I want my Chrome Extension to load Javascript once user visits a website. But currently, the Javascript is executed only when user click the extension icon and till the extension popup is open.
I saw the answer in this Chrome extension to load the script without clicking on icon question.
My manifest.json is:
{
"manifest_version": 2,
"name": "Javascript example",
"description": "Some description.",
"version": "1.1",
"browser_action": {
"default_icon": "icon.png",
"default_popup": "popup.html"
},
"permissions": [
"activeTab",
"storage"
],
"content_scripts": [
{
"matches": ["*://*/*"],
"js": ["popup.js"]
}
]
}
The popup.js is:
document.addEventListener('DOMContentLoaded', () => {
alert("Working");
});
popup.html is:
<!doctype html>
<html>
<head>
<title>Getting Started Extension's Popup</title>
<script src="popup.js"></script>
</head>
<body>
</body>
</html>
The alert dialog is shown only when I click the extension icon (i.e. when popup.html is run), not when a page loads. I want the popup.js file to execute without user needing to click the extension icon. What am I missing?
Your manifest works, but run_at defaults to document_idle which means that DOMContentLoaded has already fired. This can be fixed by specifying run_at to document_start instead.
{
"manifest_version": 2,
"name": "Javascript example",
"description": "Some description.",
"version": "1.1",
"browser_action": {
"default_icon": "icon.png",
"default_popup": "popup.html"
},
"permissions": [
"activeTab",
"storage"
],
"content_scripts": [
{
"matches": ["*://*/*"],
"run_at": "document_start",
"js": ["popup.js"]
}
]
}
Source: https://developer.chrome.com/extensions/content_scripts
You need the content script.
Content scripts are JavaScript files that run in the context of web
pages. By using the standard Document Object Model (DOM), they can
read details of the web pages the browser visits, or make changes to
them.
Here are some examples of what content scripts can do:
Find unlinked URLs in web pages and convert them into hyperlinks
Increase the font size to make text more legible
Find and process microformat data in the DOM
If your content script's code should always be injected, register it in the extension manifest using the content_scripts field, as in the following example.
{
"name": "My extension",
...
"content_scripts": [
{
"matches": ["http://www.google.com/*"],
"css": ["mystyles.css"],
"js": ["jquery.js", "myscript.js"]
}
],
...
}
Refer this link for more information & implementation.
You can use content script that runs in the context of the page and this way you'll know when the user visits a specific site: https://developer.chrome.com/extensions/content_scripts
Related
I am trying to run some JS code in a html file located in my extension's directory chrome-extension://<my_extension_id>/notice.html
I have tried using content scripts to inject the JS, 1st I tried the programmatically route by using chrome.tabs.executeScript. After that didn't work I tried to use the manifest to do it which also failed .
manifest.json:
{
"name": "Shield",
"version": "0.0.1",
"manifest_version": 2,
"description": "Shield",
"homepage_url": "https://example.com",
"browser_action": {
"default_popup": "popup.html"
},
"background": {
"scripts": ["background.js"],
"persistent": false
},
"permissions": [
"tabs",
"activeTab"
]
}
notice.html:
<html>
<head>
<title>this page</title>
</head>
<body>
<h1>test page!!!</h1>
<p id="ref_test"></p>
</body>
</html>
notice.js:
alert("notice js injected");
I would like to run the content script or some how run JS (notice.js) on the url chrome-extension://<my_extension_id>/notice.html, However it normally just does not inject
Directories
----MyExtension
|----popup.html
|----popup.js
|----content.js
|----background.js
|----manifest.json
mainfest.json
{
"manifest_version": 2,
...........
"content_scripts": [
{
"matches": ["<all_urls>"],
"js": ["content.js"]
}
],
"browser_action": {
"default_title": "Practice",
"default_popup": "popup.html"
},
"permissions": [
"<all_urls>",
"tabs",
"storage",
"activeTab"
],
"background": {
"scripts": ["background.js"]
}
}
....
popup.html
<html>
<head>
....
<script src="popup.js"></script>
</head>
<body>
<input id="status" type="chckbox">
</body>
</html>
popup.js
$(document).ready(function(){
$on = $("#status");
//sends the settings to background to save it
$on.on("click",function(){
$obj = {"on":$on.prop("checked")}
browser.runtime.sendMessage($obj);
console.log("sending....");
})
})
What im trying to do is simply send a message to background script if the check box in popup.html is checked.
The problem is I cannot access the browser namespace in popup.js because its not content script or background script. And i cannot access the check box from the content scrip as it not linked to popup.html (if its linked i get reference error browser is not defined. I've tried countless google searches and spent hours reading web extension docs still cannot find an answer how to go around it any help appreciated.
I have good news for you - you can access the browser namespace in your browser action poupus, otherwise they would be pretty useless :)
Which means that something else is broken.
First, if you didn't do it yet, open 'browser toolbox' with Ctrl+Shift+Alt+I to see that you probably have a bit different kind of error there.
Then include this in your background.js :
function handleMessage(request, sender, sendResponse) {
console.log("Message from somewhere: ", request);
}
browser.runtime.onMessage.addListener(handleMessage);
To actually read the message.
See:
https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/browserAction
JavaScript running in the popup gets access to all the same WebExtension APIs as your background scripts, but its global context is the popup, not the current page displayed in the browser. To affect web pages you need to communicate with them via messages.
Edit, unrelated:
$on = $("#status");
You do realize that by doing so you refer to/create a global variable '$on', right? Did you mean:
var $on = $("#status");
?
I'm trying to write a Chrome extension that highlights certain words that were entered in extension's textfield
For example: I enter "web" in extension's area, press the button. On active tab all "web" words are should be highlighted.
I've found a nice web-pagethat has all the functions I need.
In my code, when I try to use them in my Extension, nothing works.
manifest file
{
"manifest_version": 2,
"name": "Word search & highlight",
"version": "1.0",
"icons": {
"16": "16x16.png",
"32": "32x32.png",
"48": "48x48.png",
"128": "128x128.png"
},
"content_scripts": [
{
"matches": [ "*://*/*" ],
"js": [ "popup.js"],
"run_at": "document_end"
}
],
"permissions": [
"tabs", "activeTab"
],
"browser_action": {
"default_title": "Start searching",
"default_icon": "48x48.png",
"default_popup": "popup.html"
}
}
popup.html
<!DOCTYPE html>
<html>
<head>
<script src="popup.js"></script>
<title></title>
</head>
<body>
<input type="text" id="searchtextfield"><br>
<input id="btn_save" value="Save" type="button">
<input id="btn_search" value="Search" type="button"><br>
</body>
</html>
And here's popup.js file: it's too long, so I made a pastebin document:
http://pastebin.com/g5ZenE48
I can't get innerHTML of webpage from these functions and I don't really understand how to make this all work.
sean-adams is correct, your browser action (popup.html) cannot communicate directly with your content script (popup.js). You can think of a content script as being an addition to whatever page the user is visiting, whereas the browser action is directly integrated as part of your chrome extension.
So, you will indeed need to use message passing to communicate. It's simple though. First, I recommend renaming your browser action popup to something like browser_popup.html. I'll use a stripped down example for brevity:
//browser_popup.html
<input type="button" id="my_button" value="Click Me">
<script src='browser_popup.js'></script>
You'll also want another file browser_popup.js for handling events.
//browser_popup.js
var button = document.querySelector('#my_button');
button.addEventListener('click', function() {
// Send message to active tab
chrome.tabs.query({active: true, currentWindow: true}, function(tabs) {
chrome.tabs.sendMessage(tabs[0].id, 'button_clicked');
});
});
In your content script (let's call it content.js) you need to listen for the message:
//content.js
chrome.runtime.onMessage.addListener(function(message) {
if (message == 'button_clicked') {
// code to modify page...
}
});
i am making a very simple exstension, when you click it, it is supposed to open a new tab, and send the user away to www.simplewebstats.com like this:
http://simplewebstats.com/process.php?domain="Domain the user is browsing"
So if he is browsing google.com, he is supposed to get sendt as
http://simplewebstats.com/process.php?domain=google.com
Here is what i have
Manifest.json
{
"background_page": "background.html",
"browser_action": {
"default_icon": "icon.png"
},
"description": "A free SEO tool for webmasters to track and display web data from most websites. ",
"name": "SimpleWebStats Site Report",
"permissions": [ "tabs", "http://www.simplewebstats.com/" ],
"version": "1.2",
"manifest_version": 2
}
background.html
<script src="js.js"></script>
js.js
chrome.browserAction.onClicked.addListener(function(tab){
chrome.tabs.getSelected(null,function(tab){
chrome.tabs.create({url:"http://www.simplewebstats.com/process.php?ref=plugins&processType=add&domain="+tab.url.match(/:\/\/(.[^/]+)/)[1]});
});
});
Your define the background.html page in an older version of manifest.json (lower then 1)
The newer version is:
"background": {
"page": "background.html"
},
Then again - you can only define a background script (no need for the html):
"background": {
"scripts": ["background.js"]
},
What am I doing wrong? I want to run a function when clicking "Show me some foo".
manifest.json browser_action
"browser_action": {
"default_icon": "img/icon.png",
"default_popup": "popup.html"
},
popup.html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<script type="text/javascript" src="js/popup.js"></script>
</head>
<body>
<div class="changes">
<span class="reset">Show me some foo
</span>
</div>
</body>
</html>
popup.js
chrome.browserAction.onClicked.addListener(function(tab) {
chrome.tabs.executeScript(null,
{file:"reset.js"});
});
reset.js
var el = document.getElementById('foo');
el.onclick = showFoo;
function showFoo() {
alert('I am foo!');
return false;
}
Full manifest.json file
{
"name": "App name",
"version": "1.0.2",
"manifest_version": 2,
"description": "Desc.",
"permissions": [
"tabs"
],
"browser_action": {
"default_icon": "img/icon.png"
},
"background": {
"page": "background.html"
},
"browser_action": {
"default_icon": "img/icon.png",
"default_popup": "popup.html"
},
"content_scripts": [
{
"matches": [
"http://*/*",
"https://*/*"
],
"js": ["js/myscript.js"],
"exclude_matches":[
"http://site.com/*"
]
}
],
"web_accessible_resources": [
"chrome_ex_oauth.html"
]
}
I'm not sure what you are trying to do, but I'll explain your code to you:
user clicks a browserAction
popup window is crated and scripts from popup.html are loaded
popup.js loads and registers a listener chrome.browserAction.onClicked.addListener
user closes a popup window (by clicking anywhere outside it or on the browserAction again)
pupup.html page is unloaded
chrome.browserAction.onClicked.addListener listener is unregistered
As you can see reset.js is never loaded as it's never injected. What's more, you can't have a popup.html and chrome.browserAction.onClicked.addListener in the same extension ("This event will not fire if the browser action has a popup." source).
You probably want to put chrome.browserAction.onClicked.addListener into the background page so that reset.js is injected to current page whenever browserAction is clicked. And, as I mentioned above, for chrome.browserAction.onClicked.addListener to fire, you need to get rid of "default_popup": "popup.html" from manifest.
If you wanted to inject a script to popup.html - it doesn't make much sense. You have full control over popup.html and you can simply put reset.js in the <head>.