Can't get value of <select> element in jQuery - javascript

I want to create a web app like google sheets in jQuery, but when I try to get a <select> value with $(select).val() I get `null.
I tried to put the code into $(button).click() and then it worked so I think the problem is that Javascript is executed before HTML, but I am not sure.
$(function() {
$.post("getTablesName.php", function(data) {
$("#tables_SCT").html(data);
});
var name = $("#tables_SCT").val();
$.get("getTable.php", { name: name }, function(data) {
$("#columns").html(data);
});
)};
I just want to get the $("#tables_SCT").val().

You will need to put the var name = $("#tables_SCT").val(); line inside the first AJAX callback. As it stands your code is trying to read content which doesn't yet exist in the DOM as the request which fills the option elements is asynchronous.
You will also need to make the second AJAX call from this point too, for the same reason. Try this:
$(function() {
$.post("getTablesName.php", function(data) {
$("#tables_SCT").html(data);
var name = $("#tables_SCT").val();
$.get("getTable.php", { name: name }, function(data) {
$("#columns").html(data);
});
});
)};

Related

'book' textfield does not trigger event in sencha

I have this code Ext.get('book').setValue('1');
Note: Loads the page and book value is set to 1. Not after page load
and book value change to 1.
It sets the book to value 1. But it does not trigger a change event. Is there a way to trigger the change event after page loads?
Edit:
In html script,
<script..>
$(document).ready(function () {
$("book").on("blur", function() {
//calls other function
}); // not called as blur is not invoked
});
</script>
<input id="book" type="book" value="" /><br />
In extjs,
var panel = Ext.create('Ext.grid.Panel', {
id: 'panel',
columns: [
var bookid = "new book";
Ext.Ajax.request({
params: { bookid: bookid},
function: function (response) {
Ext.get('book').setValue(bookid);
// after setValue, book will receive a change event(e.g .blur in html) and changes other functions
}
});
]
});
Your ajax request seems to be malformed, the function: function statement would be the place where you put normally success: function like in the following statement:
Ext.Ajax.request({
url: 'insert-your-http-endpoint-here',
params: {
bookid: bookid
},
success: function(response){
debugger; // -> setting this statement will show that you enter the success statement
Ext.get('book').setValue(bookid);
},
failure: function(response, opts) {
// something went wrong with your request
console.log('server-side failure with status code ' + response.status);
}
});
more info about how to use ExtJS or the specific function, you could find in the documentation (check if you have the correct version, ofcourse) which can be found here
From the above code, you don't need the debugger statement, but it could help if you want to check if you actually get into this code block or not, and what happens when you try to set the value.
Also, don't forget to check your console output when something is not working, maybe there was a problem that would be clearly indicated in the console log

jquery.get function url parameter

in the jquery.get() function, the first parameter is URL, is that the url to the content I want to retrieve or to the Controller/action method.
The problem is I'm building an asp.net-mvc application and I'm not sure what to pass as this parameter. Right now I'm passing my partialview.cshtml but nothing is being returned, not sure if I'm doing this right or wrong.
Here's what I got
<div id="editor_box"></div>
<button id="add_button">add</button>
<script>
var inputHtml = null;
var appendInput = function () {
$("#add_button").click(function() {
if (!inputHtml) {
$.get('AddItem.cshtml', function (data) {
inputHtml = data;
$('#editor_box').append(inputHtml);
});
} else {
$('#editor_box').append(inputHtml);
}
})
};
</script>
also, what is the second parameter "function (data)" is this the action method?
You need to remove var appendInput = function () { from the script. You are defining a function but never calling it. Just use the following (update you action and controller) names
<script>
var inputHtml = null;
$("#add_button").click(function() {
if (!inputHtml) {
$.get('#Url.Action("SomeAction", "SomeController")'', function (data) {
inputHtml = data;
$('#editor_box').append(inputHtml);
});
} else {
$('#editor_box').append(inputHtml);
}
});
</script>
Edit
Based on your script you appear to be requiring the content only once (you then cache it and add it again on subsequent clicks. Another alternative would be to render the contents initially inside a hidden <div> element, then in the script clone the contents of the <div> and append it to the DOM
<div id="add style="display:none">#Html.Partial("AddItem")</div>
$("#add_button").click(function() {
$('#editor_box').append($('add').clone());
});
The first argument to $.get is the URL which will respond with the expected data. jQuery/JavaScript don't care what kind of server side architecture you have or the scripting language. Whether the URL looks like a file AddItem.cshtml or a friendly route like /User/Sandeep, it doesn't matter as far as the client side is concerned.
In the case of ASP.NET, your URL endpoint can be generated like so:
$.get('#Url.Action("SomeAction", "SomeController")', function (data) {

Modifying html of dom element that was created after page loaded

I have two separate AJAX calls. One that gets a list of items from a txt file and creates an HTML table out of them and one that talks to a database to find how much each item costs and then lists this in the corresponding table cell for each item (I know this may sound like a strange approach, but it's a good option in our case...).
The issue is that the price is not getting written to the table since the table is created (or to be precise, the rows of the table are created) after the page loads. I'm not sure how to fix this.
$(document).ready(function() {
makeItemTable();
listPrices();
...
});
function makeItemTable() {
$.ajax({
url: 'products.php',
type: 'GET'
})
.done(function(response) {
$('.price-table > tbody').html(response);
})
}
function listPrices() {
.ajax({
url: 'prices.php',
type: 'GET'
})
.done(function(response) {
priceData = $.parseJSON(response);
$('.price-table tr').each(function() {
var item = $(this).find('td:nth-child(1)').text();
if (priceData[item]) {
var price = priceData[item];
$(this).find('td:nth-child(2)').text(price);
}
})
}
You can try
Using setTimeout to check request to 'products.php' execute callback done (inside callback for request to 'prices.php')
Another way
var jqxhr1 = $.ajax("products.php");
var jqxhr2 = $.ajax("prices.php");
$.when(jqxhr1, jqxhr2).done(function(jqxhr1, jqxhr2) {
// Handle both XHR objects
alert("all complete");
});
Call function listPrices() inside callback request to 'products.php'
Hope to help

Show loading animation when collapsible block is opening Jquery Mobile

I have a problem trying to show loading icon when collapsible block is opening. I have a collapsible block with a listview inside which is populated dynamically via ajax/php. They list might have up to 500 elements, so I would like to show loading animation while it is loading.
I have tried
$('div.century').live('expand', function(){
var idval = $(this).attr('id');
console.log('expanded'+idval);
$.mobile.showPageLoadingMsg ();
$.get("helpers/getByCentury.php", { id: idval},
function(data){
$("#"+idval+" ul.ulist").html(data);
$("#"+idval+" ul.ulist").listview('refresh');
});
$.mobile.hidePageLoadingMsg ();
});
I have also tried
$('div.century').live('expand', function(){
var idval = $(this).attr('id');
console.log('expanded'+idval);
$.mobile.pageLoading();
$.get("helpers/getByCentury.php", { id: idval},
function(data){
$("#"+idval+" ul.ulist").html(data);
$("#"+idval+" ul.ulist").listview('refresh');
});
$.mobile.pageLoading(true);
});
without any luck.
Can anyone tell me how to fix this?
Thanks in advance.
You want to call $.mobile.hidePageLoadingMsg() in the callback function for your ajax call:
$('div.century').live('expand', function(){
var idval = $(this).attr('id');
console.log('expanded'+idval);
$.mobile.showPageLoadingMsg ();
$.get("helpers/getByCentury.php", { id: idval},
function(data){
$("#"+idval+" ul.ulist").html(data);
$("#"+idval+" ul.ulist").listview('refresh');
$.mobile.hidePageLoadingMsg ();//NOTICE: this has been moved inside the callback function for your $.get() call
});
});
Also a couple pointers.
You are using the $("#"+idval+" ul.ulist") selector twice in a row, you can make that more efficient by chaining function calls together like so:
$("#"+idval+" ul.ulist").html(data).listview('refresh');
If other people view your webpage in a browser that does not have the console.log function they will get an error and your JS will stop running, it is normally a good idea to put calls to the console.log function inside a conditional that checks for the existance of that function:
if (typeof(console.log) == 'function') {
console.log('expanded'+idval);
}

Basic Javascript Global Scope Issue

I'm having issues with scope in Javascript. Take a look at this code, for example:
$(function() {
var items = "GLOBAL";
$('.add').click(function() {
$.post("main/get", { 'get' : 'all' },
function(data){
items = String(data.result);
items = items.split(' *** ');
alert(items);
}, "json");
alert(items);
return false;
});
$(".add").autocomplete({
source: items
});
});
I'm trying to get autocomplete working, and it almost is. The only problem is that I can't seem to change items outside of the inner-most function. The first alert gives me what I'm looking for, but the second just gives me "GLOBAL." The bottom autocomplete part has to be able to access it.
Any help is appreciated!
Thanks!
It is not just a scope issue. Since your request is very likely to happen asynchronously (unless configured otherwise) it won't work that way anyway. You have to initialize the autocomplete in the callback function which gets called once your AJAX request is complete:
$(function() {
$('.add').click(function() {
$.post("main/get", { 'get' : 'all' },
function(data){
var items = String(data.result);
items = items.split(' *** ');
$(".add").autocomplete({
source: items
});
}, "json");
});
});

Categories

Resources