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Javascript events in Chrome and Firefox

I noticed that these function doesn't work good in Firefox, but does in Chrome.
I use these function in a game in Js to shoot bullet (left mouse click) and to create a fireball all around the player with the right click that burns everyone in a small radius.
document.onclick = function(event) {
if(!player){ //to avoid onclick to be used before calling Player();
return;
}
if(player.canAttack && player.distance >= 80) { //not for sword attack
performAttack(player);
player.canAttack = false;
}
if(player.distance < 80)
performAttack(player);
//event.preventDefault();
}
document.oncontextmenu = function(event) {
//hide default behaviour of right click -> no context menu popup
event.preventDefault();
if(player.obtainedGadjet > 0) {
player.pressingMouseRight = true;
performSpecialAttack(player);
}
}
In the performAttack function I set player.isStopped = true, so my updatePlayer() doesn't change player.x and player.y while he's attacking. The same for the fireball attack. I want my player stays there.
It works in chrome, my player stops, attacks,and then can moves again, but in Firefox if I right click it somethimes acts instead as I have left clicked, so shoot the magic ball, and maybe then the fireball too. Furthermore, my player ignore isStopped = true, it seems like in Firefox oncontextmenu has "lower priority" than other events.
Any idea?
Thanks

Please note that a click event contains information about which button was pressed. You can try yourself with something like:
document.addEventListener('click', function(ev){
console.log(ev.button);
});
And, yes, click events are fired when you right-click, even if you're doing something on related contextmenu events.
So your code should look a bit more like
document.addEventListener('click', function(ev){
if (ev.button === 0) {
// Perform primary action
} else if (ev.button === 2) {
// Perform secondary action
}
});
document.addEventListener('contextmenu', function(ev){
ev.preventDefault();
});

Using the same click event is advisable as said by Ivan. You may also want to read this other discussion here on SO about best practices and why it's not always good to disable default right click behaviour (i.e.: it's not always guaranteed to work).

Switch to touch events with SnapSvg

I need to use touch events for touch screens, and mouseevents for regular Desktop for my website using Snap SVG.
I have mouse events like :
_Button.mousedown(function(){
// Do Stuff
});
How can I easily switch to touch events such as 'touchstart' when my user comes from a tablet ?
I don't want to duplicate code, and checks if its a touchscreen, like having 20* times this kind of code :
_Button.mousedown(function(){
// Do Stuff
});
if ( touchSreenFlag === true) {
_Button.mousedown(function(){
// Do Stuff
});
}
Thx

Here we go :
SVGTHING.mouseup(function(e){
if (e.type === 'touchend') {
// Stop propagation : on touch devices the first click will be used and not the second.
e.stopPropagation();
e.preventDefault();
}
do_stuff();
});

Prevent page scroll on drag in IOS and Android

I'm working on a html5 canvas game, but I don't know how to handle touch events. When a user touch the screen, and drag, then the browser will scroll the page. I would like to prevent it, and get the touch start, and touch end position. Is it possible?
Thanks in advance

You need to override the default touch behaviour to stop touchevents dragging the page. Clearly, you'll need to handle them again if your page becomes larger than the available area, but as you're making a game, going to assume you're doing 100%/100% layout.
function preventBehavior(e) {
e.preventDefault();
};
document.addEventListener("touchmove", preventBehavior, {passive: false});
Edit: here's the W3C recommendation talking about touch events, which might be handy for you.

Due to breaking changes made in recent versions of Chrome, the above answers are no longer correct. Attaching a touch event listener to the document or body elements will cause the event listener to be registered in "passive" mode, which causes calls to preventDefault to be ignored.
There are two solutions:
The preferred solution is to use the CSS style touch-action to specify that no scrolling should happen (e.g. with the value "none")
In cases where this is not appropriate (e.g. if the type of interaction should change dynamically in a way that cannot be determined before the gesture begins) then the event listener must be registered with the third parameter set to { passive: false } (you should perform browser detection to ensure that this style is supported first, though).

If you don't want to use jQuery mobile or any other library then you can try this.
var startX, startY, endX, endY;
document.addEventListener("touchstart", function(e){
startX = e.touches[0].pageX;
startY = e.touches[0].pageY;
e.preventDefault();//Stops the default behavior
}, false);
document.addEventListener("touchend", function(e){
endX = e.touches[0].pageX;
endY = e.touches[0].pageY;
e.preventDefault();//Stops the default behavior
}, false);

canvas.addEventListener('touchstart', function(e)
{
alert(e.changedTouches[0].pageX + " " + e.changedTouches[0].pageY);
}
canvas.addEventListener('touchend', function(e)
{
alert(e.changedTouches[0].pageX + " " + e.changedTouches[0].pageY);
}
Here's a good article about touching and gesturing on mobile phones:
http://www.sitepen.com/blog/2008/07/10/touching-and-gesturing-on-the-iphone/

Following solution preventing scroll when dragging AND at the same time usual scroll is working (when not dragging)
var scrollable = true;
var listener = function(e) {
if (! scrollable) {
e.preventDefault();
}
}
document.addEventListener('touchmove', listener, { passive:false });
onDragstartHandler() {
scrollable = false;
}
onDragendHandler(} {
scrollable = true;
}
Don't forget to bind onDragstartHandler and onDragendHandler to related elements

Safari iPad 1: how to disable zoom/centering on double-tap, but keep pinch zoom

I wonder if its possible to prevent double-tap-to-zoom and double-tap-to-center on a specific HTML element in Safari iOS (iPad 1) ?
Because my small HTML5 game forces users to make fast clicks (or taps), which are interpreted as double clicks, and when it happens - the page changes zoom and centers itself.
Detecting double clicks (like in this answer - Safari iPad : prevent zoom on double-tap) smells bad..
Wrong answer #1:
<meta name="viewport" content="width=device-width, minimum-scale=1.0, maximum-scale=1.0, user-scalable=no"> - does not suit my purposes, because it will block any zoom.
Wrong answer #2: maybe would .preventDefault() on click event alone be enough for that ? - Does not have any effect.

There's no other way than catching the events you want to prevent, and call preventDefault() on them, as you had already more or less figured out.
Indeed, some particular CSS properties / values may change the global site behavior (fixed width or fixed, for example), but you're not safe from changes to the OS (see fixedhandling change in iOS5), nor do these changes necessarily prevent all behavior (pinch might be off, but not double-tapping).
So, the best way to disable default behavior only for double-tapping is to take advantage of the count of touches iOS provides: if we have only one contact, then we're tapping. Two, this means we're pinching.
The following setup code provides that functionality:
var elm = document.body; // or some selection of the element you want to disable
var catcher = function(evt) {
if (evt.touches.length < 2)
evt.preventDefault();
};
elm.addEventListener('touchstart', catcher, true);
Demo on jsFiddle.
Note: the third parameter (true) to addEventListener means that we want to capture events, that is catch them all, even for our descendant children.

I am preventing doubletaps like this:
var doubleTouchStartTimestamp = 0;
$(document).bind("touchstart", function (event) {
var now = +(new Date());
if (doubleTouchStartTimestamp + 500 > now) {
event.preventDefault();
}
doubleTouchStartTimestamp = now;
});
The elegance lies within the fact, that no timeouts are needed. I only update a timestamp. It only gets compared on the next touchstart. Works for me on iOS 6.
Doubletaps further down the dom are not affected.
The same works without jQuery, as well:
var doubleTouchStartTimestamp = 0;
document.addEventListener("touchstart", function (event) {
var now = +(new Date());
if (doubleTouchStartTimestamp + 500 > now) {
event.preventDefault();
}
doubleTouchStartTimestamp = now;
});

I wrote a jQuery plugin for the same purpose - selectively disabling double-tap zoom on given page elements (in my case, navigation buttons to flip pages) I want to respond to every tap (including double-tap) as a normal click event, with no iOS "touch magic", no matter how fast the user clicks it.
To use it, just run something like $('.prev,.next').nodoubletapzoom(); on the elements you care for. The principle it uses is to listen for consecutive touchstart events on a node within 500ms, and running event.preventDefault() on the second, unless other touches are active at the same time. As that preventDefault consumes both touches, we also synthesize the two "missed" click events for the node, so your intended touch action happens as many times as the user intended.

Apple has a lot of tips with specialized tags for webkit (Safari). View Official Docs

What iOS version/Safari browser are you using? That site most definitely does not let you double-tap. I found some CSS but haven't had time to try it as I'm about to step out:
body {
-webkit-text-size-adjust:none;
margin:0px;
}
div{
clear:both!important;
display:block!important;
width:100%!important;
float:none!important;
margin:0!important;
padding:0!important;
}

You will need to implement a double tap function and preventDefault on the second tap. Here is some tested code that uses global variables that should get you started:
<button id="test1">Double Tap Me!</button>
<div id="test2">EMPTY</div>
var elm1 = document.getElementById('test1');
var elm2 = document.getElementById('test2');
var timeout;
var lastTap = 0;
elm1.addEventListener('touchend', function(event) {
var currentTime = new Date().getTime();
var tapLength = currentTime - lastTap;
clearTimeout(timeout);
if (tapLength < 500 && tapLength > 0) {
elm2.innerHTML = 'Double Tap';
event.preventDefault();
} else {
elm2.innerHTML = 'Single Tap';
timeout = setTimeout(function() {
elm2.innerHTML = 'Single Tap (timeout)';
clearTimeout(timeout);
}, 500);
}
lastTap = currentTime;
});
And a fiddle: http://jsfiddle.net/brettwp/J4djY/

JQuery approach to disable Double Tap Zoom in MVC4
To Disable the double tap (double mouse down) functionality on iOS 1+ you need to catch the touchStart Event and create an override to prevent the zoom.
// Using Single script.js and JQuery.Mobile-1.2.0 UI each page in MVC gets assigned JQuery through delegates so you don't have to do a full refresh of the page allowing you to take advantage of the data-prefetch which loads the page in the DOM when the app loads for the first time
$(document).delegate("#CashRegister", "pageinit", function () {
// To Disable 'Pinch to Zoom' Note: don't implement gester event handlers if you want to
//keep pinch to zoom functionality NOTE: i use this as my pageinit is a delegate of a page
this.addEventListener("gesturestart", gestureStart, false);
this.addEventListener("gesturechange", gestureChange, false);
this.addEventListener("gestureend", gestureEnd, false);
//handle each event by disabling the defaults
function gestureStart(event) {
event.preventDefault();
}
function gestureChange(event) {
event.preventDefault();
}
function gestureEnd(event) {
event.preventDefault();
}
//Recreate Double Tap and preventDefault on it
$(this).bind('touchstart', function preventZoom(e) {
// recreate the double tab functionality
var t2 = e.timeStamp
, t1 = $(this).data('lastTouch') || t2
, dt = t2 - t1
, fingers = e.originalEvent.touches.length;
$(this).data('lastTouch', t2);
if (!dt || dt > 500 || fingers > 1) return; // not double-tap
e.preventDefault(); // double tap - prevent the zoom
// also synthesize click events we just swallowed up
$(this).trigger('click').trigger('click');
});

Actually, .preventDefault() definitely does work... using jQuery:
var InputHandler = {
startEventType : isTouch ? "touchstart" : "mousedown"
}
$(selector).bind(InputHandler.startEventType, function(evnt) {
evnt.preventDefault();
});
Your problem with trying to prevent on .click() is that the browser isn't throwing a "click" element. Safari only fires a click to help simulate a click... But when there's a double tab, Safair doesn't through a "click" element. Your event handler for .click() doesn't ever fire, and therefore the .preventDefault() doesn't fire either.

JavaScript mapping touch events to mouse events

I'm using the YUI slider that operates with mouse move events. I want to make it respond to touchmove events (iPhone and Android). How can I produce a mouse move event when a touchmove event occurs? I'm hoping that just by adding some script at the top that touchmove events will get mapped to the mouse move events and I won't have to change anything with the slider.

I am sure this is what you want:
function touchHandler(event)
{
var touches = event.changedTouches,
first = touches[0],
type = "";
switch(event.type)
{
case "touchstart": type = "mousedown"; break;
case "touchmove": type = "mousemove"; break;
case "touchend": type = "mouseup"; break;
default: return;
}
// initMouseEvent(type, canBubble, cancelable, view, clickCount,
// screenX, screenY, clientX, clientY, ctrlKey,
// altKey, shiftKey, metaKey, button, relatedTarget);
var simulatedEvent = document.createEvent("MouseEvent");
simulatedEvent.initMouseEvent(type, true, true, window, 1,
first.screenX, first.screenY,
first.clientX, first.clientY, false,
false, false, false, 0/*left*/, null);
first.target.dispatchEvent(simulatedEvent);
event.preventDefault();
}
function init()
{
document.addEventListener("touchstart", touchHandler, true);
document.addEventListener("touchmove", touchHandler, true);
document.addEventListener("touchend", touchHandler, true);
document.addEventListener("touchcancel", touchHandler, true);
}
I've captured the touch events and then manually fired my own mouse events to match. Although the code isn't particularly general purpose as is, it should be trivial to adapt to most existing drag and drop libraries, and probably most existing mouse event code. Hopefully this idea will come in handy to people developing web applications for the iPhone.
Update:
In posting this, I noticed that calling preventDefault on all touch events will prevent links from working properly. The main reason to call preventDefault at all is to stop the phone from scrolling, and you can do that by calling it only on the touchmove callback. The only downside to doing it this way is that the iPhone will sometimes display its hover popup over the drag origin. If I discover a way to prevent that, I'll update this post.
Second Update:
I've found the CSS property to turn off the callout: -webkit-touch-callout.

I finally found a way to get this working using Mickey's solution but instead of his init function. Use the init function here.
function init() {
document.getElementById('filter_div').addEventListener("touchstart", touchHandler, true);
document.getElementById('filter_div').addEventListener("touchmove", touchHandler, true);
document.getElementById('filter_div').addEventListener("touchend", touchHandler, true);
document.getElementById('filter_div').addEventListener("touchcancel", touchHandler, true);
}
If you see 'filter_div' is the chart area where we have the chart range filter and only in that area do we want to rewrite our touch controls!
Thank you Mickey. It was a great solution.

Along the lines of #Mickey Shine's answer, Touch Punch provides mapping of touch events to click events. It's built to put this support into jQuery UI, but the code is informative.

For future users, who comeback here the following code might be used :
var eventMap = {};
(function(){
var eventReplacement = {
"mousedown": ["touchstart mousedown", "mousedown"],
"mouseup": ["touchend mouseup", "mouseup"],
"click": ["touchstart click", "click"],
"mousemove": ["touchmove mousemove", "mousemove"]
};
for (i in eventReplacement) {
if (typeof window["on" + eventReplacement[i][0]] == "object") {
eventMap[i] = eventReplacement[i][0];
}
else {
eventMap[i] = eventReplacement[i][1];
};
};
})();
And then in the events use like following :
$(".yourDiv").on(eventMap.mouseup, function(event) {
//your code
}

For making #Mickey's code work on Edge and internet explorer, add the following lines in .css of the element where you want the simulation to happen:
.areaWhereSimulationHappens {
overflow: hidden;
touch-action: none;
-ms-touch-action: none;
}
These lines prevent the default touch for edge and IE. But if you add it to the wrong element, then it also disables scroll (which happens by default on edge and IE on touch devices).

I just discovered this code resolving, i'm stuck on this situation in which I would like to put touch events and mouse event:
https://codepen.io/benstl/details/LYQjKvN
I supposed I have to add in te html the touchevents in the line :
div class="cube" onmousedown="grabOn(true)" onmouseup="grabOff()">
and on the javascript on :
document.addEventListener('mouseup', grabOff);
document.addEventListener('mousemove', handleMouseMove);
But there's also the grab function to link to either.