Determine which element is first and do this - javascript

I need to set focus on the first form element or class of ".focus"; whichever is visible or first.
This does not seem to sort through each to determine which comes first?
http://jsfiddle.net/infatti/tdvHJ/1/
$('.focus:visible:first, body:not(:has(.focus:visible)) input:visible:first, body:not(:has(.focus:visible)) textarea:visible:first').focus();

This will locate all visible input elements, textarea elements and .focus elements:
$('input:visible, .focus:visible, textarea:visible')
It will also have them ordered according to their order in the DOM, so the first of those elements in the document will be the first in the jQuery object. To access the first:
$('input:visible, .focus:visible, textarea:visible').eq(0);
and to focus on it:
$('input:visible, .focus:visible, textarea:visible').eq(0).focus();
Note that, as I just found out, jQuery considers elements to be 'visible' if they take up space in the document. So elements with visibility:hidden or opacity:0 will still be considered visible:
http://api.jquery.com/visible-selector/

Like this ?
$('.focus:visible:first, body:not(:has(.focus:visible)) input:visible:first, body:not(:has(.focus:visible)) textarea:visible:first').eq(0).focus();
Fiddle :
http://jsfiddle.net/infatti/tdvHJ/1/
Eq(0) select the first element... ;)

Try:
$('.focus:visible:first').filter(":input").focus();
jsFiddle example

im not sure what you are trying to achieve as there isnt any elements with the class focus. Simply add the class focus to your input element and then us
$('.focus').focus();

Related

Select second element by custom data/attirbute

OK. I'm trying to get elements in javascript by CSS selector. To get one by custom element I know is like 'element[custom-name="Literal name"]'.
OK. This works. But now I need to get the second one. I mean I have some elements with the exact custom-name, and for everyone I need to apply a diferent rule (tehere are only 5).
How can I select the other ones? Is posibble select them by CSS?
PS: They are located in random positions, so maybe the first one is the 5 element one time and if I refresh the page it can be the 10 element inside the container.
PS2: No, It's not possible to change the HTML in my case :( . The only code I'm alowed to change is CSS and javascript.
Thanks for reading me! :D
Assuming you can't select specific ones by another, non-order-dependent factor, you can use the pseudo-selector :nth-child. In your case, the complete CSS selector would be element[custom-name="Literal name"]:nth-child(2) - substitute the 2 for any other number as you see fit. Generally it's not the best idea to select only by position in the document, as position may change more often than attributes - but in any case, there's a pure CSS solution!
Note that this only works if the elements you're working with are the only children of a common parent element - if you're looking for the second element that matches that query in general across the entire document, there is no way to do that with a CSS selector. Instead, you can make sure to add a unique class or other differentiating attribute to each element, or simply use querySelectorAll - in that case, you could get the second element using this little snippet: document.querySelectorAll('element[custom-name="Literal name"]')[1].

How do I remove non-visible elements from an entire document?

I want to use Javascript and JQuery to make a copy of the web page's entire html and remove all elements that are not visible to the user. This is what I've tried so far:
$('html').not(':visible').remove()
However, it does not seem to work. Does anyone know how I can accomplish this?
Right now you are only targeting the <html> element with your selector. You need to iterate through all the elements and check their visibility like this:
$('*').each(function(){
if($(this).not(':visible')){
$(this).remove();
}
});
Even more concise would be to just target hidden elements and remove them as such:
$('*:hidden').remove();
The jQuery API reference states that elements are considered visible if they take up space in the document. So elements that have a height and width greater than 0 are considered visible. This means we should instead look at the computed CSS if you are having issues with the above code removing things that are visible.
$('*').each(function(){
if($(this).css('visibility') == 'hidden' || $(this).css('display') == 'none'){
$(this).remove()
}
});
you are removing html elements which are not visible. you should remove its children.
try this
$('html').children().not(':visible').remove()
EDIT:
as Barmar said this only removes immediate children of html. use other answers to remove all elements.
This should do it:
$("body :hidden").remove();

How to use common js function for two divs containig elements of identical ids?

I have common jQuery function and two div tags. Both div tags have different names but both containing elements of identical ids now i want to use this common Jquery function for them both?
I have implemented common function but it's not working for both.
Here's link to my jsfiddle -jsfiddle.net/xS7zF/1/
In my jsfiddle there are two div tags namely example1 and example2 and both tags have elements of identical ids. Function is working fine for first div but not for second.
please help me to sort out this.
Yeah, under the hood, jQuery selection on an ID will use the Document.GetElementById() function implemented by the browser, which is really fast, but (i guess depending on the browser) will stop after it finds the first element, since ID's should be unique and no further searching is needed after the first one is found.
For instance, rename the divs with id="eb" to class="eb" and you can still target specific elements using $("#example1 .eb") and $("#example2 .eb")
UPDATE:
Using your new Fiddle I created this: http://jsfiddle.net/xS7zF/5/
I cleaned up a lot of code and hopefully you can see what I have done. I changed all elements that appear twice from id to class. Now, when you attach an event to an element using $(".classname").click(), it attaches to all the elements. In the handler function where you set HTML and do your show()/hide(), you don't target a specific element using it's ID, but you find it relative to the element that does the event. You can do this using parent(), parentsUntil(), next(), find(), etc. Check jQuery docs for all possibilities. So for instance, the change-handler attaches to all inputs with name=Assets. But instead of doing $("#b1").show(), I go to the parent of the specific input that fires using $(this).parent(). Then I find the element with a class=".b1", which it will only find the one that is next to this specific input and I set the HTML to just that element.
Since there is another input, the same actions happen when THAT input changes, but instead it finds IT's parent, and finds the element with class=".b1" that is next to IT. So both divs with input are contained since they act on elements relative to itself and not across the document.
For extra fun and to show you how flexible this way of programming is, here is a fiddle with the Javascript-code unchanged, but with the exact same question-div copied 8 times. No matter how many times you repeat this, the same code will act on as many divs as you create since everything works relative. http://jsfiddle.net/xS7zF/7/
Hopefully this helps, the rest is up to you!
ID's must be unique, you should not repeat them. You could replace id with class and in the jQuery function do (".ub").each() or manually referencing the object using eq(x). e.g. (".ub").eq(1).
You shouldn't assign same id's to different elements.
You CAN but you SHOULDN'T. Instead of giving the same id, use class
IDs must be unique, try fix this, change to classes.
You can try something like this:
$("div div:first-child")
instead of
$("#eb")
But depends of the rest of your page code. So, change to classes first and use
$(".eb")
when jQuery / javascript find the first ID it would ignore the rest, please read more about it
http://www.w3schools.com/tags/att_global_id.asp

Will jQuery select hidden elements

If I call .hide() on an element, will/can jQuery select it in a normal dom selector.
If jQuery does normally select hidden elements, what is the proper way to select only visible elements. Can I use a css selector, or is there a more valid way of doing this?
Yes. The hide function only stores the current value of the display css property of your element, then set it to none. So the dom selectors will not be affected by it unless they try to match elements with a particular display css value.
Check it here.
Have a look at the jQuery hide function documentation.
Yes it will count hidden elements.
Yes, it just adds a display:none style to the element... .remove() on the other hand will not show up in counts. But that completely gets rid of it, and unless you store the value somewhere it is not retrievable.
What I'm assuming you want to do is to count the visible items. I would instead do the following:
$('.element').addClass('hide');
var count_of_visible_items = $('.element:not(".hide")').length;
console.log(count_of_visible_items);

Help me with my selector, the ID is dynamically changing every page load

I want to scan a website using jQuery, but the ID is constantly changing, but there's a permanent pattern for the ID that I'm searching for:
app7019261521_the_coinb4678bc2
app7019261521_the_coind42fgr23
app7019261521_the_coing0992gvb
app7019261521_the_coin12e5d0aa
The IDs always starts with app7019261521_the_coin
But my problem is I don't know how to put that in jQuery selector.
$("#app7019261521_the_coin")
Doesn't seem to work
So how can I make this work?
$("[id^=app7019261521_the_coin]")
Should work - but its MUCH slower selector than knowing the real ID - or assigning a class. This selector will scan every element on the page one at a time, there is no good way for this selector to be optimizied. 9 times out of 10 though you could build a better selector: Is this #app7019... element the direct child of another element that is easier to determine? like a id='container'?
$("#conainter > [id^=app7019261521_the_coin]"); for instance
From the jQuery Selector Documentation
[attribute^=value] Returns: Array<Element(s)>
Matches elements that have the specified attribute and it starts
with a certain value.
can you set a class and just call it by a class name?
you may also be able to try
$("div[id^=app7019261521_the_coin]")
This will find all div's that start with app7019261521_the_coin
Replace div with whatever element type you are searching for.
$j('div[id^=app7019261521_the_coin]')
Remember this is not very optimal, as it causes the script to check the id attribute of every matched element.
You might want to see how you can add a class to the element or at least find the parent element first and traverse from there.

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