I'm currently working on a private dashboard. This dashboard should have changing background images that changes every minute (should be no problem to switch it to an hour or 20 seconds if I got it working then).
In order to do so, I registered for the [Pixabay API][1] and created the following API request
https://pixabay.com/api/?key=[my_key]f&q=nature&image_type=photo&orientation=horizontal&min_width=1920&min_height=1080&page=1&per_page=100
With that request, I get an array of 100 elements, each one containing the following information:
comments: 639
downloads: 785498
favorites: 3020
id: 736885
imageHeight: 1195
imageSize: 186303
imageWidth: 1920
largeImageURL: "https://pixabay.com/get/51e3d34b4257b108f5d0846096293076123ddee2504c704c7c2879d79048c05a_1280.jpg"
likes: 3966
pageURL: "https://pixabay.com/photos/tree-sunset-amazing-beautiful-736885/"
previewHeight: 93
previewURL: "https://cdn.pixabay.com/photo/2015/04/23/22/00/tree-736885_150.jpg"
previewWidth: 150
tags: "tree, sunset, amazing"
type: "photo"
user: "Bessi"
userImageURL: "https://cdn.pixabay.com/user/2019/04/11/22-45-05-994_250x250.jpg"
user_id: 909086
views: 2042402
webformatHeight: 398
webformatURL: "https://pixabay.com/get/51e3d34b4257b10ff3d8992cc62f3f79173fd9e64e507440722d78d39248c7_640.jpg"
webformatWidth: 640
From these 100 elements, I then randomly select one, take the largeImageURL and set it as background, together with a semi-transparent dark overlay to be able to read the text on top of it better. All this is done within a setInterval, so it happens every x milliseconds.
This is the code for it:
setInterval(function(){
$.post('getBackgroundImages.php', { }, function(data) {
var imageCollection = JSON.parse(data);
var imageNumber = Math.floor(Math.random() * 100);
var imageLink = imageCollection.hits[imageNumber].largeImageURL;
$('body').css("background","linear-gradient(rgba(0,0,0,.3), rgba(0,0,0,.3)),url('"+imageLink+"')");
});
},60000);
`getBackgroundImages.php' does nothing more then printing the content of the API-request.
The question now is the following: In the implemented solution, everything works, the new photo is displayed as background and switching works. However, the background is always set to a grey background for about half a second, before the image is displayed, which looks really not good, especially when often switching images.
What I'd like to get is a switching of the background without this grey background for a short time, propably even with a transition, so the change is not so abrupt...
I found a solution to first display a blured preview of the image before display the full resolution one. However, I think that this shouldn't be needed, as basically, the image has enough time to load and the background should change AFTER the image has loaded.. I do not care, if the change happens every 62 seconds, even though I set it to 60 seconds, because the image needs to load first.
Can anybody give me a hint on how to get this working better?
Thanks in advance!
[1]: https://pixabay.com/api/docs/
Maybe the most simple would be to alternate between two containers that works like backgrounds :
HTML :
<body>
<div class='bg' id='firstBg'></div>
<div class='bg' id='secondBg'></div>
<...Your Stuff...>
</body>
CSS :
body {
background: transparent;
}
.bg {
position: fixed;
left: 0;
top: 0;
width: 100vw;
height: 100vh;
background-position: center;
z-index: -1;
background-size: cover;
transition: 3s ease-in;
}
#secondBg {
display: none;
}
JS :
setInterval(function(){
$.post('getBackgroundImages.php', { }, function(data) {
var imageCollection = JSON.parse(data);
var imageNumber = Math.floor(Math.random() * 100);
var imageLink = imageCollection.hits[imageNumber].largeImageURL;
if ($('#firstBg').css('display') == 'none') {
$('#firstBg').css("background-image","url('"+imageLink+"')");
$('#firstBg').fadeIn();
$('#secondBg').fadeOut();
}
else {
$('#secondBg').css("background-image","url('"+imageLink+"')");
$('#secondBg').fadeIn();
$('#firstBg').fadeOut();
}
});
},60000);
I did the following solution now, thanks to the hint of #zero298.
<script>
function loadImages (images) {
// each image will be loaded by this function.
// it returns a Promise that will resolve once
// the image has finished loading
let loader = function (src) {
return new Promise(function (resolve, reject) {
let img = new Image();
img.onload = function () {
// resolve the promise with our url so it is
// returned in the result of Promise.all
resolve(src);
};
img.onerror = function (err) {
reject(err);
};
img.src = src;
});
};
// create an image loader for each url
let loaders = [];
images.forEach(function (image) {
loaders.push(loader(image));
});
// Promise.all will return a promise that will resolve once all of of our
// image loader promises resolve
return Promise.all(loaders);
}
function cycleImages (images) {
let index = 0;
setInterval(function() {
// since we need an array of the image names to preload them anyway,
// just load them via JS instead of class switching so you can cut them
// out of the CSS and save some space by not being redundant
$('body').css("background","linear-gradient(rgba(0,0,0,.3), rgba(0,0,0,.3)),url('"+images[index]+"')");
// increment, roll over to 0 if at length after increment
index = (index + 1) % images.length;
}, 28800000);
}
$(function(){
$.post('getBackgroundImages.php', { }, function(data) {
var imageCollection = JSON.parse(data);
var imageNumber = Math.floor(Math.random() * 100);
var imageLink = imageCollection.hits[imageNumber].largeImageURL;
$('body').css("background","linear-gradient(rgba(0,0,0,.3), rgba(0,0,0,.3)),url('"+imageLink+"')");
});
$.ajax('getBackgroundImages.php',{
success:function(data) {
var parsed = JSON.parse(data);
var images = parsed.hits;
var imageUrls = [];
images.forEach(function(item,index){
imageUrls.push(item.largeImageURL);
})
loadImages(imageUrls).then(cycleImages).catch(function (err) {
console.error(err);
});
}
});
});
</script>
This first puts all imageUrls into an array, then loads all images with Promise to then display then without a big delay.. I didn't really manage to get a nice transition between switching the images, as jQuerys fade-to method lets the content of the page fade out as well, rather then only the background image...
Adding more div's / changing the structure of the page is not too easy by the way, as there is a lot of floating and other css rules to make the elements appear on various positions on the page. Adding a div around all content in order to try to give that div the background-image destroyed the hole layout...
All in all, I'm confident with this solution, however, if anybody has a good idea to make the switch more smooth, feel free to tell me :)
I'm brand new to jQuery and have some experience using Prototype. In Prototype, there is a method to "flash" an element — ie. briefly highlight it in another color and have it fade back to normal so that the user's eye is drawn to it. Is there such a method in jQuery? I see fadeIn, fadeOut, and animate, but I don't see anything like "flash". Perhaps one of these three can be used with appropriate inputs?
My way is .fadein, .fadeout .fadein, .fadeout ......
$("#someElement").fadeOut(100).fadeIn(100).fadeOut(100).fadeIn(100);
function go1() { $("#demo1").fadeOut(100).fadeIn(100).fadeOut(100).fadeIn(100)}
function go2() { $('#demo2').delay(100).fadeOut().fadeIn('slow') }
#demo1,
#demo2 {
text-align: center;
font-family: Helvetica;
background: IndianRed;
height: 50px;
line-height: 50px;
width: 150px;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<button onclick="go1()">Click Me</button>
<div id='demo1'>My Element</div>
<br>
<button onclick="go2()">Click Me</button> (from comment)
<div id='demo2'>My Element</div>
You can use the jQuery Color plugin.
For example, to draw attention to all the divs on your page, you could use the following code:
$("div").stop().css("background-color", "#FFFF9C")
.animate({ backgroundColor: "#FFFFFF"}, 1500);
Edit - New and improved
The following uses the same technique as above, but it has the added benefits of:
parameterized highlight color and duration
retaining original background color, instead of assuming that it is white
being an extension of jQuery, so you can use it on any object
Extend the jQuery Object:
var notLocked = true;
$.fn.animateHighlight = function(highlightColor, duration) {
var highlightBg = highlightColor || "#FFFF9C";
var animateMs = duration || 1500;
var originalBg = this.css("backgroundColor");
if (notLocked) {
notLocked = false;
this.stop().css("background-color", highlightBg)
.animate({backgroundColor: originalBg}, animateMs);
setTimeout( function() { notLocked = true; }, animateMs);
}
};
Usage example:
$("div").animateHighlight("#dd0000", 1000);
You can use css3 animations to flash an element
.flash {
-moz-animation: flash 1s ease-out;
-moz-animation-iteration-count: 1;
-webkit-animation: flash 1s ease-out;
-webkit-animation-iteration-count: 1;
-ms-animation: flash 1s ease-out;
-ms-animation-iteration-count: 1;
}
#keyframes flash {
0% { background-color: transparent; }
50% { background-color: #fbf8b2; }
100% { background-color: transparent; }
}
#-webkit-keyframes flash {
0% { background-color: transparent; }
50% { background-color: #fbf8b2; }
100% { background-color: transparent; }
}
#-moz-keyframes flash {
0% { background-color: transparent; }
50% { background-color: #fbf8b2; }
100% { background-color: transparent; }
}
#-ms-keyframes flash {
0% { background-color: transparent; }
50% { background-color: #fbf8b2; }
100% { background-color: transparent; }
}
And you jQuery to add the class
jQuery(selector).addClass("flash");
After 5 years... (And no additional plugin needed)
This one "pulses" it to the color you want (e.g. white) by putting a div background color behind it, and then fading the object out and in again.
HTML object (e.g. button):
<div style="background: #fff;">
<input type="submit" class="element" value="Whatever" />
</div>
jQuery (vanilla, no other plugins):
$('.element').fadeTo(100, 0.3, function() { $(this).fadeTo(500, 1.0); });
element - class name
first number in fadeTo() - milliseconds for the transition
second number in fadeTo() - opacity of the object after fade/unfade
You may check this out in the lower right corner of this webpage: https://single.majlovesreg.one/v1/
Edit (willsteel) no duplicated selector by using $(this) and tweaked values to acutally perform a flash (as the OP requested).
You could use the highlight effect in jQuery UI to achieve the same, I guess.
If you're using jQueryUI, there is pulsate function in UI/Effects
$("div").click(function () {
$(this).effect("pulsate", { times:3 }, 2000);
});
http://docs.jquery.com/UI/Effects/Pulsate
$('#district').css({opacity: 0});
$('#district').animate({opacity: 1}, 700 );
Pure jQuery solution.
(no jquery-ui/animate/color needed.)
If all you want is that yellow "flash" effect without loading jquery color:
var flash = function(elements) {
var opacity = 100;
var color = "255, 255, 20" // has to be in this format since we use rgba
var interval = setInterval(function() {
opacity -= 3;
if (opacity <= 0) clearInterval(interval);
$(elements).css({background: "rgba("+color+", "+opacity/100+")"});
}, 30)
};
Above script simply does 1s yellow fadeout, perfect for letting the user know the element was was updated or something similar.
Usage:
flash($('#your-element'))
You could use this plugin (put it in a js file and use it via script-tag)
http://plugins.jquery.com/project/color
And then use something like this:
jQuery.fn.flash = function( color, duration )
{
var current = this.css( 'color' );
this.animate( { color: 'rgb(' + color + ')' }, duration / 2 );
this.animate( { color: current }, duration / 2 );
}
This adds a 'flash' method to all jQuery objects:
$( '#importantElement' ).flash( '255,0,0', 1000 );
You can extend Desheng Li's method further by allowing an iterations count to do multiple flashes like so:
// Extend jquery with flashing for elements
$.fn.flash = function(duration, iterations) {
duration = duration || 1000; // Default to 1 second
iterations = iterations || 1; // Default to 1 iteration
var iterationDuration = Math.floor(duration / iterations);
for (var i = 0; i < iterations; i++) {
this.fadeOut(iterationDuration).fadeIn(iterationDuration);
}
return this;
}
Then you can call the method with a time and number of flashes:
$("#someElementId").flash(1000, 4); // Flash 4 times over a period of 1 second
How about a really simple answer?
$('selector').fadeTo('fast',0).fadeTo('fast',1).fadeTo('fast',0).fadeTo('fast',1)
Blinks twice...that's all folks!
I can't believe this isn't on this question yet. All you gotta do:
("#someElement").show('highlight',{color: '#C8FB5E'},'fast');
This does exactly what you want it to do, is super easy, works for both show() and hide() methods.
This may be a more up-to-date answer, and is shorter, as things have been consolidated somewhat since this post. Requires jquery-ui-effect-highlight.
$("div").click(function () {
$(this).effect("highlight", {}, 3000);
});
http://docs.jquery.com/UI/Effects/Highlight
function pulse() {
$('.blink').fadeIn(300).fadeOut(500);
}
setInterval(pulse, 1000);
I was looking for a solution to this problem but without relying on jQuery UI.
This is what I came up with and it works for me (no plugins, just Javascript and jQuery);
-- Heres the working fiddle -- http://jsfiddle.net/CriddleCraddle/yYcaY/2/
Set the current CSS parameter in your CSS file as normal css, and create a new class that just handles the parameter to change i.e. background-color, and set it to '!important' to override the default behavior. like this...
.button_flash {
background-color: #8DABFF !important;
}//This is the color to change to.
Then just use the function below and pass in the DOM element as a string, an integer for the number of times you would want the flash to occur, the class you want to change to, and an integer for delay.
Note: If you pass in an even number for the 'times' variable, you will end up with the class you started with, and if you pass an odd number you will end up with the toggled class. Both are useful for different things. I use the 'i' to change the delay time, or they would all fire at the same time and the effect would be lost.
function flashIt(element, times, klass, delay){
for (var i=0; i < times; i++){
setTimeout(function(){
$(element).toggleClass(klass);
}, delay + (300 * i));
};
};
//Then run the following code with either another delay to delay the original start, or
// without another delay. I have provided both options below.
//without a start delay just call
flashIt('.info_status button', 10, 'button_flash', 500)
//with a start delay just call
setTimeout(function(){
flashIt('.info_status button', 10, 'button_flash', 500)
}, 4700);
// Just change the 4700 above to your liking for the start delay. In this case,
//I need about five seconds before the flash started.
Would a pulse effect(offline) JQuery plugin be appropriate for what you are looking for ?
You can add a duration for limiting the pulse effect in time.
As mentioned by J-P in the comments, there is now his updated pulse plugin.
See his GitHub repo. And here is a demo.
Found this many moons later but if anyone cares, it seems like this is a nice way to get something to flash permanently:
$( "#someDiv" ).hide();
setInterval(function(){
$( "#someDiv" ).fadeIn(1000).fadeOut(1000);
},0)
The following codes work for me. Define two fade-in and fade-out functions and put them in each other's callback.
var fIn = function() { $(this).fadeIn(300, fOut); };
var fOut = function() { $(this).fadeOut(300, fIn); };
$('#element').fadeOut(300, fIn);
The following controls the times of flashes:
var count = 3;
var fIn = function() { $(this).fadeIn(300, fOut); };
var fOut = function() { if (--count > 0) $(this).fadeOut(300, fIn); };
$('#element').fadeOut(300, fIn);
If including a library is overkill here is a solution that is guaranteed to work.
$('div').click(function() {
$(this).css('background-color','#FFFFCC');
setTimeout(function() { $(this).fadeOut('slow').fadeIn('slow'); } , 1000);
setTimeout(function() { $(this).css('background-color','#FFFFFF'); } , 1000);
});
Setup event trigger
Set the background color of block element
Inside setTimeout use fadeOut and fadeIn to create a little animation effect.
Inside second setTimeout reset default background color
Tested in a few browsers and it works nicely.
Like fadein / fadeout you could use animate css / delay
$(this).stop(true, true).animate({opacity: 0.1}, 100).delay(100).animate({opacity: 1}, 100).animate({opacity: 0.1}, 100).delay(100).animate({opacity: 1}, 100);
Simple and flexible
$("#someElement").fadeTo(3000, 0.3 ).fadeTo(3000, 1).fadeTo(3000, 0.3 ).fadeTo(3000, 1);
3000 is 3 seconds
From opacity 1 it is faded to 0.3, then to 1 and so on.
You can stack more of these.
Only jQuery is needed. :)
There is a workaround for the animate background bug. This gist includes an example of a simple highlight method and its use.
/* BEGIN jquery color */
(function(jQuery){jQuery.each(['backgroundColor','borderBottomColor','borderLeftColor','borderRightColor','borderTopColor','color','outlineColor'],function(i,attr){jQuery.fx.step[attr]=function(fx){if(!fx.colorInit){fx.start=getColor(fx.elem,attr);fx.end=getRGB(fx.end);fx.colorInit=true;}
fx.elem.style[attr]="rgb("+[Math.max(Math.min(parseInt((fx.pos*(fx.end[0]-fx.start[0]))+fx.start[0]),255),0),Math.max(Math.min(parseInt((fx.pos*(fx.end[1]-fx.start[1]))+fx.start[1]),255),0),Math.max(Math.min(parseInt((fx.pos*(fx.end[2]-fx.start[2]))+fx.start[2]),255),0)].join(",")+")";}});function getRGB(color){var result;if(color&&color.constructor==Array&&color.length==3)
return color;if(result=/rgb\(\s*([0-9]{1,3})\s*,\s*([0-9]{1,3})\s*,\s*([0-9]{1,3})\s*\)/.exec(color))
return[parseInt(result[1]),parseInt(result[2]),parseInt(result[3])];if(result=/rgb\(\s*([0-9]+(?:\.[0-9]+)?)\%\s*,\s*([0-9]+(?:\.[0-9]+)?)\%\s*,\s*([0-9]+(?:\.[0-9]+)?)\%\s*\)/.exec(color))
return[parseFloat(result[1])*2.55,parseFloat(result[2])*2.55,parseFloat(result[3])*2.55];if(result=/#([a-fA-F0-9]{2})([a-fA-F0-9]{2})([a-fA-F0-9]{2})/.exec(color))
return[parseInt(result[1],16),parseInt(result[2],16),parseInt(result[3],16)];if(result=/#([a-fA-F0-9])([a-fA-F0-9])([a-fA-F0-9])/.exec(color))
return[parseInt(result[1]+result[1],16),parseInt(result[2]+result[2],16),parseInt(result[3]+result[3],16)];if(result=/rgba\(0, 0, 0, 0\)/.exec(color))
return colors['transparent'];return colors[jQuery.trim(color).toLowerCase()];}
function getColor(elem,attr){var color;do{color=jQuery.curCSS(elem,attr);if(color!=''&&color!='transparent'||jQuery.nodeName(elem,"body"))
break;attr="backgroundColor";}while(elem=elem.parentNode);return getRGB(color);};var colors={aqua:[0,255,255],azure:[240,255,255],beige:[245,245,220],black:[0,0,0],blue:[0,0,255],brown:[165,42,42],cyan:[0,255,255],darkblue:[0,0,139],darkcyan:[0,139,139],darkgrey:[169,169,169],darkgreen:[0,100,0],darkkhaki:[189,183,107],darkmagenta:[139,0,139],darkolivegreen:[85,107,47],darkorange:[255,140,0],darkorchid:[153,50,204],darkred:[139,0,0],darksalmon:[233,150,122],darkviolet:[148,0,211],fuchsia:[255,0,255],gold:[255,215,0],green:[0,128,0],indigo:[75,0,130],khaki:[240,230,140],lightblue:[173,216,230],lightcyan:[224,255,255],lightgreen:[144,238,144],lightgrey:[211,211,211],lightpink:[255,182,193],lightyellow:[255,255,224],lime:[0,255,0],magenta:[255,0,255],maroon:[128,0,0],navy:[0,0,128],olive:[128,128,0],orange:[255,165,0],pink:[255,192,203],purple:[128,0,128],violet:[128,0,128],red:[255,0,0],silver:[192,192,192],white:[255,255,255],yellow:[255,255,0],transparent:[255,255,255]};})(jQuery);
/* END jquery color */
/* BEGIN highlight */
jQuery(function() {
$.fn.highlight = function(options) {
options = (options) ? options : {start_color:"#ff0",end_color:"#fff",delay:1500};
$(this).each(function() {
$(this).stop().css({"background-color":options.start_color}).animate({"background-color":options.end_color},options.delay);
});
}
});
/* END highlight */
/* BEGIN highlight example */
$(".some-elements").highlight();
/* END highlight example */
https://gist.github.com/1068231
Unfortunately the top answer requires JQuery UI. http://api.jquery.com/animate/
Here is a vanilla JQuery solution
http://jsfiddle.net/EfKBg/
JS
var flash = "<div class='flash'></div>";
$(".hello").prepend(flash);
$('.flash').show().fadeOut('slow');
CSS
.flash {
background-color: yellow;
display: none;
position: absolute;
width: 100%;
height: 100%;
}
HTML
<div class="hello">Hello World!</div>
Here's a slightly improved version of colbeerhey's solution. I added a return statement so that, in true jQuery form, we chain events after calling the animation. I've also added the arguments to clear the queue and jump to the end of an animation.
// Adds a highlight effect
$.fn.animateHighlight = function(highlightColor, duration) {
var highlightBg = highlightColor || "#FFFF9C";
var animateMs = duration || 1500;
this.stop(true,true);
var originalBg = this.css("backgroundColor");
return this.css("background-color", highlightBg).animate({backgroundColor: originalBg}, animateMs);
};
This one will pulsate an element's background color until a mouseover event is triggered
$.fn.pulseNotify = function(color, duration) {
var This = $(this);
console.log(This);
var pulseColor = color || "#337";
var pulseTime = duration || 3000;
var origBg = This.css("background-color");
var stop = false;
This.bind('mouseover.flashPulse', function() {
stop = true;
This.stop();
This.unbind('mouseover.flashPulse');
This.css('background-color', origBg);
})
function loop() {
console.log(This);
if( !stop ) {
This.animate({backgroundColor: pulseColor}, pulseTime/3, function(){
This.animate({backgroundColor: origBg}, (pulseTime/3)*2, 'easeInCirc', loop);
});
}
}
loop();
return This;
}
Put this together from all of the above - an easy solution for flashing an element and return to the original bgcolour...
$.fn.flash = function (highlightColor, duration, iterations) {
var highlightBg = highlightColor || "#FFFF9C";
var animateMs = duration || 1500;
var originalBg = this.css('backgroundColor');
var flashString = 'this';
for (var i = 0; i < iterations; i++) {
flashString = flashString + '.animate({ backgroundColor: highlightBg }, animateMs).animate({ backgroundColor: originalBg }, animateMs)';
}
eval(flashString);
}
Use like this:
$('<some element>').flash('#ffffc0', 1000, 3);
Hope this helps!
Here's a solution that uses a mix of jQuery and CSS3 animations.
http://jsfiddle.net/padfv0u9/2/
Essentially you start by changing the color to your "flash" color, and then use a CSS3 animation to let the color fade out. You need to change the transition duration in order for the initial "flash" to be faster than the fade.
$(element).removeClass("transition-duration-medium");
$(element).addClass("transition-duration-instant");
$(element).addClass("ko-flash");
setTimeout(function () {
$(element).removeClass("transition-duration-instant");
$(element).addClass("transition-duration-medium");
$(element).removeClass("ko-flash");
}, 500);
Where the CSS classes are as follows.
.ko-flash {
background-color: yellow;
}
.transition-duration-instant {
-webkit-transition-duration: 0s;
-moz-transition-duration: 0s;
-o-transition-duration: 0s;
transition-duration: 0s;
}
.transition-duration-medium {
-webkit-transition-duration: 1s;
-moz-transition-duration: 1s;
-o-transition-duration: 1s;
transition-duration: 1s;
}
just give elem.fadeOut(10).fadeIn(10);
This is generic enough that you can write whatever code you like to animate. You can even decrease the delay from 300ms to 33ms and fade colors, etc.
// Flash linked to hash.
var hash = location.hash.substr(1);
if (hash) {
hash = $("#" + hash);
var color = hash.css("color"), count = 1;
function hashFade () {
if (++count < 7) setTimeout(hashFade, 300);
hash.css("color", count % 2 ? color : "red");
}
hashFade();
}
you can use jquery Pulsate plugin to force to focus the attention on any html element with control over speed and repeatation and color.
JQuery.pulsate() * with Demos
sample initializer:
$(".pulse4").pulsate({speed:2500})
$(".CommandBox button:visible").pulsate({ color: "#f00", speed: 200, reach: 85, repeat: 15 })