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How to (sort of) add code to fullcalendar's renderEvents handler?

I'm using fullcalendar 1.6.3 along with Drupal 7 (thus the need, for now, to be back on 1.6.3). I have some code that I'd like to run every time the view of my calendar changes (via ajax requests) -- forward or backward in time, or between month/week/day view.
Based on some tests, I could do this by hacking the source for renderEvents:
function renderEvents(modifiedEventID) { // TODO: remove modifiedEventID hack
if (elementVisible()) {
currentView.setEventData(events); // for View.js, TODO: unify with renderEvents
currentView.renderEvents(events, modifiedEventID); // actually render the DOM elements
currentView.trigger('eventAfterAllRender');
// my_code_here();
}
}
but that would of course be Wrong. Unfortunately, I can't figure out any other way to do it, probably because of some obvious gap in my Javascript knowledge. I tried setting up an event handler on eventAfterAllRender:
var eventAfterAllRenderEvent = new Event('eventAfterAllRender');
document.addEventListener('eventAfterAllRender', function (e) {my_code_here() }, false);
document.dispatchEvent(eventAfterAllRenderEvent);
but that (for me) only runs on page load, not after the ajax events.
This is probably more of a Javascript question than a fullcalendar question, but is there any advice out there? I'm really trying to not hack core; thanks!

According to the documentation eventAfterAllRender is a callback, so you can do this:
$('#your-calendar-element').fullCalendar({
eventAfterAllRender: function (view) {
// add your code here
}
});

In a Firefox restartless add-on, how do I run code when a new window opens (listen for window open)?

I am starting to build a restartless Firefox add-on and I am having trouble setting up the bootstrap.js. Everyone seems to agree that the core of a bootstrap.js is pretty much boilerplate code, along these lines:
const Cc = Components.classes;
const Ci = Components.interfaces;
function startup() {
let wm = Cc["#mozilla.org/appshell/window-mediator;1"].getService(Ci.nsIWindowMediator);
let windows = wm.getEnumerator("navigator:browser");
while (windows.hasMoreElements()) {
let domWindow = windows.getNext().QueryInterface(Ci.nsIDOMWindow);
// then can control what happens with domWindow.document
}
}
function shutdown() {}
function install() {}
function uninstall() {}
This code works and I can control things in the existing windows. For example, domWindow.alert("text") successfully creates a standard alert saying "text" on every window that is currently open.
However, I can't find any code that will allow me to do things in new windows; i.e. those created after the script runs. What is the correct way to handle the creation of new windows and gain control over them, to the point where I could get another "text" alert from one when it is created?
Edit: Using the nsWindowMediator class and the code sample from MDN, I now have this:
var windowListener = {
onOpenWindow: function (aWindow) {
try {
let domWindow = aWindow.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindowInternal || Ci.nsIDOMWindow);
domWindow.addEventListener("load", function () {
domWindow.removeEventListener("load", arguments.callee, false);
//window has now loaded now do stuff to it
domWindow.alert("text");
}, false);
} catch (err) {
Services.prompt.alert(null, "Error", err);
}
},
onCloseWindow: function (aWindow) {},
onWindowTitleChange: function (aWindow, aTitle) {}
};
function startup(aData, aReason) {
// Load into any existing windows
try {
let wm = Cc["#mozilla.org/appshell/window-mediator;1"].getService(Ci.nsIWindowMediator);
let windows = wm.getEnumerator("navigator:browser");
while (windows.hasMoreElements()) {
let domWindow = windows.getNext().QueryInterface(Ci.nsIDOMWindow);
loadIntoWindow(domWindow);
}
} catch (err) {
Services.prompt.alert(null, "Error", err);
}
Services.wm.addListener(windowListener);
}
However, there is still no output from the onOpenWindow call - the "text" alert does not appear, nor does the error alert in the catch block. I can confirm that onOpenWindow is actually being entered; if I put a Services.prompt.alert() at the beginning of onOpenWindow, I get the alert when I create a new window. Unfortunately, I get an infinite loop of alerts and I have no idea why.

However, I can't find any code that will allow me to do things in new windows; i.e. those created after the script runs. What is the correct way to handle the creation of new windows and gain control over them, to the point where I could get another "text" alert from one when it is created?
The correct way to act on each window when it opens is to use addListener() from nsIWindowMediator. The example code below does this. The nsIWindowMediator is included in Services.jsm and is accessed through Services.wm.addListener(WindowListener). In order to use a window listener, you have to pass it an nsIWindowMediatorListener (ref2) object. An nsIWindowMediatorListener contains three keys: onOpenWindow, onCloseWindow, and onWindowTitleChange. Each should be defined as a function which will be called when the appropriate event occurs.
The MDN document How to convert an overlay extension to restartless in "Step 9: bootstrap.js" contains an example of a basic bootstrap.js which will run the code in the function loadIntoWindow(window) for each currently open browser window and any browser window which opens in the future. I have used code modified from this in a couple of different add-ons. The example is substantially similar to the code you are already using. The example is (slightly modified):
const Ci = Components.interfaces;
Components.utils.import("resource://gre/modules/Services.jsm");
function startup(data,reason) {
// Load this add-ons module(s):
Components.utils.import("chrome://myAddon/content/myModule.jsm");
// Do whatever initial startup stuff is needed for this add-on.
// Code is in module just loaded.
myModule.startup();
// Make changes to the Firefox UI to hook in this add-on
forEachOpenWindow(loadIntoWindow);
// Listen for any windows that open in the future
Services.wm.addListener(WindowListener);
}
function shutdown(data,reason) {
if (reason == APP_SHUTDOWN)
return;
// Unload the UI from each window
forEachOpenWindow(unloadFromWindow);
// Stop listening for new windows to open.
Services.wm.removeListener(WindowListener);
// Do whatever shutdown stuff you need to do on add-on disable
myModule.shutdown();
// Unload the module(s) loaded specific to this extension.
// Use the same URL for your module(s) as when loaded:
Components.utils.unload("chrome://myAddon/content/myModule.jsm");
// HACK WARNING: The Addon Manager does not properly clear all add-on related caches
// on update. In order to fully update images and locales, their
// caches need clearing here.
Services.obs.notifyObservers(null, "chrome-flush-caches", null);
}
function install(data,reason) { }
function uninstall(data,reason) { }
function loadIntoWindow(window) {
/* call/move your UI construction function here */
}
function unloadFromWindow(window) {
/* call/move your UI tear down function here */
}
function forEachOpenWindow(todo) {
// Apply a function to all open browser windows
var windows = Services.wm.getEnumerator("navigator:browser");
while (windows.hasMoreElements())
todo(windows.getNext().QueryInterface(Ci.nsIDOMWindow));
}
var WindowListener = {
onOpenWindow: function(xulWindow) {
var window = xulWindow.QueryInterface(Ci.nsIInterfaceRequestor)
.getInterface(Ci.nsIDOMWindow);
function onWindowLoad() {
window.removeEventListener("load",onWindowLoad);
// Only add UI changes if this is a browser window
if (window.document.documentElement.getAttribute("windowtype")
== "navigator:browser")
loadIntoWindow(window);
}
window.addEventListener("load",onWindowLoad);
},
onCloseWindow: function(xulWindow) { },
onWindowTitleChange: function(xulWindow, newTitle) { }
};
While there is quite a bit more that your might want to do in your bootstrap.js code, the above is organized reasonably well and keeps all of the code to load into the Firefox UI within loadIntoWindow(window) and unloading the UI within unloadFromWindow(window). However, it should be noted that some UI elements you should only be adding/removing once (e.g. australis widgets, like buttons) and other elements (e.g. direct changes to the Firefox DOM) have to be added once in each window.
Unfortunately, I get an infinite loop of alerts and I have no idea why.
One of the significant differences between this example and what you are currently using is the test for the type of window that has opened. This is done so that we are only acting on newly opened windows which are browser windows instead of all newly opened windows:
if (window.document.documentElement.getAttribute("windowtype") == "navigator:browser")
loadIntoWindow(window);
The problem you describe of getting an infinite loop of alert() popups is caused by not checking to make sure that you are only acting on browser windows. The alert() popup is a window. Thus, you are calling alert() for every alert() window you open which, of course, just opens another alert() window on which you call alert(). This is your infinite loop.
Additional references:
1. Working with windows in chrome code

However, I can't find any code that will allow me to do things in new windows
When working with XPCOM objects you generally want to study their interfaces, which are often found on MDN. In this case your starting point would be nsIWindowMediator, since that's the service you're using in line 5.
As you can see it has an addListener function, which takes a parameter implementing nsIWindowMediatorListener. There's a code-example right there on the page.
But let's assume for the moment there isn't a code example. You could search for the interface on MDN, but it isn't listed. The next step would be searching MXR for the .idl. idl = interface description language
Once you got the interface contract you can more or less just implement it in javascript, at least for listeners. Implementing your own xpcom services would be a little more complicated.
Searching the addon sdk can often provide some hints too. In this case they don't seem to be using .addListener, but the file hints at another interesting service, which in turn you can find on MDN: nsIWindowWatcher.
Basically, if you're writing restartless addons you're rummaging through the entrails of firefox and will have to do some detective work to find the exact components you need. If you want something more convenient I would recommend the addon sdk, which provides a more organized but also more restricted set of commonly used APIs

chrome.notifications.update() or create()

I want my chrome extension to take a notification.id, and:
Update an existing notification if it does exist.
OR
Create a new notification if it doesn't exist.
Calling clear() then create() is not ideal, since the animation is visually jarring for both remove() and create() methods, where I want to update without animations. Plus, obviously, calling update() on a disappeared notification doesn't do anything.
Is there an easy way to implement this?

Edit: This approach no longer works on any platform except ChromeOS due to the removal of Chrome's Notification Center.
Possible ideas to work around it include using requireInteraction: true flag on notifications to fully control notification lifetime.
There is a dirty trick for re-showing a notification. If you change a notification's priority to a higher value, it will be re-shown if it exists.
function createOrUpdate(id, options, callback) {
// Try to lower priority to minimal "shown" priority
chrome.notifications.update(id, {priority: 0}, function(existed) {
if(existed) {
var targetPriority = options.priority || 0;
options.priority = 1;
// Update with higher priority
chrome.notifications.update(id, options, function() {
chrome.notifications.update(id, {priority: targetPriority}, function() {
callback(true); // Updated
});
});
} else {
chrome.notifications.create(id, options, function() {
callback(false); // Created
});
}
});
}

Xan's answer no longer works on Windows, MacOS, or Linux. At this point the only way to make sure your notification displays, no matter what, is to create a new notification.
If you want to prevent multiple notifications from being on screen, you'll have to clear the old notification and replace it with a new one. This is demonstrated below.
NOTIFICATION_ID = "some_random_string";
function showNotification ( ... , callback) {
chrome.notifications.clear(NOTIFICATION_ID, function(cleared) {
var options = {
// whatever
};
chrome.notifications.create(NOTIFICATION_ID, options, callback);
});
}
Of course, this results in an animation of existing notification getting dismissed and a new notification immediately taking its place, but unfortunately this is unavoidable.

Google Chrome editing Javascript on the fly

I've tried to ease my life by using Google Chrome's devtools and as I've tried to modify javascript of page on fly but it seems to behave unexpectedly
I have this function that is called every frame of the game
View.prototype.onHit = function() {
for(var i = 0; i < this.obstacles.length; i++) {
if(this.obstacles[i].dealsDamage) {
//deal damage
} else {
//do something else
}
}
}
and when I open it on chromes "Sources tab" and pause execution and add something simple such as
console.log("hey");
it starts printing text "hey" on console as expected but the moment i modify some code such as the if check to
if(!this.obstacles[i].dealsDamage) {
//do something else
} else {
//deal damage
}
inverting the behaviour and save the document, the code doesnt take effect and the logging source changes to View.js (old)
and anything I change after that doesn't affect the running javascript

The "(old)" script normally should only appear if the more complex changes are applied. Namely, if you change a function parameter number or start (and lamently stop) using a variable from outer scope.
If live edit fails to work in such simple use-case as you describe, it could be a good thing to file to http://crbug.com

How can I detect with JavaScript/jQuery if the user is currently active on the page?

I am needing to detect when a user is inactive (not clicking or typing) on the current page for more than 30 minutes.
I thinking it might be best to use event blubbling attached to the body tag and then just keep resetting a timer for 30 minutes, but I'm not exactly sure how to create this.
I have jQuery available, although I'm not sure how much of this will actually use jQuery.
Edit: I'm more needing to know if they are actively using the site, therefore clicking (changing fields or position within a field or selecting checkboxes/radios) or typing (in an input, textarea, etc). If they are in another tab or using another program, then my assumption is they are not using the site and therefore should be logged out (for security reasons).
Edit #2: So everyone is clear, this is not at all for determining if the user is logged in, authenticated or anything. Right now the server will log the user out if they don't make a page request within 30 minutes. This functionality to prevent the times when someone spends >30 minutes filling in a form and then submitting the form only to find out that they haven't been logged out. Therefore, this will be used in combination with the server site to determine if the user is inactive (not clicking or typing). Basically, the deal is that after 25 minutes of idle, they will be presented with a dialog to enter their password. If they don't within 5 minutes, the system automatically logs them out as well as the server's session is logged out (next time a page is accessed, as with most sites).
The Javascript is only used as a warning to user. If JavaScript is disabled, then they won't get the warning and (along with most of the site not working) they will be logged out next time they request a new page.

This is what I've come up with. It seems to work in most browsers, but I want to be sure it will work everywhere, all the time:
var timeoutTime = 1800000;
var timeoutTimer = setTimeout(ShowTimeOutWarning, timeoutTime);
$(document).ready(function() {
$('body').bind('mousedown keydown', function(event) {
clearTimeout(timeoutTimer);
timeoutTimer = setTimeout(ShowTimeOutWarning, timeoutTime);
});
});
Anyone see any problems?

Ifvisible.js is a crossbrowser lightweight solution that does just that. It can detect when the user switches to another tab and back to the current tab. It can also detect when the user goes idle and becomes active again. It's pretty flexible.

You can watch mouse movement, but that's about the best you're going to get for indication of a user still being there without listening to the click event. But there is no way for javascript to tell if it is the active tab or if the browser is even open. (well, you could get the width and height of the browser and that'd tell you if it was minimized)

I just recently did something like this, albeit using Prototype instead of JQuery, but I imagine the implementation would be roughly the same as long as JQuery supports custom events.
In a nutshell, IdleMonitor is a class that observes mouse and keyboard events (adjust accordingly for your needs). Every 30 seconds it resets the timer and broadcasts an state:idle event, unless it gets a mouse/key event, in which case it broadcasts a state:active event.
var IdleMonitor = Class.create({
debug: false,
idleInterval: 30000, // idle interval, in milliseconds
active: null,
initialize: function() {
document.observe("mousemove", this.sendActiveSignal.bind(this));
document.observe("keypress", this.sendActiveSignal.bind(this));
this.timer = setTimeout(this.sendIdleSignal.bind(this), this.idleInterval);
},
// use this to override the default idleInterval
useInterval: function(ii) {
this.idleInterval = ii;
clearTimeout(this.timer);
this.timer = setTimeout(this.sendIdleSignal.bind(this), ii);
},
sendIdleSignal: function(args) {
// console.log("state:idle");
document.fire('state:idle');
this.active = false;
clearTimeout(this.timer);
},
sendActiveSignal: function() {
if(!this.active){
// console.log("state:active");
document.fire('state:active');
this.active = true;
this.timer = setTimeout(this.sendIdleSignal.bind(this), this.idleInterval);
}
}
});
Then I just created another class that has the following somewhere in it:
Event.observe(document, 'state:idle', your-on-idle-functionality);
Event.observe(document, 'state:active', your-on-active-functionality)

Ifvisible is a nice JS lib to check user inactivity.
ifvisible.setIdleDuration(120); // Page will become idle after 120 seconds
ifvisible.on("idle", function(){
// do something
});

Using jQuery, you can easily watch mouse movement, and use it to set a variable indicating activity to true, then using vanilla javascript, you can check this variable every 30 minutes (or any other interval) to see if its true. If it's false, run your function or whatever.
Look up setTimeout and setInterval for doing the timing. You'll also probably have to run a function every minute or so to reset the variable to false.

Here my shot:
var lastActivityDateTime = null;
function checkActivity( )
{
var currentTime = new Date();
var diff = (lastActivityDateTime.getTime( ) - currentTime.getTime( ));
if ( diff >= 30*60*1000)
{
//user wasn't active;
...
}
setTimeout( 30*60*1000-diff, checkActivity);
}
setTimeout( 30*60*1000, checkActivity); // for first time we setup for 30 min.
// for each event define handler and inside update global timer
$( "body").live( "event_you_want_to_track", handler);
function handler()
{
lastActivityDateTime = new Date();
// rest of your code if needed.
}

If it's a security issue, doing this clientside with javascript is absolutely the wrong end of the pipe to be performing this check. The user could easily have javascript disabled: what does your application do then? What if the user closes their browser before the timeout. do they ever get logged out?
Most serverside frameworks have some kind of session timeout setting for logins. Just use that and save yourself the engineering work.
You can't rely on the assumption that people cannot log in without javascript, therefore the user has javascript. Such an assumption is no deterrent to any determined, or even modestly educated attacker.
Using javascript for this is like a security guard handing customers the key to the bank vault. The only way it works is on faith.
Please believe me when I say that using javascript in this way (and requiring javascript for logins!!) is an incredibly thick skulled way to engineer any kind of web app.

Without using JS, a simpler (and safer) way would simply be to have a lastActivity timestamp stored with the user's session and checking it on page load. Assuming you are using PHP (you can easily redo this code for another platform):
if(($_SESSION['lastAct'] + 1800) < time()) {
unset($_SESSION);
session_destroy();
header('Location: session_timeout_message.php');
exit;
}
$_SESSION['lastAct'] = time();
and add this in your page (optional, the user will be logged out regardless of if the page is refreshed or not (as he logs out on next page log)).
<meta http-equiv="refresh" content="1801;" />

You can add and remove classes to the document depending on the user active status.
// If the window is focused, a mouse wheel or touchmove event is detected
$(window).on('focus wheel touchmove', function() {
$( 'html' ).addClass('active').removeClass('inactive');
});
// If the window losses focus
$(window).on('blur', function() {
$( 'html' ).addClass('inactive').removeClass('active');
});
After that, you can check every while if the html has the "active" class and send an AJAX request to check the session status and perform the action you need:
setInterval( function() {
if ( $( 'html' ).hasClass('active') ) {
//Send ajax request to check the session
$.ajax({
//your parameters here
});
}
}, 60000 ); /* loops every minute */

If your concern is the lost of information for the user after a login timeout; another option would be to simply store all the posted information upon the opening of a new session (a new session will always be started when the older session has been closed/scrapped by the server) when the request to a page is made before re-routing to the logging page. If the user successfully login, then you can use this saved information to return the user back to where he was. This way, even if the user walk away a few hours, he can always return back to where he was after a successful login; without losing any information.
This require more work by the programmer but it's a great feature totally appreciated by the users. They especially appreciate the fact that they can fully concentrate about what they have to do without stressing out about potentially losing their information every 30 minutes or so.