According to This page I was able to remove all the CSS preloaded and added on the webpage using that. I wanted to implement a button system where "onclick" = enable/disable webpage CSS even the ones pre-loaded by my web-host. I would like to eliminate the style tags to prevent lags for my website users. I prefer using the script that I have linked above unless there is another alternative that works better. Is it possible to enable CSS onclick the same button to disable? If not is it possible, can it be done with this quick? example with the preferred script below:
if (disable) {
style = "disable";
} else {
location.reload();
}
PREFERRED SCRIPT:
function removeStyles(el) {
el.removeAttribute('style');
if(el.childNodes.length > 0) {
for(var child in el.childNodes) {
/* filter element nodes only */
if(el.childNodes[child].nodeType == 1)
removeStyles(el.childNodes[child]);
}
}
}
removeStyles(document.body);
What about a different aproach?
Add initially a class to a body called 'styled' for example
<body class="styled">
use it as a main selector in your css definitions
<style>
.styled a { ... }
.styled h1 { .... }
</style>
then an example jquery script to toggle the class:
<script>
$(function() {
$('#myswitch').click(function() {
$('body').toggleClass('styled');
});
});
</script>
when class is present, the page will be styled, when absent there will be no styling.
Of coures there could be better aproach, but this is the first thing which pops up in my mind
To remove all style on an element, you could do
function removeStyles(el) {
el.style = {};
}
If you want to enable/disable the CSS on the page, then the goal is not to merely remove all the styles on the page, but you will need to save them somewhere also so they can be recalled when the user re-clicks the button. I would recommend having jQuery to help you with this, and it could be done the following way:
var style_nodes = $('link[rel="stylesheet"], style');
style_nodes.remove();
$('*').each(function(num, obj) {
var style_string = $(obj).attr("style");
if (style_string) {
$(obj).data("style-string", style_string);
$(obj).attr("style", "");
}
});
Now you've saved the stylesheets and style DOM nodes inside of style_nodes, and the actual style attribute inside of a jQuery data attribute for that specific DOM node. When you click to add the CSS back to the page, you can do the following:
$('head').append(style_nodes);
$('*').each(function(num, obj) {
if ($(obj).data("style-string"))
$(obj).attr("style", $(obj).data("style-string"));
});
Check out this JS Fiddle I put together to demonstrate it:
https://jsfiddle.net/5krLn3w1/
Uses JQuery, but I'm sure most frameworks should give you similar functionality.
HTML:
<h1>Hello World</h1>
Turn off CSS
Turn on CSS
JS:
$(document).ready(function() {
$('a#turn_off').click(function(evt) {
evt.preventDefault();
var css = $('head').find('style[type="text/css"]').add('link[rel="stylesheet"]');
$('head').data('css', css);
css.remove();
});
$('a#turn_on').click(function(evt) {
evt.preventDefault();
var css = $('head').data('css');
console.info(css);
if (css) {
$('head').append(css);
}
});
});
CSS:
body {
color: #00F;
}
h1 {
font-size: 50px;
}
Related
I have the following DOM element change function using vanilla JavaScript where I change the span element that contains some text string of the DOM with a page load event.
With the following code, the DOM elements are changed as expected. However, they still see a minimal fraction of flickering before the DOM element change for the variable desktop and mobile.
Example of the flickering scenario:
I see the tag span "Text I want to change" for a fraction of second.
I see the changed tag span "text1 changed" after the content has fully loaded.
I think this is happening because the DOM changes are applied when the DOM content of the page is fully loaded. I would like to hide the existing tag elements until the changes have been applied and then display them.
The elements structure for desktop and mobile I want to manipulate is like the following:
<span class="first-headline target-span">Text I want to change</span>
See the concept below:
var changesObj = {
"us": {
title: "text1 changed"
},
"eu": {
title: "text2 changed"
}
};
function changes() {
var webshop = changesObj[window.location.pathname.split('/')[1]];
console.log(webshop);
var changesText;
if (!webshop) {
console.log('webshop not found');
}
changesText = webshop.title;
if (document.querySelector('.target-span').innerText.length > 0) {
var desktop = document.querySelector('.target-span');
console.log(desktop);
desktop.innerText = changesText;
console.log(desktop.innerText);
console.log("applied changes for dekstop");
}
if (document.querySelector('.target-span').innerText.lenght > 0) {
var mobile = document.querySelector('.target-span');
mobile.innerText = changesText;
console.log(mobile.innerText);
console.log("applied changes for mobile");
}
}
function invokeChanges() {
document.addEventListener("DOMContentLoaded", function () {
changes();
});
}
invokeChanges();
Is there a way to initially hide the DOM element until the change to the existing element has been applied and then show it?
I was thinking of using something inline CSS rules like the following:
Set .style.visbility='hidden' and when the text content is changed to show it with .style.visbility='visble'.
But I'm not sure how this solution should be appropriately implemented in my code.
There are a few reasons as to why it's flickering, but two preventative steps you can take:
Use defer on your script tag <script defer>, as this lets the browser handle the order your scripts are run instead of DOMContentLoaded. You also get to avoid the changes wrapper function.
As suggested by this question (and your own reasoning) attach inline CSS / a CSS file to the page to set the text as invisible, then mark it as visible
If it doesn't affect the layout of your page too much, you can also opt to dynamically generate the element instead.
However, do note that regardless of any of these, these still require JS to be executed and may still have a delay. If you are able to use it, you may be interested in prerendering your webpage - from your JS code, it looks for the route name if its eu or us, which means your page is pre-renderable.
Quick & Dirty:
Place the script tag just below your span tag:
<span class="first-headline target-span">Text I want to change</span>
<script>
var changesObj = {
"us": {
title: "text1 changed"
},
"eu": {
title: "text2 changed"
}
};
function changes() {
var webshop = changesObj[window.location.pathname.split('/')[1]];
console.log(webshop);
var changesText;
if (!webshop) {
console.log('webshop not found');
}
changesText = webshop.title;
if (document.querySelector('.target-span').innerText.length > 0) {
var desktop = document.querySelector('.target-span');
console.log(desktop);
desktop.innerText = changesText;
console.log(desktop.innerText);
console.log("applied changes for dekstop");
}
if (document.querySelector('.target-span').innerText.lenght > 0) {
var mobile = document.querySelector('.target-span');
mobile.innerText = changesText;
console.log(mobile.innerText);
console.log("applied changes for mobile");
}
}
changes();
</script>
This way you avoid the asynchronous code part.
In any case you need to wait until the DOM has been loaded before you can manipulate it. Using an even listener for DOMContentLoaded would be the way to go. So, three things need to happen:
Wait for the DOM to load
Find the elements and change the text
Make the elements visible. You can either use the property visibility: hidden or display: none. Difference is that with visibility: hidden the element will still take up space. So, the choice depends on the context.
In the first example I add a timeout so that you can see what the page looks like just before the text is changed. I also styled the <p> (display: inline-block) so that you can see the size of the hidden span.
window.location.hash = "us"; // for testing on SO
var changesObj = {
"us": { title: "text1 changed" },
"eu": { title: "text2 changed" }
};
function changes(e) {
//let webshop = changesObj[window.location.pathname.split('/')[1]];
let webshop = changesObj[window.location.hash.substring(1)]; // for testing on SO
if (webshop) {
[...document.querySelectorAll('.target-span')].forEach(span => {
span.textContent = webshop.title;
span.classList.add('show');
});
}
}
document.addEventListener('DOMContentLoaded', e => {
setTimeout(changes, 1000);
});
p {
border: thin solid black;
display: inline-block;
}
.target-span {
visibility: hidden;
}
.target-span.show {
visibility: visible;
}
<p>
<span class="first-headline target-span">Text I want to change</span>
</p>
<p>
<span class="first-headline target-span">Text I want to change</span>
</p>
In the second example I combined all the code into one HTML page. Notice that the style is defined in the header. So, when the DOM is passed the CSS will be passed as well without having to load a external style-sheet (well, there are tricks for that as well, but out of scope for this answer).
<html>
<head>
<style>
p {
border: thin solid black;
}
.target-span {
visibility: hidden;
}
.target-span.show {
visibility: visible;
}
</style>
<script>
window.location.hash = "us"; // for testing on SO
var changesObj = {
"us": {title: "text1 changed"},
"eu": {title: "text2 changed"}
};
function changes(e) {
//let webshop = changesObj[window.location.pathname.split('/')[1]];
let webshop = changesObj[window.location.hash.substring(1)]; // for testing on SO
if (webshop) {
[...document.querySelectorAll('.target-span')].forEach(span => {
span.textContent = webshop.title;
span.classList.add('show');
});
}
}
document.addEventListener('DOMContentLoaded', changes);
</script>
</head>
<body>
<p>
<span class="first-headline target-span">Text I want to change</span>
</p>
<p>
<span class="first-headline target-span">Text I want to change</span>
</p>
</body>
</html>
I will need to put 2 different actions on a single link which would have an active/inactive state, right now I only know how to do one at the time, something like this (active):
State One
And I would like to have another one on same click (inactive), is there a way to have this dynamically changed? The label shouldn't change, except for color for example - style.
On the other side, it would be a great thing if I could show the list of active items as well, something like:
Active states: State one, State two, State ...
I recommend something other than an A tag for what you're doing. I also recommend the modern equivalent of an onclick, an event listener. I also recommend assigning and toggling the class.
State One
I have removed your onclick and put it into an event listener. I've added a class, so you can toggle it.
function classToggle() {
this.classList.toggle('class123');
this.classList.toggle('class456');
}
This toggles your class, thus allowing you to change the behavior of the link based on the class. Active/Inactive or Class123/Class456 whatever you want to use will work.
document.querySelector('#myDiv').addEventListener('click', classToggle);
This is your listener. It applies the classToggle function on click. You can do this with a div/button/whatever. Personally I'd change the A tag to a Div.
<div id="myElem" class="class123">click here</div>
And here is an example of this stuff working and changing based on the toggle and classes.
function classToggle() {
this.classList.toggle('class123');
this.classList.toggle('class456');
}
document.querySelector('#myElem').addEventListener('click', classToggle);
document.querySelector('#myElem').addEventListener('click', mogrify);
function mogrify(){
if (document.querySelector('#myElem').classList.contains('class123')) {
document.querySelector('#myElem').style.backgroundcolor = "#54C0FF"
document.querySelector('#myElem').innerText = "State Two";
} else {
document.querySelector('#myElem').style.backgroundcolor = "#FF8080"
document.querySelector('#myElem').innerText = "State One";
}
}
.class123 {
color: #f00;
}
.class456 {
color: #00f;
}
State One
I think I got it to work, here's my code, please let me know if good enough.
A href:
State One
js:
<script>
function toggleState(a) {
if ( a.className === 'visible' ) {
HideOneState('state_One', gameInstance);
a.className = '';
} else {
ShowOneState('state_One', gameInstance);
a.className = 'visible';
}
}
</script>
#shandoe2020 has a good answer but here is the "old way" which is pretty easy to understand too. It can be adapted to links (or anything else) quite easily.
<!DOCTYPE html>
<html>
<head>
<style>
.my-button { width:150px; height:150px; }
.my-red { background-color:#ff0000; }
.my-blue { background-color:#0000ff; }
</style>
<script>
/* toggle the state of my-red and my-blue class */
function toggle()
{
/* yeah yeah, hardcoding the item to change is bad */
var elem = document.getElementById("btn")
elem.classList.toggle("my-red")
elem.classList.toggle("my-blue")
}
</script>
</head>
<body>
<div>
<p><button id="btn" class="my-button my-red" onclick="toggle()">Button</button></p>
</div>
</body>
</html>
I am working on a class project and need to be able to toggle the background color of a transparent png on click. I have been working through a number of examples from the site, but I can't get it working. I am a total novice at Javascript and haven't had luck trying to plug in jQuery code either.
Here is the targeted section:
<div class="expenseIcon"><a href="#">
<img src="images/mortgage.png"></a><br/>
<p>Rent or Mortgage</p>
</div>
On clicking the linked image, the goal is for the background on the image to change to green. Clicking it again would change it back to the default, white. Here's the CSS I'd like to toggle on/off with click.
.colorToggle {
background: #A6D785;
}
I had tried adding class="iconLink" to the href and class="iconBox" to the image with the following Javascript adapted from another post, but it didn't work.
var obj = {};
$(document).ready(function () {
$(".iconLink").click(function () {
var text = $(this).find(".iconBox");
obj.var1 = text;
//alert(obj.var1);
//return false;
$('.iconBox').removeClass('colorToggle');
$(this).addClass('colorToggle')
});
});
Any advice would be greatly appreciated!
Let's break down what is happening with your current code when you click the link.
var obj = {};
$(document).ready(function () {
$(".iconLink").click(function () {
var text = $(this).find(".iconBox");
obj.var1 = text;
$('.iconBox').removeClass('colorToggle');
$(this).addClass('colorToggle')
});
});
JQuery finds all elements with the classname "iconBox". In your case, this is the img element. The reference to that element is then saved in "obj.var1". You do not end up doing anything with this reference, so these two lines can be removed.
All elements with the class "iconBox" have the class "colorToggle" removed. Your img element didn't have this class on it, so nothing happens.
The class "colorToggle" is added to the anchor element. Yes! Now the element wrapping the img has a background color.
Unfortunately, clicking the anchor tag again won't do anything, since the anchor tag will already have the "colorToggle" class and all we would be doing would be trying to add it again. Hmm. Let's try changing addClass to toggleClass. Here's our new code:
$(document).ready(function () {
$(".iconLink").click(function () {
$(this).toggleClass('colorToggle');
}
});
Also, note that because we're working with the anchor element, the p element won't be affected by this change. If you want the entire div to change background colors, use this line instead:
$(".expenseIcon").toggleClass('colorToggle');
Using the given markup:
<!-- to toggle the bg-color onClick of anchor tag -->
<div class="expenseIcon">
<a href="#">
<img src="images/mortgage.png">
</a>
<br/>
<p>Rent or Mortgage</p>
</div>
since the question asks for javascript, heres an option for updating the background-color of an element using the built-in js.style method
//get a handle on the link
//only one element w/ className 'expenseIcon'
//first child of 'expenseIcon' is the anchor tag
var link = document.getElementsByClassName('expenseIcon')[0].children[0];
//get a handle on the image
var image = link.children[0];
//listen for click on link & call bgUpdate()
link.addEventListener('click', bgUpdate, false);
function bgUpdate() {
if(image.style.backgroundColor === 'lightgoldenrodyellow'){
image.style.backgroundColor = 'aliceblue';
} else if (image.style.backgroundColor === 'aliceblue') {
image.style.backgroundColor = 'lightgoldenrodyellow';
}
else console.log('image bgColor: ' + image.style.backgroundColor);
}
a similar example
css
.expenseIcon{
background: red;
}
.colorToggle {
background: blue;
}
jquery
$(".expenseIcon").click(function () {
$('.expenseIcon').toggleClass('colorToggle');
});
By default, the div will have expenseIcon background. ToggleClass will toggle the div class with colorToggle so will override the previous color.
You don't need an hyperlink tag A to manage clicks, just put it on the DIV.
how to execute something on mouse enter? like show in the code down below.
for(x=1; isset($_COOKIE["link$x"]); $x++)
echo <div id="'.$x.'" OnMouseEnter="myfunction('.$x.')">
}
and then in javascript
function myfunction(which){
// doing stuff on id with "which"
}
onmouseenter is specific to IE, so use onmouseover:
myElement.onmouseover = function()
{
document.getElementById(which).style.backgroundColor = 'red';
}
yes, it's as simple as that... notice I changed red to 'red', because I don't think you've defined red. This is how to do it in Javascript, though it would be much simpler to do it in CSS with :hover, but you're asking for Javascript.
If you just want to apply a style on mouseover, you don't need JavaScript. The CSS :hover pseudo-selector should work fine:
#elementId {
background: white;
}
#elementId:hover {
background: red;
}
You don't even have to go that far...
you can do this simply and easily using a :hover pseudo class.
in your css create two rules
.myHoverDiv
{
/* any styles you need here that show when not hovered over */
}
.myHoverDiv:hover
{
/* any styles here that should change when the mouse hovers over it */
background-color: red;
}
then on your tag use
<div class="myHoverDiv"> ... div inner contents here ... </div>
your div's style will change as expected when the mouse is hovered over it
As kumar_v asked too, i guess you shoud use "OnMouseOver" instead of "OnMouseEnter" to get a "hover"-effect.
So your PHP-code should be like that:
for($x=1; isset($_COOKIE["link$x"]); $x++) {
echo '<div id="'.$x.'" OnMouseOver="myfunction('.$x.')">test</div>';
}
and Javascript:
function myfunction(which){
document.getElementById(which).style.backgroundColor = "red";
}
better you handle your javascript in one block and I suggest you to make a handler to do that for you, if you use common javascript library such as jQuery and mouseover, that becomes super easier to handle and debug, remember add jQuery library to head of page.
server-side:
echo '<div id="handler_id">';
for(x=1; isset($_COOKIE["link$x"]); $x++)
echo <div id="'.$x.'">
}
echo '</div>';
client-side, this part is in within <script /> tag or in separated js file:
(function(window, $) {
var window.handler = handler = {
init: function() {
$('#handler_id > div').mouseover(function(){
console.log("mouse is over", this);
});
}
}
$(function(){ handler.init(); });
})(window, jQuery)
I am trying to hide a div when another one is visible.
I have div 1 and div 2.
If div 2 is showing then div 1 should hide and if div 2 is not showing then div 1 should be visible/unhide.
The function would need to be function/document ready upon page load.
I've tried this but I'm not having any luck, can someone please show me how I can do this.
<script>
window.onLoad(function () {
if ($('.div2').is(":visible")) {
$(".div1").fadeOut(fast);
} else if ($('.div2').is(":hidden")) {
$('.div1').fadeIn(fast);
}
});
</script>
Add a class of hidden to each div, then toggle between that class using jQuery. By the way, window.onload is not a function, it expects a string like window.onload = function() {}. Also, put fast in quotations. I don't know if that's required, but that's how jQuery says to do it.
<div class="div1"></div>
<div class="div2 hidden"></div>
.hidden { display: none }
$(document).ready(function() {
if($(".div1").hasClass("hidden")) {
$(".div2").fadeIn("fast");
}
else if($(".div2").hasClass("hidden")) {
$(".div1").fadeIn("fast");
}
});
You should pass a string to the .fadeIn() and .fadeOut() methods.
Instead of .fadeIn(fast) it'll be .fadeIn("fast"). Same for .fadeOut().
And in general since you're already using jQuery it's better to wrap your code like this:
$(function () {
// Code goes here
});
It looks like you're using jquery selectors (a javascript library). If you're going to use jquery make sure the library is loaded properly by including it in the document header (google makes this easy by hosting it for you <script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js"></script>)
With jQuery loaded you can do it like this
$(document).ready(function(){
if ($('.div1').is(":visible")) {
$('div2').hide();
}
else if ($('.div2').is(":visible")) {
$('div1').hide();
}
});
WORKING EXAMPLE: http://jsfiddle.net/HVDHC/ - just change display:none from div 2 to div 1 and click 'run' to see it alternate.
You can use setTimeout or setInterval to track if these divs exists
$(function() {
var interval = window.setInterval(function() {
if($('#div2').hasClass('showing')) {
$('#div1').fadeOut('fast');
}
if($('#div2').hasClass('hidden')) {
$('#div1').fadeIn('fast');
}
}, 100);
// when some time u don't want to track it
// window.clearInterval(interval)
})
for better performance
var div1 = $('#div1')
, div2 = $('#div2')
var interval ....
// same as pre code