get name of files in a folder with javascript - javascript

I have a background image folder that there is some picture that i want to use them for background.
how i can get their names and put them on array whit javascript?if i cant they do with javascript,how can i do that?
i want to read name of files and use javacsript and link for change background image whit css.
<script>
function nextbg(){
$('#bg').css('background-image','url(Images/bg2.jpg)');
}
</script>

This solution is created according to the fact that browser dont have access to folders/filesystem.
Javascript can not access the filesystem. This has to be done by a server script and then be feed to the javascript.
I had the simliar problem when building my game engine when I was loading all my diffrent tiles. I ended up doing it like this.
This solution do pose two a problems when implementing it.
You will have to define the amout of images in the "NrofTiles" array
The images must be named like tile1, tile2 ... tile9 so you can
increment the path to them.
The typeOfTiles[typeCounter] is just there to give me access to different folders, in my case for my tiles, grass, houses, water and so on.
for(var i = 0; i <= nrofTiles.length; i++)
{
for(var x = 0; x <= nrofTiles[i]; x++)
{
console.log
("Fetching tile "+(x + 1 )+" of " + 14);
img = new Image();
//My path
img.src = 'Images/Cart/' + typeOfTiles[typeCounter] + '/' + (x + 1) + '.png';
imgArray.push(img);
var intervalFunctionen = function () {
alert("calls back here");
};
}//end for loop!
}end outer for loop!
When everything is loaded(the tiles), you do this to change the background picture.
This is an example of a changing body background. You could make a link with an ID lets say "iamthelink".
HTML
Change BG
JAVASCRIPT
var link = document.getElementsById('iamthelink');
link.onclick= function() {
var body = document.getElementsByTagName('body')[0];
body.style.backgroundImage = 'url(http://localhost/background.png)';
}

Related

How to make an image play sound onclick using JavaScript?

So I want to create my 1st project using JS HTLM and CSS, which will be like a drum website ...
when I click on an image it should make sound . So, All I know is making a button make sound by clicking on it not an actual image. If you have any idea what should I put in this YYY place ?
here's my JS file code :
PS : soundi is this image's class
var soundi = document.querySelectorAll(".soundi").length;
for (var i = 0; i < soundi ; i++) {
document.querySelectorAll(".soundi")[i].addEventListener("click", function () {
var clickDe = this.YYYY;
switch (clickDe) {
case "YYYY" :
var tom1 = new Audio('sounds/tom-1.mp3');
tom1.play();
break;
}
})
}
You could add an Id to each image and then register the event listeners like so:
function imageClicked(event) {
const imgId = event.target.id; // imgId is the name of the instrument => the name of the sound file without the extension
const soundFile = new Audio(`sounds/${imgId}.mp3`); // this way, you don't have to use a switch statement which can get very long and chaotic
soundFile.play();
}
document
.querySelectorAll(".soundi") // querySelectorAll returns all the images so no need to put it in a for loop
.forEach((img) => img.addEventListener("click", imageClicked));
You will obviously have to choose the image ids properly so that they match up with the file names.

Dynamically change image in javascript

JavaScript Noob here.
I want to show the dynamically changing image effect like this:
http://dotsignals.org/google_popup.php?cid=202
(if this webpage cannot show changing image, click on any camera at http://dotsignals.org)
I have examined the code, and have some questions:
1.The website uses setImage and refreshSetImage to initialize and refresh the image for a dynamically changing effect. What is the use of Math.random in here? I understand it is a way to differentiate images from different time at the same cam. But how does it works? How would the backend respond?
2.Related to the first question. What is the mechanism of the refreshSetImage? I didn't see any sign of requesting data from the server. Does it send a "GET"? How does it refresh the image?
function setImage(imageID){
var currentImage = imageID;
document.getElementById(currentImage).src ='http://207.251.86.238/cctv9.jpg'+'?math=';
refreshSetImage();
}
function refreshSetImage() {
document.images["myCam"].src = 'http://207.251.86.238/cctv9.jpg'+'?math='+Math.random();
setTimeout('refreshSetImage()',1000);
}
function ScaleSize(imageID) {
var elem = document.getElementById(imageID);
elem.style.width = 500;
elem.style.height = 300;
}
3.How is the backend designed?
4.Now I want to use these two functions in my own project. I want to add a parameter of camID in the setImage and refreshSetImage functions, so the src of the image will change to something like: 'http://..../'+camID+'.jpg'+'?math'. camID is a String that identifies different cameras. I changed it to:
function refreshSetImage(camID) {
document.images["myCam"].src = 'http://207.251.86.238/'+camID+'.jpg'+'?math='+Math.random();
setTimeout('refreshSetImage(camID)',1000);
}
function setImage(imageID,camID){
var currentImage = imageID;
document.getElementById(currentImage).src = 'http://207.251.86.238/'+camID+'.jpg'+'?math=';
refreshSetImage(camID);
}
and got an error :Uncaught ReferenceError: camID is not defined VM132:1. The image is not changing as well. I don't know what is the problem. What is VM132:1 ?
Thanks
check
function refreshSetImage(imageID,camID) {
currentImage = imageID;
url = 'http://207.251.86.238/'+camID+'.jpg'+'?math='+Math.random();
//document.getElementById(currentImage).src= url;
console.log(url);
}
$(document).ready(function(){
imageID = "imageID";
camID = "camID";
setInterval(function() {
refreshSetImage("imageID","camID");
}, 3000);
});
https://jsfiddle.net/Cuchu/vr1ftwg1/

Loop through all images and change size?

The script below works for posts that are already on the page. But, when I click on load more posts, the new posts that get added to the page don't change the source of the image so that they are blurry.
Is there a way to loop through all images and change the src of it, even the ones that are not shown?
function resizeThumb(size) {
var popularPost = document.getElementById('Blog1');
var image = popularPost.getElementsByTagName('img');
for (var i = 0; i < image.length; i++) {
image[i].src = image[i].src.replace(/\/s72\-c/g, "\/s" + size + "-c");
image[i].width = size;
image[i].height = size;
}
}
// Resize to 200 × 200
resizeThumb(200);
Yes. Basically locate the button that loads more, find it's name.
If your button looks like this:
Load more
Put this before it so it looks like this:
<span onclick="resizeThumb(200); ">
Load more
</span>
It's the lousiest solution but the question is lousy too.

Showing random divs images every time page is load

Lets say I have these images gallery, how do i randomly display the images everytime when i reload the page?
http://creativepreviews.com/fiddle/study/20131007/
Let's say the image will display in the background of the DIV, then the following should do it.
// JS
var imgArray = ["img1.jpg", "cat.jpg", "sky.jpg"]
function randomBg() {
x = Math.random()
y = Math.round(x * 10)
if (imgArray[y] != undefined) {
document.getElementById("blah").style.backgroundImage = "url('" + imgArray[y] + "')"
} else {
document.getElementById("blah").style.backgroundImage = "url('default.jpg')"
}
}
...and the HTML.
<script src="test.js"></script>
<body onload="randomBg()">
<div id="blah"></div>
...or you could replace the style.backgroundImage in the JS with innerHTML = <img src=" etc...
You could do something along these lines (not tested)
var grd = $('#grid');
var imgs = grd.children();
imgs.sort(function(){return (Math.round(Math.random()) - 0.5);});
grd.remove('li');
for(var i=0;i < imgs.length;i++) grd.append(imgs[i]);
In essence what we are doing is getting all the li elements in 'grid' into an array, randomizing them, removing them all from 'grid' and then putting them back in again.
If you had supplied a working fiddle rather than a link to the finished article it would be easier to modify it and provide a more complete solution.

Getting images to change in a for loop in javascript

So far I created an array with 11 images, initialized the counter, created a function, created a for loop but here is where I get lost. I looked at examples and tutorial on the internet and I can see the code is seeming simple but I'm not getting something basic here. I don't actually understand how to call the index for the images. Any suggestions. Here is the code.
<script type="text/javascript">
var hammer=new Array("jackhammer0.gif",
"jackhammer1.gif",
"jackhammer2.gif",
"jackhammer3.gif",
"jackhammer4.gif",
"jackhammer5.gif",
"jackhammer6.gif",
"jackhammer7.gif",
"jackhammer8.gif",
"jackhammer9.gif",
"jackhammer10.gif")
var curHammer=0;
var numImg = 11;
function getHammer() {
for (i = 0; i < hammer.length; i++)
{
if (curHammer < hammer.length - 1) {
curHammer = curHammer +1;
hammer[i] = new Image();
hammer[i].src="poses/jackhammer" +(i+1) + ".gif";
var nextHammer = curHammer + 1;
nextHammer=0;
{
}
}
}
}
setTimeout("getHammer()", 5000);
</script>
</head>
<body onload = "getHammer()";>
<img id="jack" name="jack" src = "poses/jackhammer0.gif" width= "100" height ="113" alt = "Man and Jackhammer" /><br/>
<button id="jack" name="jack" onclick="getHammer()">Press button</button>
Following on what Paul, said, here's an example of what should work:
var hammer=["jackhammer0.gif","jackhammer1.gif","jackhammer2.gif","jackhammer3.gif",
"jackhammer4.gif","jackhammer5.gif","jackhammer6.gif","jackhammer7.gif",
"jackhammer8.gif","jackhammer9.gif","jackhammer10.gif"];
var curHammer=0;
function getHammer() {
if (curHammer < hammer.length) {
document.getElementById("jack").src= "poses/" + hammer[curHammer];
curHammer = curHammer + 1;
}
}
setTimeout("getHammer()", 5000);
The big missing element is that you need to call getElementById("jack") to get a reference to the DOM Image so that you can change it's source. If you're using jQuery or most other JS frameworks, just type $("#jack") to accomplish the same.
I don't understand the need for the for loop at all, just increment the index value [curHammer] each time you click, and reset if it passes your max index length (in this case 11).
Pseudo-Code:
currentHammer = -1
hammers = [ "a1.jpg", "a2.jpg", "a3.jpg"]
getHammer()
{
currentHammer = currentHammer + 1;
if(currentHammer > 2)
currentHammer = 0;
image.src = hammers[currentHammer];
}
a) are you just trying to show an animated gif? If so, why not use Adobe's Fireworks and merge all those gifs into a single gif?
b) you know that the way you have it the display is going to go crazy overwriting the gif in a circle right?
c) you might want to put a delay (or not). If so, make the load new gif a separate function and set a timeout to it (or an interval).
Also, you are being redundant. How about just changing the src for the image being displayed?:
var jackHammer = new Array();
for (var i=0;i<11;i++) { //pre-loading the images
jackHammer[i] = new image();
jackHammer[i].src = '/poses/jackHammer'+i.toString()+'.gif';
} //remember that "poses" without the "/" will only work if that folder is under the current called page.
for (var i=0;i<11;i++) { //updating the image on
document.getElementById('jhPoses').src = jackHammer[i].src;
}
on the document itself,
< img id='jhPoses' src='1-pixel-transparent.gif' width='x' height='y' alt='poses' border='0' />

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