How find to whether my Chrome extension was called by shortcut? - google-chrome-extension

I have a Chrome extension with a popup that can also be opened by a shortcut. When the popup gets opened, can I find out whether the user has used the shortcut or whether they have clicked on the extension icon?
The reason is that I'd like to hint users to use the shortcut, but I don't want to show that hint to users who already know and use the shortcut.
Popup and shortcut are defined like this in manifest.json:
"browser_action": {
"default_icon": "images/icon48.png",
"default_popup": "popup.html",
"default_title": "__MSG_tooltip__"
},
"commands": {
"_execute_browser_action": {
"suggested_key": {
"default": "Ctrl+Shift+Space"
}
}
},

chrome.browserAction.onClicked.addListener
Not available, because:
Fired when a browser action icon is clicked. This event will not fire
if the browser action has a popup.
We has popup.
chrome.commands.onCommand.addListener
Not available, because:
The '_execute_browser_action' and '_execute_page_action' commands are
reserved for the action of opening your extension's popups. They won't
normally generate events that you can handle.
May try inject press listener to some page and track pressed of keys (on each page).
var isPressed;
document.body.addEventListener("keydown", function (e) {
if (!(e.keyCode != 17) || !(e.keyCode != 16) || !(e.keyCode != 32)) return;
isPressed = true;
});
From popup in moment expand send message to content_scripts:
chrome.tabs.query({active: true, currentWindow: true}, function (tabs) {
chrome.tabs.sendMessage(tabs[0].id, {action: "isPressed"}, function (responce) {
if (responce) {
}
});
});
After message receiving, listener in content scripts send variable isPressed as response:
chrome.runtime.onMessage.addListener(function (message, sender, response) {
if (message.action == "isPressed") {
response(isPressed);
}
});
If variable is true, means called via keystrokes, else on click on icon.

can I find out whether the user has used the shortcut or whether they
have clicked on the extension icon?
There seems to be no clean direct way of detecting that.
Since I put some effort into trying to find a workaround, I would like to share what I have considered/tried and reasons why it doesn't work:
Attach the keyboard shortcut to some custom command, modify popup page and then open it programmatically.
Doesn't work because there is no way to open the popup programmatically, at least not in current stable version of Chrome (v50).
Create a custom command with the same shortcut as "_execute_browser_action" and use it to send a message to the popup.
Doesn't work because two commands cannot share the same shortcut.
Try to capture keyup in the popup page immediately after loading.
I tested this and it seemed to work at first, but it is definitely not reliable. If the user only presses the keyboard shortcut very briefly, the keyup event is fired before the popup page gets a chance to register a listener for it.
Capture keydown on pages using a content script and then send a message to the popup page to let it know that the keyboard shortcut was pressed (as suggested by UserName above).
This should work on most pages, but the content script won't be able to capture the keypress in address bar and on certain pages (chrome://, chrome-extension://).
Difficult to implement because you need to take into account the fact that users can customize the shortcut on chrome://extensions page. Finding the currently assigned shortcut programmatically to test against it in the content script is surprisingly difficult, because chrome.commands.getAll() provides localized key names (eg. "Ctrl+Shift+Space" in English, but "Ctrl+Shift+Mezera" in Czech) There are languages where even Ctrl and Shift don't stay in English.

Related

How to cause a chrome extension to close only by clicking on the icon or a button

I am developing a chrome extension, in which I have used iframe, which I want to keep open even if we do some activity on the active web page itself or open a new tab or a new window. The extension should get closed only on clicking on the extension icon again or by clicking a close button, present on the extension itself. I am hinting on something like join pouch extension.
Other questions pertaining to this topic only caters to opening a window through extension which remains open or keeping the extension popup open just for debugging purposes, by inspecting the popup.
I know there is a way to do this, since I have seen some extensions as such, but am unable to find.
You can embed that iframe into the DOM structure of every single page you open. Unfortunately, Google doesn't provide any solution besides a default popup that disappears when the first click outside of it happens. The flipside is, you'll need to run one instance of your content script per page, which might mean there will be hundreds of them running (at least for me as I'm a compulsive new-tab-opener).
This is one of the ways, how you can approach this.
Step 1. As I've already said, the default action on icon click is opening a popup. You can disable that behaviour by including the following entry in your manifest.json:
"browser_action": {},
Step 2. The next thing would be creating a content script that runs on every page. In your manifest, it would look like this:
"content_scripts": [
{
"run_at": "document_end",
"matches": ["*://*/*"],
"js": ["path/to/your/content/script.js"]
}
],
Step 3.
Your content script should embed that iframe you mentioned into the currently open page (when the DOM fully loaded).
window.addEventListener('load', function load(event) {
var iframe = document.createElement('iframe');
/* some settings, these are mine */
iframe.style.width = "250px";
iframe.style.background = "#eee";
iframe.style.height = "100%";
iframe.style.position = "fixed";
iframe.style.top = "0px";
iframe.style.right = "0px";
iframe.style.zIndex = "1000000000000000";
iframe.frameBorder = "none";
/* end of settings */
iframe.src =
chrome.runtime.getURL("path/to/contents/of/your/iframe.html");
document.body.appendChild(iframe);
});
Step 4.
You must make sure, people can access iframe.html. Add this line to your manifest file:
"web_accessible_resources": ["path/to/contents/of/your/iframe.html"],
(or just add that file to the list if it was already there.
Step 5.
Create a function in your content script that knows how to hide your iframe. Something like that:
function toggle_iframe() {
if (iframe.style.width == "0px"){
iframe.style.width="250px";
} else {
iframe.style.width="0px";
}
}
Now, the only thing left is to know when to call it.
Step 6.
Unfortunately, background script is the only place that can get information about extension icon being clicked. Add this snippet to your background script:
chrome.browserAction.onClicked.addListener(function(){
chrome.tabs.query({active: true, currentWindow: true}, function(tabs){
chrome.tabs.sendMessage(tabs[0].id, { action: "must_toggle_iframe" });
})
});
It sends a message, when the icon has been clicked.
Step 7.
The last part is to allow your content script to receive that message. Your content script needs a listener.
chrome.runtime.onMessage.addListener(function(msg, sender) {
if (msg.action == "must_toggle_iframe"){
toggle_iframe();
}
}
Of course, the solution is not ideal, but you could refine it. For example by remembering in the chrome.storage.local/chrome.storage.sync whether the iframe has been hidden.

what is the use of window.open('','_self').close(); in chrome extension

When I click the extension icon, a popup is shown.
After that, when I try to click "URL restrictions", it will open a window, after that when I click the popup again, the popup is overlapping that url restriction window.
The above issue happens on Windows only, not on Linux.
So I have added window.open('','_self').close(); which apparently fixed the issue. But not exactly. Is it correct? I have referred this Link and Link2 but can not understand the meaning.
What is the purpose of window.open('','_self').close();?
EDIT: this is my popup.js
function click(e) {
var windowObj = window.open(site_exception_url, 'url_window', params);
windowObj.focus();
window.close();
window.open('','_self').close();
return false;
}
On Windows the popup isn't closed automatically after a new window is opened from a link within the popup.
Close it in the click handler manually, this won't hurt Linux but will help on Windows:
document.addEventListener("click", function(event) {
if (event.target.localName == "a") {
close();
}
});
The related questions linked in your question don't apply here as the first is for userscripts, not extensions, and the second isn't for popups shown by the browser when you click the toolbar button.

Cool way to reset the browser action badge?

I have an extension that implements a browser action.
Of course, the browser action is allways visible, but it has a special significance in certain urls. So, I use filtered events to listen to those urls and set the proper badge
chrome.webNavigation.onDOMContentLoaded.addListener(
function(tab){
chrome.browserAction.setBadgeText({
text:'bdge',
tabId: tab
});
},
{'url':[{hostSuffix: 'somedomain.com', pathPrefix: 'somePath/'}]}
);
Is there some "elegant" way to reset the badge when the user navigates out from that page, without listening every single tab navigation?
Should I execute a content script to hang on some exiting event and send a message?
Thank you very much,
It seems to me that a good solution would be to use chrome.tabs.onUpdated.
In your background page, you would have something like that:
chrome.tabs.onUpdated.addListener(function(tabId, changeInfo, tab) {
// using a regex or however else you want to test the URL
if (/somedomain\.com\/somePath\//.test(changeInfo.url)) {
chrome.browserAction.setBadgeText({
text: 'bdge',
tabId: tabId
});
} else {
chrome.browserAction.setBadgeText({
text: '',
tabId: tabId
});
}
});
I know you wrote "without listening every single tab navigation" but I'm not sure why you want to avoid this.
This is what documentation doesn't tell you: Chrome actually resets badge automatically when user navigates away.
When you set a browser action's badge only to a specific tab, like
chrome.browserAction.setBadgeText({
text: 'ABCD', // My badge's text should be only 4 characters long
tabId: 1234 // Any tab, ussually a var here, not a constant
});
Chrome shows the badge on the browser action button only when that tab is the active tab in the window. Its text resets to '' when the user navigates away in that tab. No need for special action to reset it.

Communicating with a content script on active tab from a Chrome extension's page action popup

I'm not getting how to pass data between content script and page action popup.
I've started with the following simple skeleton, that shows an page action for any page having a minus-dash in title:
Extension manifest (manifest.json):
{
…
"permissions": ["http://example.org/*"],
"background": {"scripts": ["background.js"]},
"page_action": {"default_popup": "popup.html", …},
"content_scripts": {
"matches": ["http://example.org/*"],
"js": ["content.js"]
}
}
Background script (background.js):
chrome.extension.onRequest.addListener(function (msg, sender, respond) {
if (msg && msg.what === "match") {
console.log("Match:", msg.title);
chrome.pageAction.show(sender.tab.id);
}
}
Content script (content.js), checking document titles:
var title = document.title;
if (title.indexOf("-") >= 0) {
chrome.extension.sendRequest({"what": "match", "title": title});
}
Now, in a page action's popup, I want to show matched page's title. Not the last loaded page's title (as would be done by using this answer), but the title of the active tab.
My first though was to send a query to the content script, but according to documentation chrome.extension.sendMessage will send it to all listeners (i.e. all my content scripts on all tabs), without any clear definition on whose response I'll receive back. Also, I can't use chrome.tabs.sendMessage as it requires tabId. Trying to find the current tab using chrome.tabs.getCurrent will return null, as the query comes from non-tab context (from a popup).
I guess I could probably use chrome.tabs.executeScript to communicate, but this just feels dirty.
Still, I believe, this is a basic thing that should be very simple to do and I'm just missing something. Could someone, please, help me, preferably, with an example code?
Update: I've found Mappy example extension and it uses chrome.tabs.onUpdated to keep track of the active tab. This, unfortunately, requires tabs permission. Personally, I'd like to use least privileges possible.
So, is it just unfortunately bad permission system design and I have no choice but to do it this way, or there's any workaround? I'd be happy if chrome.pageAction.onClicked event handler (which provides Tab object that I need) would allow me to show a popup...
I think you need to add the onClick event listener in your popup:
chrome.pageAction.onClicked.addListener(function(tabs.Tab tab) {...});
See documentation here.
Callback of the event listener would provide you the tabId which would surely be the active tab.
There are multiple Problems in your code
chrome.extension.sendRequest in chrome.extension.sendRequest({"what": "match", "title": title}); is deprecated
chrome.pageAction.onClicked will not fire when you have "page_action": {"default_popup": "popup.html", …}, in your manifest.
chrome.extension.sendMessage will send it to all listeners (i.e. all my content scripts on all tabs), is an invalid assumption, it will send to Extension Pages.
I tried to read your question multiple times but couldn't understand what is you want to achieve, could you explain it?

How to write an extension to close tabs on "back" attempt when there's no previous page?

I find myself more and more using the touchpad gesture of 3 fingers to the left or right in order to perform a "back" or "forward" in Google Chrome (on my Asus Zenbook, but I believe there's a similar gesture on Macs)
I found that when browsing, I open a tab to read something (Like a like from Twitter or Facebook) and when I'm done my instinct is to go "back" to get back to the previous tab I was browsing on. (I think I got that instinct from using Android a lot).
I figured that I need a Chrome extension that would close my current tab if I'm attempting to go "back" in a tab that doesn't have a previous page in its history.
I went over the Chrome events and various methods I can invoke and while there's a "forward_back" transition qualifier in the WebNavigation api, the onCommitted event doesn't fire when attempting to go "back" using the touchpad gesture or Alt+left keyboard shortcut.
Also, I couldn't find how I can access a current tab's history to see if the page I'm at doesn't have a previous one in the stack.
Ideas anyone?
function noHistory(tabId) {
// TODO
}
function getCurrentTabId() {
// TODO
}
function userHitBack() {
tabId = getCurrentTabId();
if (noHistory(tabId)) {
chrome.tabs.remove(tabId)
}
}
function attachEvent() {
// TODO attach userHitBack
}
attachEvent();
To catch the "back" event, you need to handle specific key pressed to call your "userHitBack" function. Something like this:
document.onkeydown = function() {
if (keyId == ...)
userHitBack()
}
You can use this to your advantage as you can bind any key to trigger the close of the tab.
To check the tab history length use this:
window.history.length
It is html5 historyAPI

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