This might be a very basic question but I'm trying to understand this behavior
This is my javascript code. I want to know why second call to foo does not work. Here is the JSFiddle link
$.fn.foo = function(somestring){
var $this = this;
$this.html(somestring);
}
$(function(){
$('#container').foo("within function"); //this works
});
$('#container').foo("outside"); //this does not
The DOM is not fully loaded .. Thats the reason it won't work..
So when you encase your code inside the DOM Ready handler it waits for the document to be loaded and then runs the code inside.
This makes sure the element is available before any code is run on it..
When the HTML document is parsed , it parses top down.
So if the script is included in the head section , then the scripts are loaded first and then the HTML structure.. When you try to the run the code , it obviously won't work cause the element was still not parsed..
So encasing that in the handler will make sure the element is available before calling the methods on them..
This is because $('#container').foo("outside"); is evaluated before the body is processed. $('#container') will return with a length of 0. This is demonstrated below.
$.fn.foo = function(somestring){
var $this = this;
$this.html(somestring);
}
$(function(){
$('#container').foo("within function");
});
var element = $('#container');
console.log(element.length); //prints 0
element.foo("outside");
If the script is at the beginning of the page the rest of the HTML document has not been parsed yet, so the document looks empty to the script, so there is no #container yet.
$(function() { ... });
is (roughly) equivalent to
Wait till the whole HTML file is loaded and ready
Then execute function
so #container will be there and it will work. Another way to make it work would be to put the script below the rest of the page or at least below #container.
Related
In my <body> I have a component that inserts a script that is supposed to run only after all the page has completely loaded:
<script>
$('<script id="smallPlacarScriptdId">\
$(window).load(function() {\
$(".main.right").hide();\
$("#rightzero").show();\
$(".comp.smallPlacard.firstChild").click(function () {\
var clicked = $(this).parent().attr("id");\
$("main.right").hide();\
$("#right"+clicked+"").show();\
});\
})\
<\script>').appendTo("body")
</script>
That's not happening and this script (1) is correctly inserted into the DOM but (2) is not working (not hiding .main.right nor showing #rightzero).
I though that by using this approach I would guarantee that it would be the same as just put this script at the bottom of the <body> but it isn't. In fact if I put it (not dynamically like this) in my page it produces the desired result.
I tried setTimeout() to validate my theory but I'm getting an error in jQuery and I'm lost.
That might be the problem:
<\script>').appendTo("body")
Browser might think you are actually closing your script tag. Change it to
</' + 'script>').appendTo("body")
Check this plunker out: http://plnkr.co/edit/Oc6yrFMdPoW2WV257CBQ?p=preview
Just use this code
<script id="smallPlacarScriptdId">
$(window).load(function() {
$("main.right").hide();
$("#rightzero").show();
$(".comp.smallPlacard.firstChild").click(function () {
var clicked = $(this).parent().attr("id");
$("main.right").hide();
$("#right"+clicked+"").show();
});
})
</script>
Sorry I didn't read you question well enough.
Javascript will allow you to access undeclared variables, so use that to your advantage. Check if a variable is set, undefined is treated as a false so no need for initialization. As soon as you enter the code just set it to true so nothing else will execute.
Hopefully this solves the problem for you, but you really should look at from the server avoiding the javascript, it will bloat the page.
<script>
if (!myScriptHasLoaded)
{
myScriptHasLoaded = true;
$(window).load(function() {
$("main.right").hide();
$("#rightzero").show();
$(".comp.smallPlacard.firstChild").click(function () {
var clicked = $(this).parent().attr("id");
$("main.right").hide();
$("#right"+clicked+"").show();
});
});
}
</script>
// Some jQuery to load the HTML file
$(function(){
$("#myDiv").load("./someHTMLfile.html");
});
var div = document.getElementById("myDiv");
console.log(div.childNodes);
console.log(div.childNodes[0]); // Prints undefined
When this code runs, the list div.childNodes is empty, but when I check the variable in the Chrome console, the list is not empty. Chrome also tells me that "Object state below is captured on first expansion".
When I execute console.log(div.childNodes[0]) in the Chrome console, it returns the first element, as it should. I've also tried to make the script execute after the page is fully loaded with jQuery $(document).ready(), but it didn't solve anything.
Why is this and how do I fix it?
load runs asynchronously, plus you've wrapped it in the jQuery ready function. All this means that console.log(div.childNodes) is running well before someHTMLfile.html has been loaded and inserted.
What you need to do is use the callback function available in load to run any functionality that depends on the html:
$(function(){
$("#myDiv").load("./someHTMLfile.html", function() {
var div = document.getElementById("myDiv");
console.log(div.childNodes);
console.log(div.childNodes[0]);
});
});
I have a javascript function, "loadFramework()" that modifies an HTML document. Specifically, it repeatedly runs the jQuery command $("#element-id").load("document/name.html"), which injects the HTML in document/name.html directly into the element with #element-id.
Originally, I ran loadFramework() in a script in the document's header. However, since then I've realized that the function fails if the page has not loaded yet, since it relies on there being an element with #element-id.
I can't figure out how to get this function to run when it should. A simple solution seemed to be setting it to be the document.onload function:
document.onload = function() {
loadFramework();
}
But in this case it never seems to run at all.
How do I make sure a header function runs only after the document has loaded?
You should use window.onload if you are looking for a vanilla JS option
window.onload = function() {
loadFramework();
}
Jquery load takes additional argument "complete". You can run the javascript there. So the code would be:
$("#element-id").load("document/name.html", function(){
loadFramework();
});
You can also use $(document).ready(function{loadFramework()}) inside the html you are loading.
If you want to execute the loadFramework() method after "document/name.html" is loaded, I would suggest the following code.
$(function() {
$("#element-id").load("document/name.html", function(){
loadFramework();
});
});
I want to know why I can use .load to load a very specific bit of information to a page but then when I try to read back the loaded information I am just returned null
this is the jquery I am using to load this bit of information
$(function(){
$('#code').load('stuff.html #specificstuff');
});
And this is the code I am using to repeat what is in #code
var content = document.getElementById('#code');
document.write(content);
But when this is run, I am just getting back null
document.getElementById('#code');
should be
document.getElementById('code');
That being said... I have no clue why you are using document.write in the first place.
And you need to wait for the load to finish, so it would make more sense to do:
$('#code').load('stuff.html #specificstuff', function(){
var content = document.getElementById('code').html();
document.write(content);
});
$.load() is asyncronous, so your code:
var content = document.getElementById('#code');
document.write(content);
gets executed before the actual content is loaded.
Put it in a callback function like this:
$(function(){
$('#code').load('stuff.html #specificstuff', function(){
var content = document.getElementById('code');
document.write(content);
});
});
so it gets executed after the content has done loading.
That said, document.write(content); in this case is useless, as $('#code').load() replaces the content of the element with id="code" with the content of the element #specificstuff of the file stuff.html.
I wanted to load some fragments of external content inside a div, through a menu.
Found "load" and "live", found a tutorial used it = success!
Except, like what's explicit in the documentation, it doesn't load JavaScript.
The thing is, the destination page already loads, inside the header, that same JavaScript, 'cause Wordpress loads it in every page. In this particular page, I'm only using the plugin (nextgen gallery) through the jQuery AJAX call.
So, what I believe is my problem is that I somehow need to alert/reload the JavaScript, right?
And how can I do this?
<script type="text/javascript" charset="utf-8">
jQuery(document).ready(function(){
// ajax pagination
jQuery('#naveg a').live('click', function(){ // if not using wp-page-numbers, change this to correct ID
var link = jQuery(this).attr('href');
// #main is the ID of the outer div wrapping your posts
jQuery('#fora').html('<div class="loading"><h2>Loading...</h2></div>');
// #entries is the ID of the inner div wrapping your posts
jQuery('#fora').load(link+' #dentro')
return false;
});
}); // end ready function
</script>
PS: I've substituted "live" with "on" but didn't work either.
I'm not sure if I understand... your load() command is puling in some Javascript that you want executed? I'm not sure if you can do that. But if you just need to call some JS upon load() completion, you can pass it a function like so:
jQuery('#fora').load(link+' #dentro', function() {
console.log("load completed");
// JS code to be executed...
});
If you want to execute Javascript code included in the loaded page (the page you retrieve via .load()), than you have to use the url-parameter without the "suffixed selector expression". See jQuery documentation for (.load()):
Note: When calling .load() using a URL without a suffixed selector expression, the content is passed to .html() prior to scripts being
removed. This executes the script blocks before they are discarded. If
.load() is however called with a selector expression appended to the
URL, the scripts are stripped out prior to the DOM being updated,
which is why they are never executed. An example of both cases can be
seen below:
Here, any JavaScript loaded into #a as a part of the document will
successfully execute.
$('#a').load('article.html');
However in this case, script blocks in the document being loaded into
#b are stripped out prior to being executed:
$('#b').load('article.html #target');
I think that's your problem (although I have no solution for you, sorry).
Proposal: Maybe you can load the whole page (including the Scripts) and remove (or hide) the parts you don't need?
Cheers.