
var serializeme = $("#login_form").serialize();
alert(serializeme);
$.ajax({
type: "POST",
url: "http://domain/location/process_login.php",
data: serializeme,
success: function(theRetrievedData) {
var thePlace = theRetrievedData.indexOf("?!?success?!?");
if (thePlace != -1) {
var theArray = theRetrievedData.split("?!?success?!?");
var theUrl = theArray[1];
$('#content').fadeOut(500);
setTimeout( function() {window.location = theUrl;}, 500 );
} else {
alert(theRetrievedData);
alert("no bueno");
}
}
});
});
The theRetrievedData just returns blank on the alert.
Please help!
PS: The app is called "Dudles" in the app store (it's free) if you want to try to login. You will get a blank message from the alert.

Can you post your PHP code as well?
I refactored the code you wrote into how I would write it just to see if I could spot any bugs, and nothing seemed glaringly incorrect. Here is what I have so far:
$(document.body).on('click', '#login_button', function () {
$.ajax({
type: "POST",
url: "http://domain/location/process_login.php",
data: $(this).closest('form').serialize(),
success: function (response) {
var delimiter = "?!?success?!?";
var isSuccessful = response.indexOf(delimiter) !== -1;
if (!isSuccessful) {
// handle error
return;
}
$('#content').fadeOut(500, function () {
location = response.split(delimiter)[1];
});
}
});
});

try to send ajax request with async:true, like this:
$("#login_button").live('click',function() {
var serializeme = $("#login_form").serialize();
alert(serializeme);
$.ajax({
type: "POST",
async:true,
url: "http://domain/location/process_login.php",
data: serializeme,
success: function(theRetrievedData) {
var thePlace = theRetrievedData.indexOf("?!?success?!?");
if (thePlace != -1) {
var theArray = theRetrievedData.split("?!?success?!?");
var theUrl = theArray[1];
$('#content').fadeOut(500);
setTimeout( function() {window.location = theUrl;}, 500 );
} else {
alert(theRetrievedData);
alert("no bueno");
}
}
});
});