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I'm messing around with touch events on a touch slider and I keep getting the following error:
Ignored attempt to cancel a touchmove event with cancelable=false,
for example because scrolling is in progress and cannot be
interrupted.
I'm not sure what is causing this problem, I am new to working with touch events and can't seem to fix this problem.
Here is the code handling the touch event:
Slider.prototype.isSwipe = function(threshold) {
return Math.abs(deltaX) > Math.max(threshold, Math.abs(deltaY));
}
Slider.prototype.touchStart = function(e) {
if (this._isSliding) return false;
touchMoving = true;
deltaX = deltaY = 0;
if (e.originalEvent.touches.length === 1) {
startX = e.originalEvent.touches[0].pageX;
startY = e.originalEvent.touches[0].pageY;
this._$slider.on('touchmove touchcancel', this.touchMove.bind(this)).one('touchend', this.touchEnd.bind(this));
isFlick = true;
window.setTimeout(function() {
isFlick = false;
}, flickTimeout);
}
}
Slider.prototype.touchMove = function(e) {
deltaX = startX - e.originalEvent.touches[0].pageX;
deltaY = startY - e.originalEvent.touches[0].pageY;
if(this.isSwipe(swipeThreshold)) {
e.preventDefault();
e.stopPropagation();
swiping = true;
}
if(swiping) {
this.slide(deltaX / this._sliderWidth, true)
}
}
Slider.prototype.touchEnd = function(e) {
var threshold = isFlick ? swipeThreshold : this._sliderWidth / 2;
if (this.isSwipe(threshold)) {
deltaX < 0 ? this.prev() : this.next();
}
else {
this.slide(0, !deltaX);
}
swiping = false;
this._$slider.off('touchmove', this.touchMove).one(transitionend, $.proxy(function() {
this.slide(0, true);
touchMoving = false;
}, this));
}
You can find the actual slider here at this pen.
If you swipe through fast enough it will throw the error and sometimes get stuck in the middle of a swipe. Still can't wrap my head around why it is not working. Any help/insight would be greatly appreciated. Not sure what I am doing wrong.
The event must be cancelable. Adding an if statement solves this issue.
if (e.cancelable) {
e.preventDefault();
}
In your code you should put it here:
if (this.isSwipe(swipeThreshold) && e.cancelable) {
e.preventDefault();
e.stopPropagation();
swiping = true;
}
I know this is an old post but I had a lot of issues trying to solve this and I finally did so I wanted to share.
My issue was that I was adding an event listener within the ontouchstart and removing it in the ontouchend functions - something like this
function onTouchStart() {
window.addEventListener("touchmove", handleTouchMove, {
passive: false
});
}
function onTouchEnd() {
window.removeEventListener("touchmove", handleTouchMove, {
passive: true
});
}
function handleTouchMove(e) {
e.preventDefault();
}
For some reason adding it removing it like this was causing this issue of the event randomly not being cancelable. So to solve this I kept the listener active and toggled a boolean on whether or not it should prevent the event - something like this:
let stopScrolling = false;
window.addEventListener("touchmove", handleTouchMove, {
passive: false
});
function handleTouchMove(e) {
if (!stopScrolling) {
return;
}
e.preventDefault();
}
function onTouchStart() {
stopScrolling = true;
}
function onTouchEnd() {
stopScrolling = false;
}
I was actually using React so my solution involved setting state, but I've simplified it for a more generic solution. Hopefully this helps someone!
I had this problem and all I had to do is return true from touchend and the warning went away.
Calling preventDefault on touchmove while you're actively scrolling is not working in Chrome. To prevent performance issues, you cannot interrupt a scroll.
Try to call preventDefault() from touchstart and everything should be ok.
Please remove e.preventDefault(), because event.cancelable of touchmove is false.
So you can't call this method.
If it is an image, you can just set 'touch-action' to none in css.
I am currently developing a javascript game, and I can't get touch controls to work on mobile devices. It is a simple game, in which you can press Up arrow to jump, or Down arrow to roll.
I would like to also implement the touch controls, so the touch/hold of the left side of the display would make the character roll, and by touching/holding the right side of the screen, the character jumps.
This is the code that is working for me for the Up and Down arrow:
var KEY_CODES = {
38: 'up',
40: 'down'
};
var KEY_STATUS = {};
for (var code in KEY_CODES) {
if (KEY_CODES.hasOwnProperty(code)) {
KEY_STATUS[KEY_CODES[code]] = false;
}
}
document.onkeydown = function(e) {
var keyCode = (e.keyCode) ? e.keyCode : e.charCode;
if (KEY_CODES[keyCode]) {
e.preventDefault();
KEY_STATUS[KEY_CODES[keyCode]] = true;
}
};
document.onkeyup = function(e) {
var keyCode = (e.keyCode) ? e.keyCode : e.charCode;
if (KEY_CODES[keyCode]) {
e.preventDefault();
KEY_STATUS[KEY_CODES[keyCode]] = false;
}
};
And then I can make tha character to do things by doing:
if (KEY_STATUS.up) { stuff and things }
Any advices, hints, recommendations or possible code scraps that might help me? Thanks in advance!
You should be able to use touch events. In many cases you can use the same functions that you wrote for the keypresses, or you can write them separately. Here's an example
var touchedElement = document.getElementById("myElementToBeTouched");
touchedElement.addEventListener("touchstart", funcTouchStart, false);
touchedElement.addEventListener("touchend", funcTouchEnd, false);
touchedElement.addEventListener("touchmove", funcTouchMove, false);
function funcTouchStart(e) {
//code to do what you want like set variables and check where on screen touch happened
var touches = e.changedTouches; //gets array of touch points, to get position
}
function funcTouchEnd(e) {
//code
}
function funcTouchMove(e) {
//code
}
To make them respond to left or right screen, you could use the touches[i].pageX that comes with these events and set the action to happen only if in the 25% of the screen from touches[i].pageX = 0 (for left) or last 25% to where the touches[i].pageX = width of screen/viewport.
This is not a complete working example but I hope its enough to give you an idea of what you could do. If you need more help with these events, try looking at one of MDN examples such as:
https://developer.mozilla.org/en-US/docs/Web/Guide/Events/Touch_events
I have some code which changes the class of a table. On a phone, sometimes the table will be too wide for the screen and the user will drag/scroll about to see the contents. However, when they touch and drag the table around, it triggers touchend on every drag.
How do I test to see whether the touchend came as a result of a touch-drag? I tried tracking dragstart and dragend but I couldn't get that to work and it seems an inelegant approach. Is there something I could add to below which would essentially determine, "Did this touchend come at the end of a drag?"
$("#resultTable").on("touchend","#resultTable td",function(){
$(this).toggleClass('stay');
});
My thanks in advance for your help.
PS - using latest jquery, and while a regular click works, it is very slow in comparison to touchend.
Use two listeners:
First set a variable to false:
var dragging = false;
Then ontouchmove set dragging to true
$("body").on("touchmove", function(){
dragging = true;
});
Then on drag complete, check to see if dragging is true, and if so count it as a dragged touch:
$("body").on("touchend", function(){
if (dragging)
return;
// wasn't a drag, just a tap
// more code here
});
The touch end will still fire, but will terminate itself before your tap script is run.
To ensure the next time you touch it isn't already set as dragged, reset it back to false on touch down.
$("body").on("touchstart", function(){
dragging = false;
});
Looks like one solution to my problem is found here:
http://alxgbsn.co.uk/2011/08/16/event-delegation-for-touch-events-in-javascript/
This bit of code detects any move after touchstart in order to abort tap behavior after tapend.
var tapArea, moved, startX, startY;
tapArea = document.querySelector('#list'); //element to delegate
moved = false; //flags if the finger has moved
startX = 0; //starting x coordinate
startY = 0; //starting y coordinate
//touchstart
tapArea.ontouchstart = function(e) {
moved = false;
startX = e.touches[0].clientX;
startY = e.touches[0].clientY;
};
//touchmove
tapArea.ontouchmove = function(e) {
//if finger moves more than 10px flag to cancel
//code.google.com/mobile/articles/fast_buttons.html
if (Math.abs(e.touches[0].clientX - startX) > 10 ||
Math.abs(e.touches[0].clientY - startY) > 10) {
moved = true;
}
};
//touchend
tapArea.ontouchend = function(e) {
e.preventDefault();
//get element from touch point
var element = e.changedTouches[0].target;
//if the element is a text node, get its parent.
if (element.nodeType === 3) {
element = element.parentNode;
}
if (!moved) {
//check for the element type you want to capture
if (element.tagName.toLowerCase() === 'label') {
alert('tap');
}
}
};
//don't forget about touchcancel!
tapArea.ontouchcancel = function(e) {
//reset variables
moved = false;
startX = 0;
startY = 0;
};
More here:
https://developers.google.com/mobile/articles/fast_buttons
I would say you can't tell the difference when the user drags to see more content or drag the element arround. I think you should change the approach. You could detect if it's a mobile device and then draw a switch that will enable/disable the movement of the element.
To shorten the solution of #lededge, this might help.
$("body").on("touchmove", function(){
dragging = true;
}).on("touchend", function(){
if (dragging)
return;
}).on("touchstart", function(){
dragging = false;
});
I created a Fiddle to demonstrate my situation.
I want to not fire the click event when the user is panning--only if it's just a simple click. I've experimented with different placements of .off() and .on() to no avail.
Thanks in advance for your help.
http://jsfiddle.net/Waxen/syTKq/3/
Updated your fiddle to do what you want. I put the re-binding of the event in a timeout so it wouldn't trigger immediately, and adjusted the mousemove to
In on click event, you can detect whether mouse was pressed DOWN or UP. So let's analyse:
DRAG:
mouse down
mosue position changes
mouse up
CLICK:
mouse down
mouse up
You see - the difference is changed mouse position. You can record click coordinate in mouse down and then compare it when muse goes back up. If it is within some treshold, the action was a click.
The only way to tell between a "click" and a "pan" would be the time the mouse has spent held down. You could create a Date in the mousedown, then another in the mouseup, and only fire your click (zoom) event if the difference between the two dates is greater than some threshold (i would guess 1/10 of a second, but you may want to experiment)
I added a "panning" bool for a solution to your problem:
see http://jsfiddle.net/syTKq/4/
Basically, if the user has mousedown and mousemove, then panning is true. once mouseup panning is false. if just mousedown, panning is false, therefore zoom.
This solution solves your problem:
var bClicking = false,
moved = false;;
var previousX, previousY;
var $slider = $('#slider'),
$wrapper = $slider.find('li.wrapper'),
$img = $slider.find('img.foo');
$img.on('click', function()
{
if(!moved)
{
doZoom();
}
});
$wrapper.mousedown(function(e) {
e.preventDefault();
previousX = e.clientX;
previousY = e.clientY;
bClicking = true;
moved = false;
});
$(document).mouseup(function(e) {
bClicking = false;
});
$wrapper.mousemove(function(e) {
if (bClicking)
{
moved = true;
var directionX = (previousX - e.clientX) > 0 ? 1 : -1;
var directionY = (previousY - e.clientY) > 0 ? 1 : -1;
$(this).scrollLeft($(this).scrollLeft() + 10 * directionX);
$(this).scrollTop($(this).scrollTop() + 10 * directionY);
previousX = e.clientX;
previousY = e.clientY;
}
});
function doZoom() {
$img.animate({
height: '+=300',
width: '+=300'
}, 500, function() {
//animation complete
});
}
Basically, it calls doZoom() only when the mouse has not moved between the mousedown and the mouseup events.
You can use the mousemove/mousedown events to set a flag that can be used in the click event handler to determine if the user was clicking or panning. Something like:
//set a flag for the click event to check
var isClick = false;
//bind to `mousedown` event to set the `isClick` flag to true
$(document).on('mousedown', function (event) {
isClick = true;
//bind to `mousemove` event to set the `isClick` flag to false (since it's not a drag
}).on('mousemove', function () {
isClick = false;
//bind to `click` event, check to see if the `isClick` flag is set to true, if so then this is a click, otherwise this is a drag
}).on('click', function () {
if (isClick) {
console.log('click');
} else {
console.log('drag');
}
});
Here is a demo: http://jsfiddle.net/SU7Ef/
Is there a way to detect if a mouse button is currently down in JavaScript?
I know about the "mousedown" event, but that's not what I need. Some time AFTER the mouse button is pressed, I want to be able to detect if it is still pressed down.
Is this possible?
Regarding Pax' solution: it doesn't work if user clicks more than one button intentionally or accidentally. Don't ask me how I know :-(.
The correct code should be like that:
var mouseDown = 0;
document.body.onmousedown = function() {
++mouseDown;
}
document.body.onmouseup = function() {
--mouseDown;
}
With the test like this:
if(mouseDown){
// crikey! isn't she a beauty?
}
If you want to know what button is pressed, be prepared to make mouseDown an array of counters and count them separately for separate buttons:
// let's pretend that a mouse doesn't have more than 9 buttons
var mouseDown = [0, 0, 0, 0, 0, 0, 0, 0, 0],
mouseDownCount = 0;
document.body.onmousedown = function(evt) {
++mouseDown[evt.button];
++mouseDownCount;
}
document.body.onmouseup = function(evt) {
--mouseDown[evt.button];
--mouseDownCount;
}
Now you can check what buttons were pressed exactly:
if(mouseDownCount){
// alright, let's lift the little bugger up!
for(var i = 0; i < mouseDown.length; ++i){
if(mouseDown[i]){
// we found it right there!
}
}
}
Now be warned that the code above would work only for standard-compliant browsers that pass you a button number starting from 0 and up. IE uses a bit mask of currently pressed buttons:
0 for "nothing is pressed"
1 for left
2 for right
4 for middle
and any combination of above, e.g., 5 for left + middle
So adjust your code accordingly! I leave it as an exercise.
And remember: IE uses a global event object called … "event".
Incidentally IE has a feature useful in your case: when other browsers send "button" only for mouse button events (onclick, onmousedown, and onmouseup), IE sends it with onmousemove too. So you can start listening for onmousemove when you need to know the button state, and check for evt.button as soon as you got it — now you know what mouse buttons were pressed:
// for IE only!
document.body.onmousemove = function(){
if(event.button){
// aha! we caught a feisty little sheila!
}
};
Of course you get nothing if she plays dead and not moving.
Relevant links:
MouseEvent's button (DOM 2)
MSDN's button
Update #1: I don't know why I carried over the document.body-style of code. It will be better to attach event handlers directly to the document.
This is an old question, and the answers here seem to mostly advocate for using mousedown and mouseup to keep track of whether a button is pressed. But as others have pointed out, mouseup will only fire when performed within the browser, which can lead to losing track of the button state.
However, MouseEvent (now) indicates which buttons are currently pushed:
For all modern browsers (including Safari v11.1+ [v11.3+ on iOS]), use MouseEvent.buttons
For Safari < 11.1 (11.3 on iOS), use MouseEvent.which (buttons will be undefined for Safari) Note: which uses different numbers from buttons for Right and Middle clicks.
When registered on document, mousemove will fire immediately as soon as the cursor reenters the browser, so if the user releases outside then the state will be updated as soon as they mouse back inside.
A simple implementation might look like:
var primaryMouseButtonDown = false;
function setPrimaryButtonState(e) {
var flags = e.buttons !== undefined ? e.buttons : e.which;
primaryMouseButtonDown = (flags & 1) === 1;
}
document.addEventListener("mousedown", setPrimaryButtonState);
document.addEventListener("mousemove", setPrimaryButtonState);
document.addEventListener("mouseup", setPrimaryButtonState);
That code tracks the state of the primary mouse button (typically the left), ignoring the state of other mouse buttons.
If more complicated scenarios are required (different buttons/multiple buttons/control keys), check out the MouseEvent docs.
I think the best approach to this is to keep your own record of the mouse button state, as follows:
var mouseDown = 0;
document.body.onmousedown = function() {
mouseDown = 1;
}
document.body.onmouseup = function() {
mouseDown = 0;
}
and then, later in your code:
if (mouseDown == 1) {
// the mouse is down, do what you have to do.
}
the solution isn't good.
one could "mousedown" on the document, then "mouseup" outside the browser, and on this case the browser would still be thinking the mouse is down.
the only good solution is using IE.event object.
I know this is an old post, but I thought the tracking of mouse button using mouse up/down felt a bit clunky, so I found an alternative that may appeal to some.
<style>
div.myDiv:active {
cursor: default;
}
</style>
<script>
function handleMove( div ) {
var style = getComputedStyle( div );
if (style.getPropertyValue('cursor') == 'default')
{
// You're down and moving here!
}
}
</script>
<div class='myDiv' onmousemove='handleMove(this);'>Click and drag me!</div>
The :active selector handles the mouse click much better than mouse up/down, you just need a way of reading that state in the onmousemove event. For that I needed to cheat and relied on the fact that the default cursor is "auto" and I just change it to "default", which is what auto selects by default.
You can use anything in the object that is returned by getComputedStyle that you can use as a flag without upsetting the look of your page e.g. border-color.
I would have liked to set my own user defined style in the :active section, but I couldn't get that to work. It would be better if it's possible.
If you're working within a complex page with existing mouse event handlers, I'd recommend handling the event on capture (instead of bubble). To do this, just set the 3rd parameter of addEventListener to true.
Additionally, you may want to check for event.which to ensure you're handling actual user interaction and not mouse events, e.g. elem.dispatchEvent(new Event('mousedown')).
var isMouseDown = false;
document.addEventListener('mousedown', function(event) {
if ( event.which ) isMouseDown = true;
}, true);
document.addEventListener('mouseup', function(event) {
if ( event.which ) isMouseDown = false;
}, true);
Add the handler to document (or window) instead of document.body is important b/c it ensures that mouseup events outside of the window are still recorded.
The following snippet will attempt to execute the "doStuff" function 2 seconds after the mouseDown event occurs in document.body. If the user lifts up the button, the mouseUp event will occur and cancel the delayed execution.
I'd advise using some method for cross-browser event attachment - setting the mousedown and mouseup properties explicitly was done to simplify the example.
function doStuff() {
// does something when mouse is down in body for longer than 2 seconds
}
var mousedownTimeout;
document.body.onmousedown = function() {
mousedownTimeout = window.setTimeout(doStuff, 2000);
}
document.body.onmouseup = function() {
window.clearTimeout(mousedownTimeout);
}
In case someone else runs into this, you can use .matches with the :active selector:
function mouseDown() {
return document.body.matches(":active");
}
Using the MouseEvent api, to check the pressed button, if any:
// Mouse buttons
document.addEventListener('mousedown', e => console.log(e.buttons))
// Keyboard keys
document.addEventListener('keydown', e => console.log(e.key))
Return:
A number representing one or more buttons. For more than one button
pressed simultaneously, the values are combined (e.g., 3 is primary +
secondary).
0 : No button or un-initialized
1 : Primary button (usually the left button)
2 : Secondary button (usually the right button)
4 : Auxilary button (usually the mouse wheel button or middle button)
8 : 4th button (typically the "Browser Back" button)
16 : 5th button (typically the "Browser Forward" button)
You can combine #Pax and my answers to also get the duration that the mouse has been down for:
var mousedownTimeout,
mousedown = 0;
document.body.onmousedown = function() {
mousedown = 0;
window.clearInterval(mousedownTimeout);
mousedownTimeout = window.setInterval(function() { mousedown += 200 }, 200);
}
document.body.onmouseup = function() {
mousedown = 0;
window.clearInterval(mousedownTimeout);
}
Then later:
if (mousedown >= 2000) {
// do something if the mousebutton has been down for at least 2 seconds
}
You need to handle the MouseDown and MouseUp and set some flag or something to track it "later down the road"... :(
Short and sweet
I'm not sure why none of the previous answers worked for me, but I came up with this solution during a eureka moment. It not only works, but it is also most elegant:
Add to body tag:
onmouseup="down=0;" onmousedown="down=1;"
Then test and execute myfunction() if down equals 1:
onmousemove="if (down==1) myfunction();"
Using jQuery, the following solution handles even the "drag off the page then release case".
$(document).mousedown(function(e) {
mouseDown = true;
}).mouseup(function(e) {
mouseDown = false;
}).mouseleave(function(e) {
mouseDown = false;
});
I don't know how it handles multiple mouse buttons.
If there were a way to start the click outside the window, then bring the mouse into the window, then this would probably not work properly there either.
As said #Jack, when mouseup happens outside of browser window, we are not aware of it...
This code (almost) worked for me:
window.addEventListener('mouseup', mouseUpHandler, false);
window.addEventListener('mousedown', mouseDownHandler, false);
Unfortunately, I won't get the mouseup event in one of those cases:
user simultaneously presses a keyboard key and a mouse button, releases mouse button outside of browser window then releases key.
user presses two mouse buttons simultaneously, releases one mouse button then the other one, both outside of browser window.
var mousedown = 0;
$(function(){
document.onmousedown = function(e){
mousedown = mousedown | getWindowStyleButton(e);
e = e || window.event;
console.log("Button: " + e.button + " Which: " + e.which + " MouseDown: " + mousedown);
}
document.onmouseup = function(e){
mousedown = mousedown ^ getWindowStyleButton(e);
e = e || window.event;
console.log("Button: " + e.button + " Which: " + e.which + " MouseDown: " + mousedown);
}
document.oncontextmenu = function(e){
// to suppress oncontextmenu because it blocks
// a mouseup when two buttons are pressed and
// the right-mouse button is released before
// the other button.
return false;
}
});
function getWindowStyleButton(e){
var button = 0;
if (e) {
if (e.button === 0) button = 1;
else if (e.button === 1) button = 4;
else if (e.button === 2) button = 2;
}else if (window.event){
button = window.event.button;
}
return button;
}
this cross-browser version works fine for me.
Below jQuery example, when mouse is over $('.element'), color is changing depending on which mouse button is pressed.
var clicableArea = {
init: function () {
var self = this;
('.element').mouseover(function (e) {
self.handlemouseClick(e, $(this));
}).mousedown(function (e) {
self.handlemouseClick(e, $(this));
});
},
handlemouseClick: function (e, element) {
if (e.buttons === 1) {//left button
element.css('background', '#f00');
}
if (e.buttons === 2) { //right buttom
element.css('background', 'none');
}
}
};
$(document).ready(function () {
clicableArea.init();
});
Well, you can't check if it's down after the event, but you can check if it's Up... If it's up.. it means that no longer is down :P lol
So the user presses the button down (onMouseDown event) ... and after that, you check if is up (onMouseUp). While it's not up, you can do what you need.