Might be a strange setup, but I have a number of hyperlinks on the page with the same id (yeah, I know, but it was not my choice and I cannot change that at this time plus those hyperlinks are generated dynamically).
Example:
<div id="Links">
<div class="myItem">Some text</div>
<div class="myItem">More text</div>
<div class="myItem">Even more text</div>
</div>
Now I need to attach javascript to those links dynamically (the hyperlinks are also dynamically generated). The easiest way I see is by getting all hyperlinks on the page and then check the hyperlink id to ensure I only take care of those that have id of "myLink" (I have many other hyperlinks on the page).
I thought of using getElementById but that would only grab the first element with the specified id.
am attaching javascript to those links using the following:
window.onload = function() {
var anchors = document.getElementsByTagName('a');
for(var i = 0; i < anchors.length; i++) {
var anchor = anchors[i];
if (anchor.id='myLink')
{
if (anchor.getAttribute("LinkID") != null)
{
anchor.onclick = function() {
MyFunction(this.getAttribute("LinkID"), false);
return false;
}
}
}
}
}
The above function works fine, but it creates another issue - affects the styling of other hyperlinks on the page. So I was wondering if there is a way to accomplish the same thing but without affecting other elements on the page?
This is more modern and corrects your equality test:
window.onload = function() {
var anchors = document.getElementsByTagName('a');
for(var i = 0; i < anchors.length; i++) {
if (anchor[i].id==='myLink' && anchor[i].getAttribute("LinkID") !== null)
{
anchor[i].addEventListener("click", function() {
MyFunction(this.getAttribute("LinkID"), false);
}
}
}
}
Even with your original code, I don't see anything that would interfere with styling in the code. Can you elaborate as what styling changes you were getting?
You can use an attribute selector and document.querySelector([id=<id>]) pretty reliably depending on your browser support situation: http://codepen.io/anon/pen/YwLdKj
Then, of course, loop through that result and make subsequent changes or event bindings.
If not, you could use jQuery (referenced in above code pen).
You might also use JavaScript event delegation and listen for all click events, check if the user is clicking a link with the correct id.
If a combination of tag == 'a', class == "myItem" and presence of a LinkID attribute is sufficient to identify nodes requiring a click handler they could be identified using multiple CSS selectors. If this is not possible however, a query selector not using id can create a list of nodes to be checked for id, as for example:
function callMyFunction()
{ MyFunction(this.getAttribute("LinkID"), false);
}
function addClickHandlers()
{ var list = document.querySelectorAll("a[LinkID]")
var i, node;
for( i = 0; i < list.length; ++i)
{ node = list[i];
if(node.id == "myLink")
{ node.onclick=callMyFunction;
}
}
}
See also running a selector query on descendant elements of given node if of interest.
Related
I want to select an element if it has a css as display block then do this function. If the element has the css as display block then remove ('hide') class from the header class.. This is what I want to do.. Any help?
Well, there are two solutions depending on what you want:
Solution 1
Looping through all elements and removing hide class from the current element if it has display block value in its style.
var elements = document.getElementsByTagName("*");
for(let i = 0; i < elements.length; i++) {
if(elements[i].style.display == "block") {
elements[i].classList.remove("hide");
}
}
Solution 2
Getting the reference of the element via HTML id.
var element = document.getElementById("YourElementID");
if(element.style.display == "block") {
element.classList.remove("hide");
}
You can define an id like this in your HTML file:
<div id="YourElementID">Div</div>
I am assuming that you want to determine if the element has the "hide" class by checking its display style. you don't need to do that, you can easily check its class list by using the following code:
element.classList.contains("hide");
There are several ways of collecting all the elements with display: block and i am not sure, which one performs best - or whether it performs good at all.
If you want all the Element instances of the page, which have a computed style of display: block you can do something like:
var $els = Array.from(document.body.querySelectorAll('*')).filter(function($el) {
return getComputedStyle($el).display === 'block';
});
Or ES6:
const $els = Array.from(document.body.querySelectorAll('*')).filter($el => getComputedStyle($el).display === 'block');
If you want the Element instances which have display: block literally set in the style-attribute, you have to do something like this:
var $els = Array.from(document.body.querySelectorAll('*')).filter(function($el) {
return $el.style.display === 'block';
});
I think it would perform better, if the selector in querySelectorAll() would be a little more specific.
Another option would be to use the TreeWalker API, but then you have to do a mutation, because you have to iterate over all the elements and push them to an array:
var $els = [];
walker = document.createTreeWalker(document.body, NodeFilter.SHOW_ELEMENT);
while (walker.nextNode()) {
if (getComputedStyle(walker.currentNode).display === 'block') {
$els.push(walker.currentNode);
}
}
Once you have all your elements, you can do something with them.
A little bit more information would be helpful, especially what exactly you want to achieve, once you have the elements, because then i could also provide more help. Maybe provide a code example?
I was wondering if there is a possibility to HIDE anchor tags that refer to a particular URL.
I know there is possible to hide based on id like this with JavaScript:
document.getElementById('someID').style.display = 'none';
Check
But let's say I want to hide all anchor tags based on URL example: www.example.com
Check
Check
I want to hide the first anchor tag, not the second that refers to example2.com
Is this possible with pure JavaScript and not jQuery?
You can use document.querySelector to select bu attribute value like this.I have used no jquery the only javascript is used.
document.querySelector("[href='www.example.com']").style.display = 'none';
Check
Check
Simply loop through all anchor elements and then check their href:
var anchors = document.getElementsByTagName('a');
for (var i = 0; i < anchors.length; i++) {
if (anchors[i].href == 'https://example.com/') {
anchors[i].style.display = 'none';
}
}
Check
Check
You can use javascript to do the job. Use querySelector to get all the elements with same id. Then loop the ids and compare the href link value.
<script>
var elements = document.querySelectorAll("[id='someID']");
for(var i = 0; i < elements.length; i++) {
if (elements[i].getAttribute("href") === "www.example.com") {
elements[i].style.display='none';
}
}
</script>
Working fiddle link
You can make condition
var url = document.getElementsByTagName('a');
if (url.href = "www.example.com")
{
url.style.display = none;
}
It is not exact code. i provided you example .kindly try it and let me know. It is for single . if you have many tags then loop all those
I try to find an easy solution (I am a totally coding beginner, just use javascript in widgets of a "out of the box" page) for the following problem:
There are multiple attributes visitor can select by click Remove/Show
attribute a (Remove/Show)
attribute b (Remove/Show)
attribute c (Remove/Show)
a.s.o.
based on visitors "selection", I would like to show or hide the list of elements:
element 1 (attribute a and b) - Remove if "a" OR "b" has been selected
element 2 (attribute a) - remove if "a" has been selected
element 3 (attribute a and c) - remove, if "a" OR "c" has been selected
a.s.o.
I am able already to hide elements based on a "selection", but in my solution every element show and hide only based on the unique ID (and so also only on the single selection).
The Javascript I found for that is:
<script type="text/javascript">
//<![CDATA[
function swap(openlink,closelink, linkid, dataid)
{
if( document.getElementById(dataid).style.display == 'none')
{
document.getElementById(dataid).style.display='inline';
document.getElementById(linkid).firstChild.nodeValue=closelink;
} else
{
document.getElementById(dataid).style.display='none';
document.getElementById(linkid).firstChild.nodeValue=openlink;
}
}
//]]>
</script>
And than I could use this HTML Code to Remove/Show the elements:
attribute a Remove
attribute b Remove
attribute c Remove
And my element will be Remove/Show by this:
<div id="showmeA" style="display:inline">Element 1</div>
<div id="showmeB" style="display:inline">Element 2</div>
<div id="showmeB" style="display:inline">Element 3</div>
Is there an easy way to add 2 ids to one "element", so that for example Element 1 could be hidden by id=showmeA AND id=showmeB?
You said the issue yourself: IDs are unique.
This is exactly why you should use something else than id, and class attribute is perfectly fine as it does not have to be unique.
Then, this means that the function will not look for your elements using getElementById() but getElementsByClassName().
Note that this function get elements, this involves that you have to loop through these elements and hide / show the ones targeted.
function swap(openlink, closelink, linkid, dataclass) {
var elements = document.getElementsByClassName(dataclass);
for (var i = 0; i < elements.length; i++) {
var element = elements[i];
if(element.style.display == 'none') {
element.style.display='inline';
document.getElementById(linkid).firstChild.nodeValue=closelink;
} else {
element.style.display='none';
document.getElementById(linkid).firstChild.nodeValue=openlink;
}
}
}
Do not forget to replace id by class attributes to your HTML, you can put in as much as you want, they simply must be separated by a space:
<div class="showmeA showmeB">Element 1</div>
<div class="showmeB">Element 2</div>
<div class="showmeC">Element 3</div>
Here is an example that you can use to better understand the function and attributes used in your solution, this solves your issue: https://jsfiddle.net/sy2mxscf/
It is also important to inform you that inline Javascript is bad, you should reconsider your code when your Javascript skill will increase.
In order to solve the issue pointed out in the comments, you have to use some kind of counter and increment it when you hide the element, decrement it when you show element of one of his class, and displaying the associate element when this counter is 0.
This is also why you need two differentiated links: the "Remove" to increment, and the "Show" to decrement.
There are several way to implement this solution:
Use an associative array in Javascript
Use a custom attribute on the element
Add and remove specific classes
I chose the last one but this may be not the best one, this is just one of the possibilities.
https://jsfiddle.net/sy2mxscf/2/
The idea is to add or remove a custom "hidemeX" class. If you click on two different "Remove" links targeting the same element, two classes will be added. If you then click on any "Show" link, the associate class will be removed. But there is still a "hidemeX" class remaining until you click on the second link, so the element is not displayed thanks to CSS.
As Delgan says, its better to use class here, and you can use those <a>'s id as their class, so when you use your function swap, you can easily trace back to decide if the elements is selected, so the div should be removed.
Below is how you can separate javascript logic and html structure.
var swap = function(e) {
var close = 'Remove', open = 'Show';
var next = this.text === close ? open : close;
// Set the clicked <a>'s text.
this.text = next;
// Get divs that will affect by this <a>
var affectTarget = this.id;
// Affected div elements
var targets = document.getElementsByClassName(affectTarget);
var i, len = targets.length;
var visible;
var watch, wLen, j;
// For each <div> that will be affect by the clicked <a>, we have to chec :
for (i = 0; i < len; ++i) {
// Get the classes that used as a list to show which <a> will have a effect on it.
watch = targets[i].classList;
wLen = watch.length;
// visibilty is default to inline, if no <a> that it watches is selected, then it'll show
visible = "inline";
for (j = 0; j < wLen; ++j) {
// If any of the <a> it watches is selected, set the visibilty to none.
if (document.getElementById(watch[j]).text === open) {
visible = "none";
break;
}
}
targets[i].style.display = visible;
}
};
// For each switcher, we register a click event for it.
var switchers = document.querySelectorAll("a.showSwitcher");
var i, len = switchers.length;
for (i = 0; i < len; ++i) {
switchers[i].addEventListener('click', swap);
}
attribute a Remove
attribute b Remove
attribute c Remove
<hr/>
<div class="swaplinkA swaplinkB" style="display:inline">Element 1</div>
<div class="swaplinkA"style="display:inline">Element 2</div>
<div class="swaplinkA swaplinkC"style="display:inline">Element 3</div>
I'm attempting to add target="_blank" to links on a page depending on a checkbox click.
On the javascript side I have:
function newTab(v) {
if(v.tab.checked == true) {
document.getElementsByTagName('a').setAttribute('target', '_blank');
} else {
document.getElementsByTagName('a').setAttribute('target', '_self');
}
} //end function
And on the HTML side I have:
<form>
<input type="checkbox" name="tab" onclick="newTab(this.form)" />
<label>Open Links In New Tab?</label>
</form>
Gmail
Naturally it isn't as simple as I thought it would be, so it doesn't work.
The page contains over a dozen links so I need the checkbox to apply to all links on the page - why I used getElementsByTagName(). Any help appreciated!
EDIT:
Code that works is as follows:
function newTab(f) {
var els = document.getElementsByTagName('a'); //read anchor elements into variable
if(f.tab.checked == true) { //If the box is checked.
for (var i in els) {
els[i].setAttribute('target', '_blank'); //Add 'target="blank"' to the HTML
}
} else { // not checked...
for (var i in els) {
els[i].setAttribute('target', '_self'); //Add 'target="self" to HTML
}
}
} //end function.
getElementsByTagName() returns a nodeset. You need to iterate over it and apply the change to each one in turn. What you currently have is more like jQuery syntax, which handles this internally for you.
This would have shown up in the console. With JS issues, always check the console before wondering what's wrong.
var els = document.getElementsByTagName('p');
for (var i=0, len = els.length; i<len; i++)
els[i].setAttribute('name', 'value');
Also, with checkboxes use change, not click events, as someone might toggle them via the keyboard, not mouse. Lastly, you should look into handling your events centrally, not inline DOM-zero events specified in the HTML. Numerous reasons for this that are beyond the scope of this question.
I'm wondering if it's possible for a script to enable/disable all input elements on the page with some sort of toggle button.
I googled it but didn't find anything too useful except for this:
http://www.codetoad.com/javascript/enable_disable_form_element.asp
but I'm not sure how to edit it for the toggle.
Something like this would work:
var inputs=document.getElementsByTagName('input');
for(i=0;i<inputs.length;i++){
inputs[i].disabled=true;
}
A working example:
$().ready(function() {
$('#clicker').click(function() {
$('input').each(function() {
if ($(this).attr('disabled')) {
$(this).removeAttr('disabled');
}
else {
$(this).attr({
'disabled': 'disabled'
});
}
});
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js"></script>
<input type='text'></input>
<input type='text'></input>
<input type='text'></input>
<div id='clicker' style='background-color:#FF0000; height:40px; width:100px;'></div>
Here is a function to toggle all inputs on the page:
function toggle_inputs() {
var inputs = document.getElementsByTagName('input');
for (var i = inputs.length, n = 0; n < i; n++) {
inputs[n].disabled = !inputs[n].disabled;
}
}
It works by using the logical NOT operator (the exclamation point), which returns the opposite of the operand. For example, !true will return false. So by using !inputs[n].disabled, it will return the opposite of what it's currently set to, thereby toggling it.
If you need code to bind the click event to the button:
document.getElementById('your_button_id').onclick = toggle_inputs;
You can also use addEventListener, but see the linked page for more information, including compatibility with Internet Explorer. The code I gave above should work across all browsers with no trouble.
for (var i = 0; i < document.getElementyByTagName('input').length; i++) {
document.getElementsByTagName('input')[i].disabled = 'disabled';
}
http://code.google.com/p/getelementsbyclassname/
^^Robert Nyman has a "get elements by class" script. Basically you'd just assign all those input elements to the same class, and then do something like:
//Collapse all the nodes
function collapseNodesByClass(theClass){
var nodes = getElementsByClassName(theClass);
for(i = 0; i < nodes.length; i++){
nodes[i].style.display='none';
}
}
This is a piece of code I'm actually currently using to collapse everything with a given class name (it uses the script I mentioned above). But in any case I think the key to your problem is being able to refer to multiple elements at once, which that script will help you with.
Also the link in your question didn't work for me :(.