This question already has answers here:
Check whether user has a Chrome extension installed
(17 answers)
Closed 5 years ago.
I want to detect if a Chrome extension is installed in user's browser. If not, I want to display a link to install the extension. If it is already installed, I want to hide the link.
This seems like a possible solution but I am confused what some_object_to_send_on_connect is supposed to be?
https://developer.chrome.com/extensions/extension#global-events
var myPort=chrome.extension.connect('jllpkdkcdjndhggodimiphkghogcpida', some_object_to_send_on_connect);
I know it's an old question, but since I managed to solve this problem (for my needs) I'd like to share.
I accomplished this by adding some info into the DOM. In extension's content.js file I have:
document.documentElement.setAttribute('extension-installed', true);
And in my page:
var isInstalled = document.documentElement.getAttribute('extension-installed');
if (isInstalled) {
...
}
I'm not sure if you want to check from a web page or from an already installed extension.
From a web page
You can't. Only Chrome Web Store can check that.
But if you write the extension and the web page, you could make your extension execute some content script in you page to confirm its installed and working.
From an extension
Provided you know the extension's id you are looking for, you can use
chrome.management.get(id, callback);
You can use chrome.management.getAll() to get a list of installed extensions, with more info than their id.
https://developer.chrome.com/extensions/management
Assuming you are the author of the extension, you can include a CustomEvent within your extension.js file, and within your site you can addEventListener to that event.
Within your extension:
const customEvent = new CustomEvent('myExtensionCheckEvent', {
detail: true // whatever value you enter here will be passed in the event
})
document.dispatchEvent(customEvent)
And your sites javascript file:
document.addEventListener('myExtensionCheckEvent', e => {
if (e.detail) {
// the extension is installed
}
})
Note that the key must be called detail.
Related
This question already has an answer here:
How to use youtube API in firefox extension?
(1 answer)
Closed 5 months ago.
i want to code a firefox extension where i can invite people to a "Yt-Music party" and it will sync up to the host YtMusic.
The element "movie_player" contains a lot of functions and variable which could be usefull, like the current time of the song.
For some reason the getCurrentTime() function works in the webconsole, but not when i have it like this, in my extension.
Do i need extra permission to do this?
Thanks in advance
const ytPlayer = document.getElementById('movie_player')
const test = ytPlayer.getCurrentTime()
console.log(test)
Extensions don't have direct access to elements on the page. You'd have to inject a content script, and then pass data (via messaging) between the page and the extension's background script (or service worker) to have this type of communication. Note also that content scripts don't get access to things like ytPlayer by default either.
Here is my code:
<script type="text/javascript"
src="http://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js">
</script>
<script>
$(function() {
var thing = [];
var bar = $.getJSON('C:\Users\cccompro\foo.json', function(obj) {
for (i = 0; i < obj.length; i++) {
thing.push(obj[i]);
}
});
});
</script>
I'm not sure why it doesn't work. "foo.json" contains an array of objects.
If you are trying the code at Question at Chrome or Chromium browsers, launch the browser instance with --allow-file-access-from-files flag set. Note that open instances of Chrome or Chromium should be closed when you launch the browser or the instance will be launched with the open browser instances' configuration folder, instead of with the flag set. You can launch Chrome or Chromium with an existing instance open and honoring the flag by using --user-data-dir flag with value set a different directory than open instance of Chrome or Chromium.
Technically, it is also possible to write to user file system without using an extension with window.webkitRequestFileSystem. Though using chrome.fileSystem within an extension provides an API designed to achieve the read/write.
See
Jquery load() only working in firefox?
Read local XML with JS
How to Write in file (user directory) using JavaScript?
How to use webkitRequestFileSystem at file: protocol
JavaScript/Ajax Write to File
Using <input type="file"> element
How to print all the txt files inside a folder using java script
You cannot read files directly from the users hard drive without the browsers permission. This would be a huge security issue if you could even though there are ways to allow this (checkout guests answer).
You could however try to make the user select the file and then read it with Javascript.
This is called the HTML 5 file API.
However, this doesn't work for any browser and you probably have to use a server anyway in this case.
For more information on this checkout this or this post.
I know this question have already been asked. BUT NONE of this,this, this,this,this or this solutions worked for me. I'm only using HTML / CSS / JS for the moment on my website. Later this should run on an apache or IIS server.
Situation :
On my website I wish user to access different servers. I got a html select with a lot of choice. Once they made their choice and click on connection button I check the choice they made and open it (it's a web interface like 127.0.0.1) in a new tab the link.
Problem : Some of the servers should not being accesssed if one is already used.
Example : If 127.0.0.1 is used by someone, no one should access 128.0.0.1 or 129.0.0.1
The solution I found was creating a file when someone access 127.0.0.1. So when someone want to access 128.0.0.1 or 129.0.0.1, I check if the file exists.
If it does exists I don't open the link and show an alert, if it does not exist I create it and open the link in new tab.
Another problem : How can I know when the tab will be closed in order to delete the file ?
Have you got another solution to this problem ?
Thx in advance for helping me, I'm just a beginner in web. No solutions worked for me so far ...
This code help you to detect when user close a tab.
<script>
window.onbeforeunload = function () {
//write your code here
return false;
};
<script>
I'm developing an extension in Chrome 4 (currently 4.0.249.0) that will show the user's StackOverflow/SuperUser/ServerFault reputation in the status bar. I've designed an options page to get the user's profile IDs and I save them to localStorage and read them well in the extension. It all works great.
The problem is I cannot find a (programmatic) way to refresh the extension upon options saving. I tried calling location.reload(); from the extension page itself upon right clicking it - to no avail. I pursued it further and tried looking at what Chrome's chrome://extensions/ page does to reload an extension, and found this code:
/**
* Handles a 'reload' button getting clicked.
*/
function handleReloadExtension(node) {
// Tell the C++ ExtensionDOMHandler to reload the extension.
chrome.send('reload', [node.extensionId]);
}
Copying this code to my event handler did not help (and yes, I tried replacing [node.extensionId] with the actual code). Can someone please assist me in doing this the right way, or pointing me at a code of an extension that does this correctly? Once done, I'll put the extension and its source up on my blog.
Now the simplest way to make extension to reload itself is to call chrome.runtime.reload(). This feature doesn't need any permissions in manifest.
To reload another extension use chrome.management.setEnabled(). It requires "permissions": [ "management" ] in manifest.
window.location.reload() works for me
I am using chromium 6.x so it might be fixed in newer version
The chrome.send function is not accessible by your extension's javascript code, pages like the newtab page, history and the extensions page use it to communicate with the C++ controller code for those pages.
You can push updates of your extension to users who have it installed, this is described here. The user's application will be updated once the autoupdate interval is hit or when they restart the browser. You cannot however reload a user's extension programmatically. I think that would be a security risk.
I just had this same problem with an extension.
Turns out you can listen for storage changes within background.js using chrome.storage.onChanged and have that perform the refresh logic.
For example:
// Perform a reload any time the user clicks "Save"
chrome.storage.onChanged.addListener(function(changes, namespace) {
chrome.storage.sync.get({
profileId: 0
}, function(items) {
// Update status bar text here
});
});
You could also reload parts of your extension this way by taking the changes parameter into account. chrome.runtime.reload() might be easier, but this has less overhead.
For all future Googlers - the Browser Extension spec now includes runtime.reload() - https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/runtime/reload
For Chrome, you might need to use chrome.runtime.reload() (but I'd handle such cases via Mozilla's awesome webextension-polyfill).
I'm working on a project and run into an issue where I need to distinguish a chrome app window from normal ones. (Specifically I'm using the --app=URL from a bash script) Because of the way things are setup, I have to have run a js script on all windows, but only do something if they are an app window. It seems that the API listed here is what I need to distinguish one window from another, but all I've managed to get are errors saying that a function or object is undefined. So how am I suppose to get the window type from the API with something like window.type?
Additionally, if you know of some other way to tell the difference between chrome windows if they are an app window or not, then that would also work. I really just need to be able to do:
if (window is app) //I don't really care how it's done
{
doSomething();
}
More information:
Tried in both Chrome and Chromium (both fully updated)
Using Ubuntu 18.04
JavaScript is running in the app window and not an extension (not developing an extension)
Can you try the following. In your console
windowType=window.location.host
It should return if you are in app window it will return as "app". Using this you can write your logic
if (windowType === 'app' ) //I don't really care how it's done
{
doSomething();
}
Hope it helps.
Doing windowType.window.location.host returned not the type of window but rather the url provided with the --app=url flag in my bash script. This means that if you open a normal window and go to the same url as provided in the app window, both would return the same url. However, since the normal window would be the same content just a different window type, the JavaScript code that I need to run on the webpage is the same, thus I would want it to run on both windows. So this solution works for me, but for anyone else who is looking for a window specific identifier, and not just a url, I suppose that is still up in the air.
(Thanks Ragavan Rajan)