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Bootstrap tooltip gets stuck if element changes when visible

I am using Bootstrap 5.1.3 (in Rails). Our application consists of dynamically loaded data, that is not always the fastest to load (some complicated SQL queries / huge amounts of data to make calculations with).
We use tooltips on different elements to show extra information / indicate (click)actions. Tooltips are added like this.
On the element that should get the tooltip:
data-bs-toggle="tooltip" data-bs-placement="top" title={question.questionDescription}
In that Bootstrap file:
componentDidUpdate(previousProps, previousState)
{
// Enable all tooltips.
TooltipHelper.enableTooltips([].slice.call(document.querySelectorAll('[data-bs-toggle="tooltip"]')));
}
And then TooltipHelper:
static enableTooltips(targets)
{
var enabledTooltips = targets.map(function (target) {
return new bootstrap.Tooltip(target, { trigger: 'hover' });
});
}
The tooltips work, but don't always go away. My guess is that when a tooltip is shown (because hovering over something) and then that element (or a parent of that element) gets changed, for example the content of it, the tooltip stays there. No matter if I click somewhere of hover over other elements.
I've tried adding a delay within the enableTooltips()-function. This seems to work, but the needed delay is too big. Also, it still breaks when elements are dynamically added and content is loaded, when the page isn't reloaded.
My hacky solution:
static enableTooltips(targets)
{
setTimeout(function() {
var enabledTooltips = targets.map(function (target) {
return new bootstrap.Tooltip(target, { trigger: 'hover' });
});
}, 5000);
}
Anyone know of a solution? Thanks

Jscroll pagination plugin

i have download this good plugin
http://andersonferminiano.com/jqueryscrollpagination/
and i use this code for do a call to my db and show all the result. The my problem is that i can't stop the showing results when are finish in the database, i wouold like stop the pagination and no repeat the same result. how can i do it? thank you so much
$(function(){
$('#content').scrollPagination({
'contentPage': 'democontent.html', // the page where you are searching for results
'contentData': {}, // you can pass the children().size() to know where is the pagination
'scrollTarget': $(window), // who gonna scroll? in this example, the full window
'heightOffset': 10, // how many pixels before reaching end of the page would loading start? positives numbers only please
'beforeLoad': function(){ // before load, some function, maybe display a preloader div
$('.loading').fadeIn();
},
'afterLoad': function(elementsLoaded){ // after loading, some function to animate results and hide a preloader div
$('.loading').fadeOut();
var i = 0;
$(elementsLoaded).fadeInWithDelay();
if ($('#content').children().size() > 100){ // if more than 100 results loaded stop pagination (only for test)
$('#content').stopScrollPagination();
}
}
});
// code for fade in element by element with delay
$.fn.fadeInWithDelay = function(){
var delay = 0;
return this.each(function(){
$(this).delay(delay).animate({opacity:1}, 200);
delay += 100;
});
};
});

That plugin actually isn't very good. I'm looking at the plugin's code, and sure enough, it doesn't provide a way to detect when you're at the end of the content.
If you go to the plugin page and scroll down, it appears to be working quite nicely. However, when you look at the file democontent.html (he's hidden the text, you have to view the source) where the data is being retrieved from, you'll see it's only 17 items. But, it keeps loading bogus data as you scroll down.
Not only does the plugin not detect the end of the data, but it also doesn't provide a way of stopping at all. If you'll notice, Anderson told the plugin to stop after 100 items are loaded, but he did this only in his example instead of writing this feature into the plugin.
So, that's why your content isn't stopping. You could try modifying his plugin yourself, but if you'd rather just change plugins, I'd recommend Infinite Scroll, by Paul Irish.

You can use mkscroll plugin with is provide you more functionality link for mk scroll is below.
https://github.com/maulikkanani/Scroll-Pagination
jQuery(window).mkscroll({
limit:10,
total:100,
});
there are many other option in that.

If any one phasing the problem here is the solution: the jscroll will stop the loading the content once the 'next page' link is not available.. so please check when you want to stop loading the content then 'next page' link is not getting loaded in the last content which is appended.

infinite scroll pagination javascript implementation issues

I am trying to implement an infinite scroll pagination with javascript in jsfiddle but i am having issues getting it to work properly. I am not seeing the fading in when scrolling and when i reach the end of the content i am supposed to get the message that there is no more data but instead it says it is waiting for more data.
The original example: http://andersonferminiano.com/jqueryscrollpagination/
My implementation: http://jsfiddle.net/jsuHD/
I added an External Resource to the jsfiddle: scrollpagination.js
I think my problem is with the javascript and not knowing what to pass in as contentPage
$(function(){
$('#content').scrollPagination({
'contentPage': 'http://jsfiddle.net/jsuHD/', // the url you are fetching the results
'contentData': {}, // these are the variables you can pass to the request, for example: children().size() to know which page you are
'scrollTarget': $(window), // who gonna scroll? in this example, the full window
'heightOffset': 10, // it gonna request when scroll is 10 pixels before the page ends
'beforeLoad': function(){ // before load function, you can display a preloader div
$('#loading').fadeIn();
},
'afterLoad': function(elementsLoaded){ // after loading content, you can use this function to animate your new elements
$('#loading').fadeOut();
var i = 0;
$(elementsLoaded).fadeInWithDelay();
if ($('#content').children().size() > 100){ // if more than 100 results already loaded, then stop pagination (only for testing)
$('#nomoreresults').fadeIn();
$('#content').stopScrollPagination();
}
}
});
// code for fade in element by element
$.fn.fadeInWithDelay = function(){
var delay = 0;
return this.each(function(){
$(this).delay(delay).animate({opacity:1}, 200);
delay += 100;
});
};
});

If you fire up the console [f12 in google chrome] you will see that when you reach the end of the page a 403 forbidden request is made to jsFiddle itself. Yes I think the problem is in what you are passing to contentPage.
Here's a working fiddle http://jsfiddle.net/jsuHD/10/ of your solution. When you load the html from an external source which allows you to get the resource you want, it works as expected.
//load the html from external resource
'contentPage': 'http://dl.dropbox.com/u/4001846/sample.html'

How to go about writing a Javascript pre-loader?

I'm not talking about how to pre-load images using Javascript, I am thinking more along the lines of a Flash preloader which displays some sort of feedback while the SWF loads.
The site in question has heavy Javascript usage and requires many large images at page load so I wish to hide the site behind a loading screen till the initial images are all loaded.

I wrote a jQuery plugin called waitForImages that lets you do this.
The callbacks allow you to do whatever when each image has loaded...
$('body').waitForImages(
function() {
// Called when all images have loaded.
},
function(loaded, total, success) {
// Called once each individual image has loaded.
// `loaded` is the number of images loaded so far.
// `total` is the total number of images to load.
// `success` is `true` if the image loaded and `false` if the image failed to load.
// `this` points to the native DOM `img` element.
},
// Set the third argument to `true` if you'd like the plugin to look in the CSS
// for references to images.
true
);
jsFiddle.

I have one written when I first learned JavaScript. I'm going to try to find it in a second. The basic idea is to have a hidden element that's outside the page, and load your image in there.
Beware, ugly code as I wrote this when i started. Also it probably is not exactly what you're looking for, though there are good comments. Just modify it and make it a generic function. Based on jQuery, for a javascript gallery:
this.preload = function(){
/*
* Preloads all the image to a hidden div so the animation won't glitch.
*/
if (document.getElementById("preload")){ // Checks for existance.
var preload = document.getElementById("preload"); // Gets the preload div if it exists.
} else {
var preload = document.createElement("preload"); // Creates the preload div if it doesn't exist.
$(preload).attr("id", "preload");
}
for (var i=0; i<this.aNodes.length; i++){ // Get all the image links
var img = document.createElement("img"); // Loads all the image in a hidden div.
$(img).attr("src", this.aNodes[i].href);
preload.appendChild(img);
}
}

How to show a spinner while loading an image via JavaScript

I'm currently working on a web application which has a page which displays a single chart (a .png image). On another part of this page there are a set of links which, when clicked, the entire page reloads and looks exactly the same as before except for the chart in the middle of the page.
What I want to do is when a link is clicked on a page just the chart on the page is changed. This will speed things up tremendously as the page is roughly 100kb large, and don't really want to reload the entire page just to display this.
I've been doing this via JavaScript, which works so far, using the following code
document.getElementById('chart').src = '/charts/10.png';
The problem is that when the user clicks on the link, it may take a couple of seconds before the chart changes. This makes the user think that their click hasn't done anything, or that the system is slow to respond.
What I want to happen is display a spinner / throbber / status indicator, in place of where the image is while it is loading, so when the user clicks the link they know at least the system has taken their input and is doing something about it.
I've tried a few suggestions, even using a psudo time out to show a spinner, and then flick back to the image.
A good suggestion I've had is to use the following
<img src="/charts/10.png" lowsrc="/spinner.gif"/>
Which would be ideal, except the spinner is significantly smaller than the chart which is being displayed.
Any other ideas?

I've used something like this to preload an image and then automatically call back to my javascript when the image is finished loading. You want to check complete before you setup the callback because the image may already be cached and it may not call your callback.
function PreloadImage(imgSrc, callback){
var objImagePreloader = new Image();
objImagePreloader.src = imgSrc;
if(objImagePreloader.complete){
callback();
objImagePreloader.onload=function(){};
}
else{
objImagePreloader.onload = function() {
callback();
// clear onLoad, IE behaves irratically with animated gifs otherwise
objImagePreloader.onload=function(){};
}
}
}

You could show a static image that gives the optical illusion of a spinny-wheel, like these.

Using the load() method of jQuery, it is easily possible to do something as soon as an image is loaded:
$('img.example').load(function() {
$('#spinner').fadeOut();
});
See: http://api.jquery.com/load-event/

Use the power of the setTimeout() function (More info) - this allows you set a timer to trigger a function call in the future, and calling it won't block execution of the current / other functions (async.).
Position a div containing the spinner above the chart image, with it's css display attribute set to none:
<div> <img src="spinner.gif" id="spinnerImg" style="display: none;" /></div>
The nbsp stop the div collapsing when the spinner is hidden. Without it, when you toggle display of the spinner, your layout will "twitch"
function chartOnClick() {
//How long to show the spinner for in ms (eg 3 seconds)
var spinnerShowTime = 3000
//Show the spinner
document.getElementById('spinnerImg').style.display = "";
//Change the chart src
document.getElementById('chart').src = '/charts/10.png';
//Set the timeout on the spinner
setTimeout("hideSpinner()", spinnerShowTime);
}
function hideSpinner() {
document.getElementById('spinnerImg').style.display = "none";
}

Use CSS to set the loading animation as a centered background-image for the image's container.
Then when loading the new large image, first set the src to a preloaded transparent 1 pixel gif.
e.g.
document.getElementById('mainimg').src = '/images/1pix.gif';
document.getElementById('mainimg').src = '/images/large_image.jpg';
While the large_image.jpg is loading, the background will show through the 1pix transparent gif.

Building on Ed's answer, I would prefer to see something like:
function PreLoadImage( srcURL, callback, errorCallback ) {
var thePic = new Image();
thePic.onload = function() {
callback();
thePic.onload = function(){};
}
thePic.onerror = function() {
errorCallback();
}
thePic.src = srcURL;
}
Your callback can display the image in its proper place and dispose/hide of a spinner, and the errorCallback prevents your page from "beachballing". All event driven, no timers or polling, plus you don't have to add the additional if statements to check if the image completed loading while you where setting up your events - since they're set up beforehand they'll trigger regardless of how quickly the images loads.

Some time ago I have written a jQuery plugin which handles displaying a spinner automatically http://denysonique.github.com/imgPreload/
Looking in to its source code should help you with detecting when to display the spinner and with displaying it in the centre of the loaded image.

I like #duddle's jquery method but find that load() isn't always called (such as when the image is retrieved from cache in IE). I use this version instead:
$('img.example').one('load', function() {
$('#spinner').remove();
}).each(function() {
if(this.complete) {
$(this).trigger('load');
}
});
This calls load at most one time and immediately if it's already completed loading.

put the spinner in a div the same size as the chart, you know the height and width so you can use relative positioning to center it correctly.

Aside from the lowsrc option, I've also used a background-image on the img's container.

Be aware that the callback function is also called if the image src doesn't exist (http 404 error). To avoid this you can check the width of the image, like:
if(this.width == 0) return false;

#iAn's solution looks good to me. The only thing I'd change is instead of using setTimeout, I'd try and hook into the images 'Load' event. This way, if the image takes longer than 3 seconds to download, you'll still get the spinner.
On the other hand, if it takes less time to download, you'll get the spinner for less than 3 seconds.

I would add some random digits to avoid the browser cache.