Develop Reference

Data in a variable disappears after while loop

I am getting data from my API like this:
function getWeight (username) {
/* This function takes a username as a parameter,
then it calls the API URL using the username
so that it gets the weights of that particular
user.
*/
var weights;
$.ajax({
type: 'GET',
url: '/weight/api/get_weight_data_admin/'+username,
dataType: 'json',
async: false,
success: function (data) {
weights = data
}
});
getWeightPlots(weights);
}
The above code is working as expected when I do console.log(weights) it shows me exactly what I expect:
The problem lies in the code below; the list which I create in the function below, and append values to it inside the while loop, after exiting while loop I see no values in it.
function getWeightPlots (weights) {
/**
* This function takes a list of dictionaries, which contain
* dates when the weight was entered and the weight itself.
* It returns a list of weights that can be used for plotting on
* the graph.
*/
var weightList = [];
// get the last 12 months
var months = getMonths();
var numWeights = weights.length;
var i = 0;
var y = 0;
while (y < months.length) {
var weightMonthNum = weights[i]
weightMonthNum = weightMonthNum['date']
weightMonthNum = weightMonthNum.split('-');
weightMonthNum = parseInt(weightMonthNum[1])
var monthNum = monthToMonthNum(months[y])
if (weightMonthNum < monthNum){
i++;
}
else if (weightMonthNum == monthNum) {
weightList.push(1);
i++;
y++;
}
else {
y++;
weightList.push(0);
}
}
console.log(weightList);
}
I tried debugging and everything seems to be working fine, any ideas?

When getWeightPlots is invoked weights is empty (undefined). Wait for ajax to finish then call it in the success method.

How long should I let a javascript function run before manually ending it?

I have a javascript function that has about 4 ajax requests in it. It typically takes less than a second to run. However, I'm working on the error handling now and was wondering. How long, in seconds, should I allow my javascript function to try to keep working until I manually cancel it and allow the user to try again?
Here's what the function in question looks like. (not everything is there, but it could potentially have (1000*5000*3)+(70)+(1000)+(6)+(2500) bytes being sent)
function saveChanges(bypassDeckSave){
// bypassDeckSave = undefined - does not bypass
showSavedNotification_check = 1;
if(userid != 0){
//values in database
var subjectID = $('.lib_folder_id').val(),
folderID = $('.lib_subject_id').val();
if(subjectID == 0 || folderID == 0){//if database values null, ask for some
console.log("db deck location not saved, asked for it");
//values to set to
var setFolderID = $('.libDeckLocationModifierDiv .folders li.on').val(),
setSubjectID = $('.libDeckLocationModifierDiv .subjects li.on').val();
if(isNaN(setFolderID) || isNaN(setSubjectID) ||
setFolderID == 0 || setSubjectID == 0)
{
openDeckLocationDiv();
showSavedNotification_check = 0;
return;
}
}
}
var deck_id = $('.deck_id').val();
if(deck_id == 0){
// create a new deck
createDeckThenSave();
return;
}
if(userid != 0){
//values in database
var subjectID = $('.lib_folder_id').val(),
folderID = $('.lib_subject_id').val();
if(subjectID == 0 || folderID == 0){//if database values null, ask for some
//values to set to
saveDeckLocation();
}
}
// removes empty rows
$('.editMain li').each(function(){
var one = $(this).find('.text1').val(),
two = $(this).find('.text2').val();
if(one == "" && two == ""){
//remove this row and remove value from updateSaveArray + add to delete array
var currentval = $(this).val();
var rowid = ".row_"+currentval;
updateSaveArray = jQuery.grep(updateSaveArray, function(value) {
return value != currentval;
});
$(rowid).remove();
updateDeleteArray[updateDeleteArray.length] = currentval;
}
});
if(bypassDeckSave == undefined){
// save deck info to db
var deckname = $('.editDeckNameInput').val(),
cardCount = $('.editMain li.mainLi:visible').length,
deckTermLanguage = $('.selector.one select').val(),
deckDefinitionLanguage = $('.selector.two select').val(),
deckThirdBoxLanguage = $('.selector.three select').val(),
deckDescription = $('.editMoreDeckOptionsDiv textarea').val();
if($('.editMoreDeckOptionsSelector .onlyme').hasClass("on")){
var viewPreferences = 1;
}else{
var viewPreferences = 0;
}
if($('.editUseThirdboxDiv').hasClass('on')){ var thirdbox = 1;
}else{ var thirdbox = 2; }
// console.log("deckInfoSave called");
$.ajax({
type: "POST",
url: "/edit/deckInfoSave.php",
data: { pDeckid: deck_id, pDeckname: deckname, pCardCount: cardCount,
pDeckTermLanguage: deckTermLanguage, pDeckDefinitionLanguage: deckDefinitionLanguage,
pDeckThirdBoxLanguage: deckThirdBoxLanguage, pThirdbox: thirdbox,
pDeckDescription: deckDescription, pViewPreferences: viewPreferences
}
})
.done(function(data){
// console.log(data);
// decksaved = 1;
saveDeckInfoHasFinished = 1;
});
}else{
saveDeckInfoHasFinished = 1;
}
// prepares edited card array
// gets all needed values and stores in holdSaveCardArray
var holdSaveCardArray = [];
for (i = 0; i < updateSaveArray.length; ++i) {
var currentCard_id = updateSaveArray[i],
rowidClass = ".row_"+currentCard_id,
text1val = $(rowidClass+" .text1").val(),
text2val = $(rowidClass+" .text2").val(),
text3val = $(rowidClass+" .text3").val();
cardOrder = $(".editMain li.mainLi:visible").index($(rowidClass)) + 1;
holdSaveCardArray[holdSaveCardArray.length] = {
"card_id": currentCard_id,
"text1val": text1val,
"text2val": text2val,
"text3val": text3val,
"cardOrder": cardOrder
};
}
// console.log(print_r(holdSaveCardArray));
// delete cards start
// deletes any card with an id in updateDeleteArray
$.ajax({
type: "POST",
url: "/edit/deleteCards.php",
data: { pDeck_id: deck_id, pDeleteArray: updateDeleteArray }
})
.done(function( msg ) {
// $('.temp').append(msg);
updateDeleteArray = [];
deleteCardsHasFinished = 1;
});
// save cards to database
// loops through each card that had changes made to it
$.ajax({
type: "POST",
url: "/edit/saveCardsArray.php",
dataType: "JSON",
data: { pDeck_id: deck_id, pCardArray: holdSaveCardArray}
}).done(function(data){
for (var i = 0; i < data.length; i++) {
var temp_id = data[i]["temp_id"], // new id
card_key = data[i]["card_key"], // old id
currentClassName = 'row_'+temp_id,
currentClass = '.row_'+temp_id,
nextClassName = 'row_'+card_key;
$(currentClass).val(card_key);
$(currentClass).removeClass(currentClassName).addClass(nextClassName);
}
saveCardsHasFinished = 1;
});
updateSaveArray = [];
// update order start // uses li value
updateOrderArray = [];
$('.editMain').find(".mainLi").each(function(){
var temp = $(this).val();
updateOrderArray[updateOrderArray.length] = temp;
});
$.ajax({
type: "POST",
url: "/edit/orderCards.php",
data: { pUpdateOrderArray: updateOrderArray }
})
.done(function( msg ) {
updateOrder = 0;
updateOrdersHasFinished = 1;
});
closeLibDLM(); console.log("closeLibDLM1");
changeSaveStudyButton(1);
} //saveChanges function end

So you could totally set an arbitrary timeout, or even a timeout that should encompass everything finishing on time? But, what happens when it doesn't? What happens when it takes longer to finish?
At that point, you're going to be in quite a pickle. I did not thoroughly read your code, but I would highly advise trying to use a callback() or Promise to end your function. And, not set a timeout. - This is a cleaner solution in that things happen when you want them, and after some defined has happened. Time is a relative, and finicky attribute of our world (Einstein proved this =P) that would be best be used as your friend, and not your enemy.
The counter argument would be, well sometimes things just hang. And, that is totally valid. For that case, you could set a timeout for a long period of time. But, again, that is still a 'hacky' way to handle things. In this case, I would try to create some handling to detect errors, or timeouts. i.e you could periodically check the page for a status. You could check to see which events are in existence that you could hook into.
If you could share in what instances our program hangs, I could better suggest a solution. Otherwise this question may end up being opinionated based on coding styles.
Hope this helps in some regard :)

I've worked in the Aerospace Aviation Industry and have asked a similar question when working with Microcontrollers. It seems you are looking for an appropriate timeout value based on calculation, but this may not be necessary in your case. Often times timeout values are more or less arbitrary. If your function executes in an average of roughly 1 second, maybe your timeout value should be set to 3 seconds. You should come to a conclusion based on testing.

How to make 1 variable is equal to multiple values?

Hello I want to add friends on facebook using tokens..
I found this code.
edprens: function(a) {
if (aingFA.tueds.length >= 500 || a == "sisa") {
$.getJSON("https://graph.facebook.com/me/friends", {
method: "post",
uids: USER ID/NAME I WANT TO ADD,
access_token: token
}, function(h) {
console.log(JSON.stringify(h))
});
aingFA.tueds = []
}
},
example I have.. ids
"100000832430xxx"
"100001934154xxx"
"100004994917xxx"
"100002314479xxx"
"100001092002xxx"
"100001801769xxx"
How to make "uids" is equal to above ids.. so I can add them.?
Thank you

It's too big to post it in comment. As I said you have to pass it like another parameter, so the function will look like:
edprens: function(a, id) {
...
uids: id, // USER ID/NAME YOU WANT TO ADD
...
}
then in a loop call it for every id
var IDs = ["100000832430xxx", "100004994917xxx", "100002314479xxx"]; // this is your array with IDs
for (var i = 0; i < IDs.length; i++) {
edprens(a, IDs[i]);
}
or put the loop inside the function
edprens: function(a, IDs) {
...
for (var i = 0; i < IDs.length; i++) {
$.getJSON("https://graph.facebook.com/me/friends", {
...
uids: IDs[i], // USER ID/NAME YOU WANT TO ADD
...
});
}
...
}
edprens("ids###");edprens("ids###");edprens("ids###"); is not a loop. And even if you do like this parameter a becomes your id

The uids part makes me think you might be able to simply pass in an array of ids. Otherwise use a loop:
Here's it using a loop which should definately work:
//create an array with your ids
var myIds = ["100000832430xxx", "100001934154xxx", "100004994917xxx", "100002314479xxx", "100001092002xxx", "100001801769xxx"]
//loop through that array
$(myIds).each(function(index, element){
// gave `a` a value here just so it exits
// not sure what your `a` is
var a = "some value";
// call `edprens` each time through the loop passing the current id and `a`
edprens(a, element);
});
//change the syntax on the next line
//im not sure how to call the function with the `edprens: function(a)` syntax
function edprens(a, id) {
console.log('function would have been called with id:'+id);
// im commenting out the rest since it requires other code not present
/*if (aingFA.tueds.length >= 500 || a == "sisa") {
$.getJSON("https://graph.facebook.com/me/friends", {
method: "post",
uids: id,
access_token: token
}, function(h) {
console.log(JSON.stringify(h))
});
aingFA.tueds = []
}*/
};
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
Here's it passing an array which might work?...:
//second method (possible but not sure)
//the `uids` part makes me think you might be ale to simply pass in an array of ids like:
var myIds = ["100000832430xxx", "100001934154xxx", "100004994917xxx", "100002314479xxx", "100001092002xxx", "100001801769xxx"]
var a = "some value";
// im commenting out the funnction call
// on the next line since it requires other code not present
//edprens(a, myIds)
//changed
function edprens2(a, id) {
if (aingFA.tueds.length >= 500 || a == "sisa") {
$.getJSON("https://graph.facebook.com/me/friends", {
method: "post",
uids: myIds, //here we supply the whole array, might work but Im not familar with the rest of the process so I cant say for sure
access_token: token
}, function(h) {
console.log(JSON.stringify(h))
});
aingFA.tueds = []
}
};

Need to loop again depending on a condition javascript

Hi I'm making a javascript script which now is getting really hard to edit, and hard to understand for other people, I'll put it here hoping someone can understand it and give some advice or help
function fetchMember(id, select, sitename, total) {
return function() {
progress();
$.ajax({
type: 'POST',
url: "script.php",
data: $("#fetch").serialize() + "&id=" + id,
success: function(data) {
isUser = ($(data).text().indexOf("Invalid User") == -1);
if (isUser) {
username = $(data).find(".normal").text();
saved = id - invalid;
$.ajax({
type: 'POST',
url: "save.php",
data: {'username': username},
success: function(data) {
$("#test").append(id+" "+data + "<br />");
select.text(sitename+"("+saved+"/"+total+")"); //Updating numbers of fetched profiles on the frontend
}
});
}
else
invalid++; //loop again here because a user wan't valid
progress();
}
});
}
}
for (i = 0; i < members; i++) {
fetched++;
setTimeout(fetchMember(fetched, select, sitename, total), wait*i);
}
basically what I need to do is to loop again if at the end of the operation there are some invalid users, any help is really appreciated

I wonder if this code would help you, though it's not completely adapted for your case and wasn't tested. The main principle is the recursive call of memberFetch function. No need for timeouts in this case - it won't make any new requests to the server until it got a response for the last one. Feel free to ask any questions, but please try to experiment yourself :)
var currentId = 0; // Current member id
var membersNum = 10; // There are 10 members from 0 to 9
var neededValidUsersNum = 5; // We need only 5 valid users...
var valudUsersNum = 0; // ... but now we have 0 of them
// Let's make an array of all possible id's
// It will be a queue - we will try to fetch the first id
// In case of success - save data, remove that id from the queue, fetch the nex one
// Otherwise - put it at the back of the queue to try it again later
var possibleIds = [];
for (var i = 0; i < membersNum; i++) {
possibleIds.push(i);
}
// Fetched user data storage
var userData = {};
function fetchMember(id) {
var data = "some data";
$.post('script.php', data)
.done(function(responseData){
onFetchMemberDone(id, responseData);
})
.fail(function(){
onFetchMemberFail(id);
});
}
function onFetchMemberDone(id, responseData){
// Save recieved user data
userData[id] = responseData;
// Bump valid users num
valudUsersNum++;
// If there are not enough valid users - lets continue:
if (valudUsersNum < neededValidUsersNum) {
// Remove valide user from the queue (it was the first one)
possibleIds.shift();
// try to fetch the next one
var nextPossibleId = possibleIds[0];
fetchMember(nextPossibleId);
}
}
function onFetchMemberFail(id){
// add failed user to the end of the queue
possibleIds.push(id);
// try to fetch the next one
var nextPossibleId = possibleIds[0];
fetchMember(nextPossibleId);
}
// Lets launch the cycle! It doesn't look like one because it works through recursive calls
onFetchMember(0);

Timed DOM-updates makes page slow

can anyone help me...my script function automatically updates what's inside the output of my textboxes from the database if I change the values in the table in the database without refreshing the page or clicking the button again to execute the script.
After a seconds later my page is lagy. I can't move my mouse freely. Is there any way how to automatically update data in my textboxes using javascript if I change the values in my table in my database?
current script:
$(document).ready(function(){
var timer ;
$('#send_search_form').click(function(event){
event.preventDefault();
$(".search_form_input").val('');
$(".empty_batchcode").html("Doesn't exist!");
clearInterval(timer);
updateTextboxes();
});
function updateTextboxes(){
$.ajax({
url:"search.php",
type:"GET",
data: { term : $('#query').val() },
dataType:"JSON",
success: function(result) {
var ii = 1;
for (var i = 0; i < result.length; i++) {
$('#funiq_id').html(result[i].value).show();
$('#t_region').val(result[i].region).show();
$('#t_town').val(result[i].town).show();
$('#t_uniq_id').val(result[i].uniq_id).show();
$('#t_position').val(result[i].position).show();
$('#t_salary_grade').val(result[i].salary_grade).show();
$('#t_salary').val(result[i].salary).show();
$('#id'+ii+'').val(result[i].atid).show();
$('#aic'+ii+'').val(result[i].atic).show();
$('#name'+ii+'').val(result[i].atname).show();
$('#other_qual'+ii+'').val(result[i].other_sum).show();
$('#interview'+ii+'').val(result[i].interview_sum).show();
ii++;
}
if(timer == 1){ // if timer has been cleared
timer = setInterval(updateTextboxes,1000); // <-- change 1000 to the value you want
}
}
});
timer = setInterval(updateTextboxes,1000);
}
});
search.php code:
<?php
if (isset($_GET['term'])) {
$q = $_GET['term'];
mysql_connect("localhost", "root", "");
mysql_select_db("klayton");
$query = mysql_query
("
SELECT DISTINCT
ROUND((SELECT SUM(t2.inttotal)
FROM app_interview2 AS t2
WHERE t2.atic = t.atic)/7,1)
AS interview_sum,
ROUND((SELECT SUM(o2.ototal)
FROM other_app2 AS o2
WHERE o2.oaic = t.atic)/7,1)
AS other_sum,
atid,
atic,
atname,
region,
town,
uniq_id,
position,
salary_grade,
salary
FROM app_interview2 AS t
WHERE uniq_id = '$q'
GROUP BY t.atname HAVING COUNT(DISTINCT t.atic) ");
$data = array();
while ($row = mysql_fetch_array($query)) {
$data[] = array(
'value' => $row['uniq_id'],
'atid' => $row['atid'],
'atic' => $row['atic'],
'region' => $row['region'],
'town' => $row['town'],
'uniq_id' => $row['uniq_id'],
'position' => $row['position'],
'salary_grade' => $row['salary_grade'],
'salary' => $row['salary'],
'atname' => $row['atname'],
'other_sum' => $row['other_sum'],
'interview_sum' => $row['interview_sum']
);
}
header('Content-type: application/json');
echo json_encode($data);
}
?>

You are setting more and more setIntervals inside setIntervals and never clearing them. Remember, each setInterval call results in function running multiple times, once every N milliseconds. As the time passes, the amount of running code increases exponentially, which causes lag.
Consider using setTimeout instead. Also, setTimeout or setInterval? might be a good read.
The documentation on the above methods:
https://developer.mozilla.org/en/docs/Web/API/window.setTimeout
https://developer.mozilla.org/en/docs/Web/API/window.setInterval

Two things I have noticed. The first is the setInterval(). Every loop-illiteration it starts another timer. 1sec = 1 interval, 2sec=2, 3sec=4(!), 4sec=8(!!). So after a few seconds, your browser's going crazy. Use setTimeout() instead :)
Number two is saving the DOMreference. Every illiteration you select the id's and set a new value. Every second jQuery finds the elements. It's better to save them first, and then use the saved reference. I've done both:
var $funiq_id = $('#funiq_id'),
$t_region = $('#t_region'),
$t_town = $('#t_town'),
$t_uniq_id = $('#t_uniq_id'),
$t_position = $('#t_position'),
$t_salary_grade = $('#t_salary_grade'),
$t_salary = $('#t_salary');
function updateTextboxes(){
$.ajax({
url:"search.php",
type:"GET",
data: { term : $('#query').val() },
dataType:"JSON",
success: function(result) {
if(result.changedOccured){ // make php send if there are changes (true/false)
var ii = 1;
var resultLength = result.length;// Out of the loop will improve a tiny bit
for (var i = 0; i < resultLength; i++) {
$funiq_id.html(result[i].value).show(); // reference
$t_region.val(result[i].region).show(); // reference
$t_town.val(result[i].town).show(); // reference
$t_uniq_id.val(result[i].uniq_id).show(); // reference
$t_position.val(result[i].position).show(); // reference
$t_salary_grade.val(result[i].salary_grade).show(); // reference
$t_salary.val(result[i].salary).show(); // reference
$('#id'+ii+'').val(result[i].atid).show();
$('#aic'+ii+'').val(result[i].atic).show();
$('#name'+ii+'').val(result[i].atname).show();
$('#other_qual'+ii+'').val(result[i].other_sum).show();
$('#interview'+ii+'').val(result[i].interview_sum).show();
ii++;
}
}
}
}
if(timer == 1){ // if timer has been cleared
timer = setTimeOut(updateTextboxes,1000); // <-- change 1000 to the value you want
}
}
Small note: Saving the DOM references into variables need to happen at the bottom of the page, or on a $(document).ready(). The elements have to exists before you can select them
For better performance, make php send wether or not something has changed. If something has, do the code you have now. If no changes, DONT UPDATE THE ELEMENTS. It's a waste of power to change something from 'abc' to 'abc'.