I'd like to know if with HTML5 and JavaScript - and relative support in later browser versions, plus some server side technology PHP could I manage a dynamic video playlist.
I would like to play video1, video2, video3 (placed in a web server sub directory) and loop. I would like to then add a video (video4) and then system should play video1, video2, video3, video4 (loop).
With PHP I can easy add file video4 in sub directory but I don't know about a playlist loop in HTML5/ECMA/JavaScript.
It it possible and easy to implement?
Thank in advance.
This would be relatively easy to set up.
On the PHP side you would do the detection of what's in your subdirectory and based on that output the HTML so it's all in your page.
You could then start that HTML5 video with JQuery and use a callback to start the next one. If the callback is the final one then you start over again.
Relevant code samples:
In PHP get the files in the subdirectory with:
$dir = '/subdirectory';
$videoFileNames = scandir($dir);
// $videoFilesNames[0-...] is now the file names you can use to create the HTML
In JQuery you can start the video with:
$('#videoId').get(0).play();
Catch the callback with:
$("#videoId").bind("ended", function() {
// ...
});
You can create an xml form that lists all the video sources and set title and such there, then call it in your HTML. If you dont' know how to do this I can send over what mine looks like.
Related
I have a system that was built in JavaScript for a website ages ago which I need to make slight changes for; which includes saving the data to be loaded again later.
The main difference is this time the system will be completely local; no server whatsoever.
What is the best way to save/update (& load) a file in locally; ideally without a download prompt.
You're looking for [localStorage][1].
What you can do with localStorage is retrieve the image as Base64 in localStorage and then when page is loaded you can access to localStorageto get the image and put in your img tag.
Here's is working fiddle : http://jsfiddle.net/joherro3/Gg6AG/506/
Im using a array to display some images in a website:
var paintingImages;
paintingImages =
[
{
url: 'images/objects/ron.jpg',
alt: 'ron'
}
];
This js code is written in paintings.js and my main js code is written in the file main.js
I have made this website for a artist and I want to give him the opportunity to login and add pictures to his website. I'm not that good with php, but adding images to a ftp in a folder is no problem.
Because I'm using a array for retrieving the images, I need to be able to add items to the array.
This is the part where I'm stuck. I don't know how to edit a existing js file, so the next time I open the website, the items (images) will been shown.
Activexobject is not a option because it's only possible in IE.
In summary:
I need to add a item to a array
I need to save this into the file, so the next time the website opens, it will be shown
I'm not verry good with php, I prefer javascript
Can't use Activexobject because of the use of multiple browsers
You can not simply modify a javascript file sitting on the server from browser side javascript.
You need to implement some server side logic.
If you don't like PHP, but like JavaScript, check out NodeJS for example.
With Node you should be able to build some lightweight serverside logic to modify your json array file with additional images.
You would need to change your logic .. You need to send this data to server anyhow . and when you load your next time take it back from server and update your webpage accordingly. I would suggest use any javascript MVC framework like backbone, angular.js. it will help you.
Use a database.
Save it to a database server (You figure this out, could be via forms, xhr, websockets, etc.).
On page load, load the correct data for the current user.
Create the $userPaintings array (call it what you want) from the user data in PHP.
Then simply output a JS object in the page with PHP:
<script>
var paintingImages = <?php json_encode($userPaintings); ?>
</script>
I am making a browser based audio player. So for making a playlist from the local directory I am using :
<input type="file" id="getFile" />
Then I am using a button to confirm the playlist.On clicking the button I am calling a javascript function to change the src of the audio tag to play the new audio file selected in the playlist. I want the exact path of the file from the input file to run in the HTML5 audio player but it starts taking the path as C://Fakepath/filename.mp3. Can someone help me with this.
This is a security feature, by design. You should not be able to read the original file path of a file input into a browser form. File input is for reading file contents only, not metadata like path on the user's file system.
The good news is that you don't need the original file path. You can use FileReader's readAsDataURL to convert the file contents into a base64-encoded data URL and use that as the audio src. To read from #myUploadInput and output through #myAudioElement (also available as a working fiddle):
var reader = new FileReader();
reader.onload = function (event) {
document.getElementById("myAudioElement").src = event.target.result;
};
reader.readAsDataURL(document.getElementById("myUploadInput").files[0]);
if the user is 'building' / creating the playlist based on files they have locally you could do a 'browse' field (s) where they select the local audio files, then take the contents of the field (that Should include the paths to those images), build an array of the count/id, filename.mp3, and path... then, based on what is 'chosen' to play, just reassemble the full local path and play that file.
that would be an approach I would take anyway to see if it would work. the necessary piece here is getting the user to disclose the paths to the audio files... but Im still not 100% sure it would work given the security feature that the earlier commenter posted a link to.
if this were included in an application the user approved for local installation you could just refer to it using the 'application directory' and copy the file to that 'safe location' but since its web based it just really opens up a whole can of worms in terms of a potentially unapproved / authorized web function knowing your local directory structure. good luck, let me know if you find a solution.
I'm working on an offline only help system which requires loading a large amount of search-related data into an iframe before the search functionality can be used. Due to the folder structure of the project, I am unable to use Ajax-related background load methods, since the files I need are loaded a few directories "up and over."
I have written some code which delays the loading of the help data until the rest of the webpage is loaded. The help data consists of a bunch of javascript files which have information about the terms, ect that exist in the help books which are installed on the system.
The webpage works fine, until I start to load this help data into a hidden iframe. While the javascript files are loading, I can not use any of the webpage. Links that require a small files be downloaded for hover over effects don't show up, javascript (switching tabs on the page) has no effect.
I'm wondering if this is just a limitation of the way javascript works, or if there's something else going on here. Once all the files are loaded for the help system, the webpage works as expected.
function test(){
var MGCFrame = eval("parent.parent");
if((ALLFRAMESLOADED == true)){
t2 = MGCFrame.setTimeout("this.IHHeader.frames[0].loadData()",1);
}
else{
t1 = MGCFrame.setTimeout("this.IHHeader.frames[0].test()",1000);
}
}
Load data simply starts the data loading process.
Thanks for any help you can provide.
I was loading quite a few javascript files--- around 200 or so. I minimized the delay by combining some files, and using jquery's getScript function for the others. To help the browser not lock up while loading all these files, I populated a global array with a list of the files which needed to be downloaded, and then recursively called a helper function which waited 100ms, then called getScript, then called itself. This helped background load the files without making the browser unusable.
I have the following problem which I'm trying to solve with javascript. I have a div with a background image specified in a css file, and I want my javascript to change that image periodically (let`s say every 5 secs).
I know how to do that, the problem is that I have a folder of images to choose from for the back image. I need to be able to read the filenames (from the image folder) into an array, change the background image of the div, delay for 5 seconds and change again.
in your javascript, use an array like
var images = [ "image1.jpg", "image2.jpg", "image3.jpg" ];
function changeImage() {
var image = document.getElementById("yourimage");
image.src=$images[changeImage.imageNumber];
changeImage.imageNumber = ++changeImage.imageNumber % images.length;
}
changeImage.imageNumber=0;
setInterval(changeImage,5000);
The values in the array should be generated by your php
You're still going to need php or asp to query the folder for files. Javascript will not be able to "remotely" inspect the file system.
You can do something like the following in jQuery:
$.ajax({
url: 'getFolderAsArrayOfNames.php',
dataType: 'json',
success: function(data) {
for(var i=0;i<data.length;i++) {
// do what you need to do
}
});
});
And in your getFolderAsArrayOfNames.php, something like this:
echo "function "
.$_GET['callback']
."() {return "
.json_encode(scandir('somepath/*.jpg'))
."}";
If you are using Apache as your
web server, and
if you can configure
it to provide a default directory
listing for your images folder (use
the appropriate options in
httpd.conf and/or .htaccess), and
if you don't care that the list of
images is available to everyone who
visits your web site,
then you don't need PHP or any other server-side processing.
You can use XMLHttpRequest (or the jQuery ajax function, which is a nice wrapper) to get the listing for the folder. The response will be HTML and it will look something like this:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<html>
<head>
<title>Index of /demo1/images</title>
</head>
<body>
<h1>Index of /demo1/images</h1>
<pre><img src="/icons/blank.gif" alt="Icon "> Name Last modified Size Description<hr><img src="/icons/back.gif" alt="[DIR]"> Parent Directory -
<img src="/icons/image2.gif" alt="[IMG]"> tree.gif 17-Mar-2009 12:58 6.2K
<img src="/icons/image2.gif" alt="[IMG]"> house.gif 17-Mar-2009 12:58 6.5K
<img src="/icons/image2.gif" alt="[IMG]"> car.gif 02-Mar-2009 15:37 8.4K
<img src="/icons/image2.gif" alt="[IMG]"> elephant.jpg 02-Mar-2009 15:37 3.4K
<hr></pre>
<address>Apache/2.0.63 (Unix) Server at zeppo Port 80</address>
</body></html>
Since this output is pretty predictable, you might try parsing out the filenames using a JavaScript regular expression, but it's probably just as easy and more robust to create a hidden DIV on your page, put the HTML response into that DIV, and then use DOM methods to find <a href>s that are after <img> tags with an alt="[IMG]" attribute. Once again, using jQuery Selectors or similar helper methods available in other toolkits will make this DOM parsing pretty easy.
Once you have the URL of the new image (parsed from the href), you can set the new CSS background for your div with the .style.backgroundImage property.
You cannot do any file IO using JavaScript mainly because of security reason, so anyway you have to create some back end service which will update you with an list of available files in your folder. You don't have to do it in a hard way, you can use AJAX to it smoothly and nicely
You can't read a folder's contents, neither on the server nor on the clientside.
What you can do is to read the folder's contents with the help of a serverside script, and load it to a JavaScript array while processing the page.
This would not be ideal but in the absence of server-side processing (which you really should be doing--either PHP or Rails or Perl or whatever your host supports), you could allow directory listing on your images folder. This has security implications.
Then loading e.g., http://mysite.com/rotatingImages should respond with a list of files. You could do this with AJAX, parse out the relevant hrefs, push them onto an array and render your rotating images in JS.
You must send the list of names along with the JavaScript and then iterate through it.
A noted above, you can not access server's system from a client's browser (which is where JavaScript runs).
You have 3 possible solutions:
Create the JavaScript file via some dynamic back-end (php or perl scripts are best for that).
The main JavaScript function could still be static but the initialization of the array used by it (either as a snippet on the main HTML page or a separate .js imported file) would be a php/perl generated URL.
A recent StackOverflow discussion of the topic is at link text
Make an XMLHttpRequest (AJAX) call from your JavaScript to a separate service (basically a URL backed by - again - php/perl backend script) returning XML/JSON/your_data_format_of_choice list of files.
This is probably a better solution if you expect/want/need to refresh a frequently-changing list of images, whereas a pre-built list of files in solution #1 is better suited when you don't care about list of files changing while the web page is loaded into the browser.
An un-orthodox solution - if browsers you care about support animated background images (gif/png), just compile your set of images, especially if they are small sized, into an animated gif/png and use that as background.