I've got some js code in a chrome background extension of the following :
function handleCapture(stream) {
console.log('content captured');
console.log("backround.js stream: ", stream);
alert(stream);
// localStream = stream; // used by RTCPeerConnection addStream();
// initialize(); // start signalling and peer connection process
}
function captureCurrentTab() {
console.log('reqeusted current tab');
chrome.tabs.getSelected(null, function(tab) {
console.log('got current tab');
var selectedTabId = tab.id;
chrome.tabCapture.capture({
audio : false,
video : true
}, handleCapture);
});
}
However, when this is ran, the "handleCapture" variable "stream" that is passed in is always undefined? Is this to be expected or is there something that I am missing here?
Also, I've confirmed that my manifest.json contains the capture permission and I am using chrome canary Version 31.0.1607.1 canary Aura.
Thanks,
Mike
I had this same issue when I was trying to drive a tabCapture purely from a background script, I found this on the tabCapture reference page:
Captures the visible area of the currently active tab. This method can only be used on the currently active page after the extension has been invoked, similar to the way that activeTab works. Note that Chrome internal pages cannot be captured.
My understanding is that this means you need to drive it from a browserAction for your extension, like so:
chrome.browserAction.onClicked.addListener(function(request) {
chrome.tabs.getSelected(null, function(tab) {
chrome.tabCapture.capture({audio: true, video: true}, callback);
});
});
That's what worked for me.
You should probably provide some constraints to make it work. See:
http://developer.chrome.com/extensions/tabCapture.html#type-MediaStreamConstraint
The capture param you provided is a MediaTrackConstraint, see:
http://dev.w3.org/2011/webrtc/editor/getusermedia.html#mediastreamconstraints
that is also a simple JS object, where you should set some mandatory options, see:
http://dev.w3.org/2011/webrtc/editor/getusermedia.html#idl-def-MediaTrackConstraints
So the following should help, if you set all the needed settings in mandatory object:
chrome.tabCapture.capture({
audio : false,
video : true,
videoConstraints: {
mandatory: {
width: { min: 640 },
height: { min: 480 }
}
}
}, handleCapture);
Related
I'm writing a Chrome extension and trying to overlay a <div> over the current webpage as soon as a button is clicked in the popup.html file.
When I access the document.body.insertBefore method from within popup.html it overlays the <div> on the popup, rather than the current webpage.
Do I have to use messaging between background.html and popup.html in order to access the web page's DOM? I would like to do everything in popup.html, and to use jQuery too, if possible.
ManifestV3 service worker doesn't have any DOM/document/window.
ManifestV3/V2 extension pages (and the scripts inside) have their own DOM, document, window, and a chrome-extension:// URL (use devtools for that part of the extension to inspect it).
You need a content script to access DOM of web pages and interact with a tab's contents. Content scripts will execute in the tab as a part of that page, not as a part of the extension, so don't load your content script(s) in the extension page, use the following methods:
Method 1. Declarative
manifest.json:
"content_scripts": [{
"matches": ["*://*.example.com/*"],
"js": ["contentScript.js"]
}],
It will run once when the page loads. After that happens, use messaging but note, it can't send DOM elements, Map, Set, ArrayBuffer, classes, functions, and so on - it can only send JSON-compatible simple objects and types so you'll need to manually extract the required data and pass it as a simple array or object.
Method 2. Programmatic
ManifestV2:
Use chrome.tabs.executeScript in the extension script (like the popup or background) to inject a content script into a tab on demand.
The callback of this method receives results of the last expression in the content script so it can be used to extract data which must be JSON-compatible, see method 1 note above.
Required permissions in manifest.json:
Best case: "activeTab", suitable for a response to a user action (usually a click on the extension icon in the toolbar). Doesn't show a permission warning when installing the extension.
Usual: "*://*.example.com/" plus any other sites you want.
Worst case: "<all_urls>" or "*://*/", "http://*/", "https://*/" - when submitting into Chrome Web Store all of these put your extension in a super slow review queue because of broad host permissions.
ManifestV3 differences to the above:
Use chrome.scripting.executeScript.
Required permissions in manifest.json:
"scripting" - mandatory
"activeTab" - ideal scenario, see notes for ManifestV2 above.
If ideal scenario is impossible add the allowed sites to host_permissions in manifest.json.
Some examples of the extension popup script that use programmatic injection to add that div.
ManifestV3
Don't forget to add the permissions in manifest.json, see the other answer for more info.
Simple call:
(async () => {
const [tab] = await chrome.tabs.query({active: true, currentWindow: true});
await chrome.scripting.executeScript({
target: {tabId: tab.id},
func: inContent1,
});
})();
// executeScript runs this code inside the tab
function inContent1() {
const el = document.createElement('div');
el.style.cssText = 'position:fixed; top:0; left:0; right:0; background:red';
el.textContent = 'DIV';
document.body.appendChild(el);
}
Note: in Chrome 91 or older func: should be function:.
Calling with parameters and receiving a result
Requires Chrome 92 as it implemented args.
Example 1:
res = await chrome.scripting.executeScript({
target: {tabId: tab.id},
func: (a, b) => { return [window[a], window[b]]; },
args: ['foo', 'bar'],
});
Example 2:
(async () => {
const [tab] = await chrome.tabs.query({active: true, currentWindow: true});
let res;
try {
res = await chrome.scripting.executeScript({
target: {tabId: tab.id},
func: inContent2,
args: [{ foo: 'bar' }], // arguments must be JSON-serializable
});
} catch (e) {
console.warn(e.message || e);
return;
}
// res[0] contains results for the main page of the tab
document.body.textContent = JSON.stringify(res[0].result);
})();
// executeScript runs this code inside the tab
function inContent2(params) {
const el = document.createElement('div');
el.style.cssText = 'position:fixed; top:0; left:0; right:0; background:red';
el.textContent = params.foo;
document.body.appendChild(el);
return {
success: true,
html: document.body.innerHTML,
};
}
ManifestV2
Simple call:
// uses inContent1 from ManifestV3 example above
chrome.tabs.executeScript({ code: `(${ inContent1 })()` });
Calling with parameters and receiving a result:
// uses inContent2 from ManifestV3 example above
chrome.tabs.executeScript({
code: `(${ inContent2 })(${ JSON.stringify({ foo: 'bar' }) })`
}, ([result] = []) => {
if (!chrome.runtime.lastError) {
console.log(result); // shown in devtools of the popup window
}
});
This example uses automatic conversion of inContent function's code to string, the benefit here is that IDE can apply syntax highlight and linting. The obvious drawback is that the browser wastes time to parse the code, but usually it's less than 1 millisecond thus negligible.
I am in the process of building a Chrome extension, and for the whole thing to work the way I would like it to, I need an external JavaScript script to be able to detect if a user has my extension installed.
For example: A user installs my plugin, then goes to a website with my script on it. The website detects that my extension is installed and updates the page accordingly.
Is this possible?
Chrome now has the ability to send messages from the website to the extension.
So in the extension background.js (content.js will not work) add something like:
chrome.runtime.onMessageExternal.addListener(
function(request, sender, sendResponse) {
if (request) {
if (request.message) {
if (request.message == "version") {
sendResponse({version: 1.0});
}
}
}
return true;
});
This will then let you make a call from the website:
var hasExtension = false;
chrome.runtime.sendMessage(extensionId, { message: "version" },
function (reply) {
if (reply) {
if (reply.version) {
if (reply.version >= requiredVersion) {
hasExtension = true;
}
}
}
else {
hasExtension = false;
}
});
You can then check the hasExtension variable. The only drawback is the call is asynchronous, so you have to work around that somehow.
Edit:
As mentioned below, you'll need to add an entry to the manifest.json listing the domains that can message your addon. Eg:
"externally_connectable": {
"matches": ["*://localhost/*", "*://your.domain.com/*"]
},
2021 Update:
chrome.runtime.sendMessage will throw the following exception in console if the extension isn't installed or it's disabled.
Unchecked runtime.lastError: Could not establish connection. Receiving end does not exist
To fix this, add this validation inside the sendMessage callback
if (chrome.runtime.lastError) {
// handle error
}
I am sure there is a direct way (calling functions on your extension directly, or by using the JS classes for extensions), but an indirect method (until something better comes along):
Have your Chrome extension look for a specific DIV or other element on your page, with a very specific ID.
For example:
<div id="ExtensionCheck_JamesEggersAwesomeExtension"></div>
Do a getElementById and set the innerHTML to the version number of your extension or something. You can then read the contents of that client-side.
Again though, you should use a direct method if there is one available.
EDIT: Direct method found!!
Use the connection methods found here: https://developer.chrome.com/extensions/extension#global-events
Untested, but you should be able to do...
var myPort=chrome.extension.connect('yourextensionid_qwerqweroijwefoijwef', some_object_to_send_on_connect);
Another method is to expose a web-accessible resource, though this will allow any website to test if your extension is installed.
Suppose your extension's ID is aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa, and you add a file (say, a transparent pixel image) as test.png in your extension's files.
Then, you expose this file to the web pages with web_accessible_resources manifest key:
"web_accessible_resources": [
"test.png"
],
In your web page, you can try to load this file by its full URL (in an <img> tag, via XHR, or in any other way):
chrome-extension://aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/test.png
If the file loads, then the extension is installed. If there's an error while loading this file, then the extension is not installed.
// Code from https://groups.google.com/a/chromium.org/d/msg/chromium-extensions/8ArcsWMBaM4/2GKwVOZm1qMJ
function detectExtension(extensionId, callback) {
var img;
img = new Image();
img.src = "chrome-extension://" + extensionId + "/test.png";
img.onload = function() {
callback(true);
};
img.onerror = function() {
callback(false);
};
}
Of note: if there is an error while loading this file, said network stack error will appear in the console with no possibility to silence it. When Chromecast used this method, it caused quite a bit of controversy because of this; with the eventual very ugly solution of simply blacklisting very specific errors from Dev Tools altogether by the Chrome team.
Important note: this method will not work in Firefox WebExtensions. Web-accessible resources inherently expose the extension to fingerprinting, since the URL is predictable by knowing the ID. Firefox decided to close that hole by assigning an instance-specific random URL to web accessible resources:
The files will then be available using a URL like:
moz-extension://<random-UUID>/<path/to/resource>
This UUID is randomly generated for every browser instance and is not your extension's ID. This prevents websites from fingerprinting the extensions a user has installed.
However, while the extension can use runtime.getURL() to obtain this address, you can't hard-code it in your website.
I thought I would share my research on this.
I needed to be able to detect if a specific extension was installed for some file:/// links to work.
I came across this article here
This explained a method of getting the manifest.json of an extension.
I adjusted the code a bit and came up with:
function Ext_Detect_NotInstalled(ExtName, ExtID) {
console.log(ExtName + ' Not Installed');
if (divAnnounce.innerHTML != '')
divAnnounce.innerHTML = divAnnounce.innerHTML + "<BR>"
divAnnounce.innerHTML = divAnnounce.innerHTML + 'Page needs ' + ExtName + ' Extension -- to intall the LocalLinks extension click here';
}
function Ext_Detect_Installed(ExtName, ExtID) {
console.log(ExtName + ' Installed');
}
var Ext_Detect = function (ExtName, ExtID) {
var s = document.createElement('script');
s.onload = function () { Ext_Detect_Installed(ExtName, ExtID); };
s.onerror = function () { Ext_Detect_NotInstalled(ExtName, ExtID); };
s.src = 'chrome-extension://' + ExtID + '/manifest.json';
document.body.appendChild(s);
}
var is_chrome = navigator.userAgent.toLowerCase().indexOf('chrome') > -1;
if (is_chrome == true) {
window.onload = function () { Ext_Detect('LocalLinks', 'jllpkdkcdjndhggodimiphkghogcpida'); };
}
With this you should be able to use Ext_Detect(ExtensionName,ExtensionID) to detect the installation of any number of extensions.
Another possible solution if you own the website is to use inline installation.
if (chrome.app.isInstalled) {
// extension is installed.
}
I know this an old question but this way was introduced in Chrome 15 and so I thought Id list it for anyone only now looking for an answer.
Here is an other modern approach:
const checkExtension = (id, src, callback) => {
let e = new Image()
e.src = 'chrome-extension://'+ id +'/'+ src
e.onload = () => callback(1), e.onerror = () => callback(0)
}
// "src" must be included to "web_accessible_resources" in manifest.json
checkExtension('gighmmpiobklfepjocnamgkkbiglidom', 'icons/icon24.png', (ok) => {
console.log('AdBlock: %s', ok ? 'installed' : 'not installed')
})
checkExtension('bhlhnicpbhignbdhedgjhgdocnmhomnp', 'images/checkmark-icon.png', (ok) => {
console.log('ColorZilla: %s', ok ? 'installed' : 'not installed')
})
I used the cookie method:
In my manifest.js file I included a content script that only runs on my site:
"content_scripts": [
{
"matches": [
"*://*.mysite.co/*"
],
"js": ["js/mysite.js"],
"run_at": "document_idle"
}
],
in my js/mysite.js I have one line:
document.cookie = "extension_downloaded=True";
and in my index.html page I look for that cookie.
if (document.cookie.indexOf('extension_downloaded') != -1){
document.getElementById('install-btn').style.display = 'none';
}
You could have the extension set a cookie and have your websites JavaScript check if that cookie is present and update accordingly. This and probably most other methods mentioned here could of course be cirvumvented by the user, unless you try and have the extension create custom cookies depending on timestamps etc, and have your application analyze them server side to see if it really is a user with the extension or someone pretending to have it by modifying his cookies.
There's another method shown at this Google Groups post. In short, you could try detecting whether the extension icon loads successfully. This may be helpful if the extension you're checking for isn't your own.
Webpage interacts with extension through background script.
manifest.json:
"background": {
"scripts": ["background.js"],
"persistent": true
},
"externally_connectable": {
"matches": ["*://(domain.ext)/*"]
},
background.js:
chrome.runtime.onMessageExternal.addListener(function(msg, sender, sendResponse) {
if ((msg.action == "id") && (msg.value == id))
{
sendResponse({id : id});
}
});
page.html:
<script>
var id = "some_ext_id";
chrome.runtime.sendMessage(id, {action: "id", value : id}, function(response) {
if(response && (response.id == id)) //extension installed
{
console.log(response);
}
else //extension not installed
{
console.log("Please consider installig extension");
}
});
</script>
Your extension could interact with the website (e.g. changing variables) and your website could detect this.
But there should be a better way to do this. I wonder how Google is doing it on their extension gallery (already installed applications are marked).
Edit:
The gallery use the chrome.management.get function. Example:
chrome.management.get("mblbciejcodpealifnhfjbdlkedplodp", function(a){console.log(a);});
But you can only access the method from pages with the right permissions.
A lot of the answers here so far are Chrome only or incur an HTTP overhead penalty. The solution that we are using is a little different:
1. Add a new object to the manifest content_scripts list like so:
{
"matches": ["https://www.yoursite.com/*"],
"js": [
"install_notifier.js"
],
"run_at": "document_idle"
}
This will allow the code in install_notifier.js to run on that site (if you didn't already have permissions there).
2. Send a message to every site in the manifest key above.
Add something like this to install_notifier.js (note that this is using a closure to keep the variables from being global, but that's not strictly necessary):
// Dispatch a message to every URL that's in the manifest to say that the extension is
// installed. This allows webpages to take action based on the presence of the
// extension and its version. This is only allowed for a small whitelist of
// domains defined in the manifest.
(function () {
let currentVersion = chrome.runtime.getManifest().version;
window.postMessage({
sender: "my-extension",
message_name: "version",
message: currentVersion
}, "*");
})();
Your message could say anything, but it's useful to send the version so you know what you're dealing with. Then...
3. On your website, listen for that message.
Add this to your website somewhere:
window.addEventListener("message", function (event) {
if (event.source == window &&
event.data.sender &&
event.data.sender === "my-extension" &&
event.data.message_name &&
event.data.message_name === "version") {
console.log("Got the message");
}
});
This works in Firefox and Chrome, and doesn't incur HTTP overhead or manipulate the page.
You could also use a cross-browser method what I have used.
Uses the concept of adding a div.
in your content script (whenever the script loads, it should do this)
if ((window.location.href).includes('*myurl/urlregex*')) {
$('html').addClass('ifextension');
}
in your website you assert something like,
if (!($('html').hasClass('ifextension')){}
And throw appropriate message.
If you have control over the Chrome extension, you can try what I did:
// Inside Chrome extension
var div = document.createElement('div');
div.setAttribute('id', 'myapp-extension-installed-div');
document.getElementsByTagName('body')[0].appendChild(div);
And then:
// On web page that needs to detect extension
if ($('#myapp-extension-installed-div').length) {
}
It feels a little hacky, but I couldn't get the other methods to work, and I worry about Chrome changing its API here. It's doubtful this method will stop working any time soon.
If you're trying to detect any extension from any website,
This post helped: https://ide.hey.network/post/5c3b6c7aa7af38479accc0c7
Basically, the solution would be to simply try to get a specific file (manifest.json or an image) from the extension by specifying its path. Here's what I used. Definitely working:
const imgExists = function(_f, _cb) {
const __i = new Image();
__i.onload = function() {
if (typeof _cb === 'function') {
_cb(true);
}
}
__i.onerror = function() {
if (typeof _cb === 'function') {
_cb(false);
}
}
__i.src = _f;
__i = null;
});
try {
imgExists("chrome-extension://${CHROME_XT_ID}/xt_content/assets/logo.png", function(_test) {
console.log(_test ? 'chrome extension installed !' : 'chrome extension not installed..');
ifrm.xt_chrome = _test;
// use that information
});
} catch (e) {
console.log('ERROR', e)
}
Here is how you can detect a specific Extension installed and show a warning message.
First you need to open the manifest file of the extension by going to chrome-extension://extension_id_here_hkdppipefbchgpohn/manifest.json and look for any file name within "web_accessible_resources" section.
<div class="chromewarning" style="display:none">
<script type="text/javascript">
$.get("chrome-extension://extension_id_here_hkdppipefbchgpohn/filename_found_in_ web_accessible_resources.png").done(function () {
$(".chromewarning").show();
}).fail(function () {
// alert("failed.");
});
</script>
<p>We have detected a browser extension that conflicts with learning modules in this course.</p>
</div>
Chrome Extension Manifest v3:
const isFirefox = chrome.runtime.OnInstalledReason.CHROME_UPDATE != "chrome_update";
For FireFox, I believe chrome.runtime.OnInstalledReason.BROWSER_UPDATE will be "browser_update": https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/runtime/OnInstalledReason
I'd like to fetch some html from another domain with require.js. I know that CORS policies doesn't allow this easily. Note: I have configured the web server (with Access-Control-Allow-Origin "*" and other directives) and require.js so far that all JS and CSS files (css with require-css plugin) gets loaded from the other domain as expected - just fetching html makes problems. But in the browser network protocol I can see that the html content even gets loaded. However, this content does not get passed to the require function! The browser gets the content, but require.js doesn't provide it as an parameter...
My configuration:
requirejs.config({
baseUrl: "http://some.other.domain/",
paths: {
jquery: 'ext/jquery/jquery.min',
htmlTemplate: 'test.html?',
siteCss: '../css/site'
},
shim: {
htmlTemplate: [
'css!siteCss'
]
},
config: {
text: {
useXhr: function (url, protocol, hostname, port) {
return true;
}
}
},
map: {
'*': {
text: 'ext/require/text',
css: 'ext/require/css.min'
}
}
});
require(['text!htmlTemplate'], function (htmlTemplate) {
console.log(htmlTemplate); // prints 'undefined' into the console
});
Two notes: The useXhr configuration is taken from require.js text plugin adds “.js” to the file name but it makes no difference if it is there or not. I appended a ? to htmlTemplate path. With this the .js does not get appended to the URL and the browser loads the html content - as said before, unfortunately, without that require.js is passing it to parameter htmlTemplate.
What can I do? I've read that if I use the require.js optimizer the generated file wouldn't have this problem anymore (however that works...). But I need to develop my JS without optimization on every edit.
Update: Found one solution but I'd be happy if anyone can provide the 'right' solution.
I've found the actual problem! This part:
config: {
text: {
useXhr: function (url, protocol, hostname, port) {
return true;
}
}
},
should really do it. However, I found out that it wasn't called at all. Instead, the default implementation was called. And this returned false.
To make it work it is necessary to have the right keys in the config section since the mapping doesn't seem to be evaluated for it.
So this is the right configuration that fetches HTML from the other domain:
requirejs.config({
baseUrl: "http://some.other.domain/",
paths: {
jquery: 'ext/jquery/jquery.min',
htmlTemplate: 'test.html', // // ---> removed the '?'
siteCss: '../css/site'
},
shim: {
htmlTemplate: [
'css!siteCss'
]
},
config: {
'ext/require/text': { // ---> full path is required!!!
useXhr: function (url, protocol, hostname, port) {
return true;
}
}
},
map: {
'*': {
text: 'ext/require/text',
css: 'ext/require/css.min'
}
}
});
require(['text!htmlTemplate'], function (htmlTemplate) {
console.log(htmlTemplate); // now prints HTML into the console!!!
});
Hallelujah!
Found the right hint here. Another option might be to set the path for text. At least the configuration must be set somehow so that the function gets called...
I think I've found a solution. Doc of requirejs/text:
So if the text plugin determines that the request for the resource is on another domain, it will try to access a ".js" version of the resource by using a script tag. Script tag GET requests are allowed across domains. The .js version of the resource should just be a script with a define() call in it that returns a string for the module value.
Because of that I changed the configuration to this, so text is not used anymore:
requirejs.config({
baseUrl: "http://some.other.domain/",
paths: {
jquery: 'ext/jquery/jquery.min',
htmlTemplate: 'test.html', // removed the '?'
siteCss: '../css/site'
},
shim: {
htmlTemplate: [
'css!siteCss'
]
},
map: {
'*': {
// removed the text plugin
css: 'ext/require/css.min'
}
}
// removed the useXhr configuration for the text plugin
});
require(['htmlTemplate'], function (htmlTemplate) {
console.log(htmlTemplate); // prints '<div>Here I am!</div>' into the console
});
Now http://some.other.domain/test.html.js gets loaded. The content of test.html is:
define(function () {
return '<div>Here I am!</div>';
});
So I surrounded the HTML with a little bit of JS - no problem to me. And now htmlTemplate is set to the expected string. It's not pure HTML anymore, but since it is a fixed template (i.e. not generated) it may be acceptable.
I am getting No 'Access-Control-Allow-Origin' header is present on the requested resource. after adding the code
config: {
'ext/require/text': { // required!!!
useXhr: function (url, protocol, hostname, port) {
return true;
}
}
},
Hi!
I'm building a Chrome extension, in which I need to embed a SWFobject in the background page.
Everything works, except the JavaScript controls for the SWFobject and the eventListeners.
My guess is that it has something to do with the cross-domain policies, because while testing the page on a webserver everything worked fine.
Anyway, here's a snippet:
In the main page:
var playerView = chrome.extension.getBackgroundPage();
$('#playerPause').click(function(){
playerView.playerPause();
});
In the background:
function playerPause() {
if (postData[nowPlaying].provider == 'youtube' ) {
player.pauseVideo();
}
else if (postData[nowPlaying].provider == 'soundcloud' ) {
player.api_pause();
};
}
And the eventListeners:
soundcloud.addEventListener('onMediaEnd', playerNext);
function onYouTubePlayerReady(player) {
player.addEventListener("onStateChange", "function(state){ if(state == 0) { playerNext(); } }");
}
In the console it throws
"Uncaught TypeError: Object # has no method
'pauseVideo'"
for both the Youtube embed the Soundcloud one.
Also, the SWFobject is embedded like this (and works):
function loadTrack (id) {
if(postData[id].provider == 'youtube') {
swfobject.embedSWF(
"http://www.youtube.com/e/" + postData[id].url + "?enablejsapi=1&playerapiid=player",
"player",
"1",
"1",
"8",
null,
{
autoplay: 1
},
{
allowScriptAccess: "always"
},
{
id: "player"
}
);
}
else if(postData[id].provider == 'soundcloud') {
swfobject.embedSWF(
'http://player.soundcloud.com/player.swf',
'player',
'1',
'1',
'9.0.0',
'expressInstall.swf',
{
enable_api: true,
object_id: 'player',
url: postData[id].url,
auto_play: true
},
{
allowscriptaccess: 'always'
},
{
id: 'player',
name: 'player'
}
);
}
}
Sorry for the lengthy post, I wanted to provide as much information as possible.
Also, I know the code isn't pretty, this was only my second application ;)
Thanks a lot in advance to anyone who can help,
Giacomo
You can have a look at this extension, you can not access local connection in chrome extension, but you can run a content script as a proxy script instead.(You can serve a proxy page on gae or any other free servers)
The problem here is that you can't use inline scripts or inline event handlers in chrome extensions ever since the manifest evolved to v2.
You should have added the manifest file for me to understand what's going on better. But briefly all you CAN ever do is
In the main page,
Remove all inline scripts and move them to an external JS file.
Remove inline event listeners, move them to the same or another external JS and use
addEventListener().
But the issue is, You can't execute calls to the swf in the background page or expect it to return anything. All these will continue to give you "Uncaught TypeError" Exception.
Take the case of a webcam image capturing swf, the webcam will be streamed to the page, but the function call to it can never be made and hence the image will never be captured.
My project to scan QR codes from the addons popup met the ruins due to this.
I am new to Chrome extension. I have a question about how to make the extension to open a "Help" page automatically after installation. Currently, I am able to check whether the extension is running the first time or not by saving a value into localStorage. But this checking is only carried out when using click the icon on the tool bar. Just wondering if there is a way that likes FF extension which uses the javascript in to open a help page after the installation. Thanks.
Edit:
Thanks for the answer from davgothic. I have solved this problem.
I have another question about the popup. My extension checks the url of current tab,
if OK(url){
//open a tab and do something
}
else{
//display popup
}
Is it possible to show the popup in this way?
Check this updated and most reliable solution provided by Chrome: chrome.runtime Event
chrome.runtime.onInstalled.addListener(function (object) {
let externalUrl = "http://yoursite.com/";
let internalUrl = chrome.runtime.getURL("views/onboarding.html");
if (object.reason === chrome.runtime.OnInstalledReason.INSTALL) {
chrome.tabs.create({ url: externalUrl }, function (tab) {
console.log("New tab launched with http://yoursite.com/");
});
}
});
Add this to your background.js I mean the the page you defined on manifest like following,
....
"background": {
"scripts": ["background.js"],
"persistent": false
}
...
UPDATE: This method is no longer recommended. Please see Nuhil's more recent answer below.
I believe what you need to do is put something like this into a script in the <head> section of your extension's background page, e.g. background.html
function install_notice() {
if (localStorage.getItem('install_time'))
return;
var now = new Date().getTime();
localStorage.setItem('install_time', now);
chrome.tabs.create({url: "installed.html"});
}
install_notice();
As of now (Aug 2022) the right way to execute code on first install or update of an extension using Manifest V3 is by using the runtime.onInstalled event.
This event is documented here: https://developer.chrome.com/extensions/runtime#event-onInstalled
There is one example for this exact case in the docs now:
https://developer.chrome.com/docs/extensions/reference/tabs/#opening-an-extension-page-in-a-new-tab
Note: This example above is wrong as the callback function parameter is Object with the key reason and not reason directly.
And another example here (this one is correct but does not open a tab):
https://developer.chrome.com/docs/extensions/reference/runtime/#example-uninstall-url
chrome.runtime.onInstalled.addListener((details) => {
if (details.reason === chrome.runtime.OnInstalledReason.INSTALL) {
// Code to be executed on first install
// eg. open a tab with a url
chrome.tabs.create({
url: "https://google.com"
});
} else if (details.reason === chrome.runtime.OnInstalledReason.UPDATE) {
// When extension is updated
} else if (details.reason === chrome.runtime.OnInstalledReason.CHROME_UPDATE) {
// When browser is updated
} else if (details.reason === chrome.runtime.OnInstalledReason.SHARED_MODULE_UPDATE) {
// When a shared module is updated
}
});
This code can be added to a background service worker: https://developer.chrome.com/docs/extensions/mv3/migrating_to_service_workers/
It would be better to place a "version" number so you can know when an extension is updated or installed.
It has been answered here:
Detect Chrome extension first run / update
All you need to do is adding the snippet below to your background.js file
chrome.runtime.onInstalled.addListener(function (object) {
chrome.tabs.create({url: `chrome-extension://${chrome.runtime.id}/options.html`}, function (tab) {
console.log("options page opened");
});
});