For some feature, I am working on mousemove event. The mousemove event listener is invoked a number of times within a single linear mouse gesture that is not required. I need to implement a custom event that will be invoked when the mouse stops its motion. I have a guess that it can be implemented on top of mousemove with some delay feature.
Please help me in this regard.
You're most of the way there:
function waitForMouseStop(callback) {
var timer;
function stoppedMoving(evt) {
document.onmousemove = null;
callback();
}
function moveHandler(evt) {
evt = evt || window.event;
if (timer) {
window.clearTimeout(timer);
}
timer = window.setTimeout(function() {
stoppedMoving(evt);
}, 500);
}
document.onmousemove = moveHandler;
}
waitForMouseStop(function() {
alert("Stopped");
});
Related
I'm hoping to get a GSAP animation to play ONCE when scrolling, but it seems if the user scrolls, let's say 20px on a long swipe on the touchpad or mouse wheel, it's playing 20 times. How can I limit this in the wheel event in Javascript.
I've added some code below as an example:
let isAnimating = false;
window.addEventListener('wheel', (event) => {
if (!isAnimating) {
isAnimating = true;
slideTimelines[0].play(0).then(() => {
isAnimating = false;
});
}
});
Actually you want to detect when scrolling is over. That way you fire it once for every scrolling dynamic. So the question is when a scroll is considered done, as there is no event for that. So let's say 250ms. Credit to this answer
function onwheelend() {
did_once = false;
}
var timeout_id;
var did_once = false;
window.addEventListener('wheel', (event) => {
clearTimeout(timeout_id);
timeout_id = setTimeout(onwheelend, 250);
if (!did_once) {
my_action()
did_once = true;
}
});
function my_action() {
console.log("once per wheel event")
}
<div style="height:30000px">keep scrolling</div>
I have an Iiyama PCAP Multi Touch Monitor on which I want to listen for the mousemove (touchmove) event. But this event is never triggered on this monitor. Is there a chance to get the following working, or any other idea for what I must listen on such devices?
$(this).on("mousemove", function () {
hasMoved = true;
lastMove = (new Date()).getTime();
if (isidle) {
onactive.call(this);
isidle = false;
}
});
You tried the touche-events?
$(this).on("touchmove", function () {
hasMoved = true;
lastMove = (new Date()).getTime();
if (isidle) {
onactive.call(this);
isidle = false;
}
});
More touch-events here: touch events
Here is my code:
var mouseDown = false;
document.body.onmousedown = function() {
console.log("MOUSE DOWN");
mouseDown = true;
increaseRad();
}
document.body.onmouseup = function() {
console.log("MOUSE UP");
mouseDown = false;
}
function increaseRad(){
rad = 0;
while(mouseDown){
console.log("mouse is still down");
rad++;
console.log(rad)
}
}
When I press down, increaseRad is run, but the while loop inside never ends.
Any idea why?
The problem here is that your code runs as a blocking loop.
while(mouseDown){
console.log("mouse is still down");
rad++;
console.log(rad)
}
The browser evaluates Javascript in a single thread and this loop will never pause to let the browser process those event handlers.
Instead you can use just use asynchronous functions to listen for mousedown events, then start a timer. If the mouse is still down when the timer finishes, then you can count it as a long click.
var mouseIsDown = false;
window.addEventListener('mousedown', function() {
mouseIsDown = true;
setTimeout(function() {
if(mouseIsDown) {
// mouse was held down for > 2 seconds
}
}, 2000);
});
window.addEventListener('mouseup', function() {
mouseIsDown = false;
});
These asynchronous actions (addEventListener, setTimeout) won't block the main thread.
If you click serveral times in a row, you get a wrong click & hold. Better solution is...
var mouseIsDown = false;
var idTimeout;
window.addEventListener('mousedown', function() {
mouseIsDown = true;
idTimeout = setTimeout(function() {
if(mouseIsDown) {
// mouse was held down for > 2 seconds
}
}, 2000);
});
window.addEventListener('mouseup', function() {
clearTimeout(idTimeout);
mouseIsDown = false;
});
I am struggling to understand how a custom event type is linked to a specific user action/trigger. All documentation seems to dispatch the event without any user interaction.
In the following example I want the event to be dispatched once a user has been hovering on the element for 3 seconds.
var img = document.createElement('img');img.src = 'http://placehold.it/100x100';
document.body.appendChild(img)
var event = new CustomEvent("hoveredforthreeseconds");
img.addEventListener('hoveredforthreeseconds', function(e) { console.log(e.type)}, true);
var thetrigger = function (element, event) {
var timeout = null;
element.addEventListener('mouseover',function() {
timeout = setTimeout(element.dispatchEvent(event), 3000);
},true);
element.addEventListener('mouseout', function() {
clearTimeout(timeout);
},true);
};
I have a trigger but no logical way of connecting it to the event.
I was thinking about creating an object called CustomEventTrigger which is essentially CustomEvent but has a third parameter for the trigger and also creating a method called addCustomEventListener, which works the same as addEventListener but when initialised it then passes the target Element to the custom event trigger which then dispatches the event when it's instructed to.
Custom events have to be triggered programatically through dispatchEvent, they are not fired by the DOM. You will always need to explictly call them in your code, such as in response to a user-generated event such as onmouseover, or a change of state such as onload.
You're very close to a working implementation, however you're immediately invoking dispatchEvent in your setTimeout. If you save it into a closure (as below) you can invoke dispatchEvent while passing your element after setTimeout has finished the timeout.
It's also good practice to declare your variables at the top of a file, to avoid possible scope issues.
var img = document.createElement('img'), timeout, event, thetrigger;
img.src = 'http://placehold.it/100x100';
document.body.appendChild(img);
img.addEventListener("hoveredForThreeSeconds", afterHover, false);
thetrigger = function (element, event) {
timeout = null;
element.addEventListener('mouseover',function() {
timeout = setTimeout(function(){ element.dispatchEvent(event) }, 3000);
},true);
element.addEventListener('mouseout', function() {
clearTimeout(timeout);
},true);
};
function afterHover(e) {
console.log("Event is called: " + e.type);
}
event = new CustomEvent("hoveredForThreeSeconds");
thetrigger(img, event);
I have created a method called addCustomEventListener, which works the same as addEventListener but when initialised passes the target Element to the custom event trigger which dispatches the event when it says, so in this case it only dispatches if the timeout reaches 3 seconds.
var img = document.getElementById('img');
window.mouseover3000 = new CustomEvent('mouseover3000', {
detail: {
trigger: function(element, type) {
timeout = null;
element.addEventListener('mouseover', function() {
timeout = setTimeout(function() {
element.dispatchEvent(window[type])
}, 3000);
}, false);
element.addEventListener('mouseout', function() {
clearTimeout(timeout);
}, false)
}
}
});
window.tripleclick = new CustomEvent('tripleclick', {
detail: {
trigger: function(element, type) {
element.addEventListener('click', function(e) {
if(e.detail ===3){
element.dispatchEvent(window[type])
}
}, false);
}
}
});
EventTarget.prototype.addCustomEventListener = function(type, listener, useCapture, wantsUntrusted) {
this.addEventListener(type, listener, useCapture, wantsUntrusted);
window[type].detail.trigger(this, type);
}
var eventTypeImage = function(e) {
this.src = "http://placehold.it/200x200?text=" + e.type;
}
img.addEventListener('mouseout', eventTypeImage, false);
img.addEventListener('mouseover', eventTypeImage, false);
img.addCustomEventListener('mouseover3000', eventTypeImage, false);
img.addCustomEventListener('tripleclick', eventTypeImage, false);
<img id="img" src="http://placehold.it/200x200?text=No+hover" ;/>
I think this could be useful to others so please feel free to improve on this.
I have an element on my page that I need to attach onclick and ondblclick event handlers to. When a single click happens, it should do something different than a double-click. When I first started trying to make this work, my head started spinning. Obviously, onclick will always fire when you double-click. So I tried using a timeout-based structure like this...
window.onload = function() {
var timer;
var el = document.getElementById('testButton');
el.onclick = function() {
timer = setTimeout(function() { alert('Single'); }, 150);
}
el.ondblclick = function() {
clearTimeout(timer);
alert('Double');
}
}
But I got inconsistent results (using IE8). It would work properly alot of times, but sometimes I would get the "Single" alert two times.
Has anybody done this before? Is there a more effective way?
Like Matt, I had a much better experience when I increased the timeout value slightly. Also, to mitigate the problem of single click firing twice (which I was unable to reproduce with the higher timer anyway), I added a line to the single click handler:
el.onclick = function() {
if (timer) clearTimeout(timer);
timer = setTimeout(function() { alert('Single'); }, 250);
}
This way, if click is already set to fire, it will clear itself to avoid duplicate 'Single' alerts.
If you're getting 2 alerts, it would seem your threshold for detecing a double click is too small. Try increasing 150 to 300ms.
Also - I'm not sure that you are guaranteed the order in which click and dblclick are fired. So, when your dblclick gets fired, it clears out the first click event, but if it fires before the second 'click' event, this second event will still fire on its own, and you'll end up with both a double click event firing and a single click event firing.
I see two possible solutions to this potential problem:
1) Set another timeout for actually firing the double-click event. Mark in your code that the double click event is about to fire. Then, when the 2nd 'single click' event fires, it can check on this state, and say "oops, dbl click pending, so I'll do nothing"
2) The second option is to swap your target functions out based on click events. It might look something like this:
window.onload = function() {
var timer;
var el = document.getElementById('testButton');
var firing = false;
var singleClick = function(){
alert('Single');
};
var doubleClick = function(){
alert('Double');
};
var firingFunc = singleClick;
el.onclick = function() {
// Detect the 2nd single click event, so we can stop it
if(firing)
return;
firing = true;
timer = setTimeout(function() {
firingFunc();
// Always revert back to singleClick firing function
firingFunc = singleClick;
firing = false;
}, 150);
}
el.ondblclick = function() {
firingFunc = doubleClick;
// Now, when the original timeout of your single click finishes,
// firingFunc will be pointing to your doubleClick handler
}
}
Basically what is happening here is you let the original timeout you set continue. It will always call firingFunc(); The only thing that changes is what firingFunc() is actually pointing to. Once the double click is detected, it sets it to doubleClick. And then we always revert back to singleClick once the timeout expires.
We also have a "firing" variable in there so we know to intercept the 2nd single click event.
Another alternative is to ignore dblclick events entirely, and just detect it with the single clicks and the timer:
window.onload = function() {
var timer;
var el = document.getElementById('testButton');
var firing = false;
var singleClick = function(){
alert('Single');
};
var doubleClick = function(){
alert('Double');
};
var firingFunc = singleClick;
el.onclick = function() {
// Detect the 2nd single click event, so we can set it to doubleClick
if(firing){
firingFunc = doubleClick;
return;
}
firing = true;
timer = setTimeout(function() {
firingFunc();
// Always revert back to singleClick firing function
firingFunc = singleClick;
firing = false;
}, 150);
}
}
This is untested :)
Simple:
obj.onclick=function(e){
if(obj.timerID){
clearTimeout(obj.timerID);
obj.timerID=null;
console.log("double")
}
else{
obj.timerID=setTimeout(function(){
obj.timerID=null;
console.log("single")
},250)}
}//onclick
Small fix
if(typeof dbtimer != "undefined"){
dbclearTimeout(timer);
timer = undefined;
//double click
}else{
dbtimer = setTimeout(function() {
dbtimer = undefined;
//single click
}, 250);
}
, cellclick :
function(){
setTimeout(function(){
if (this.dblclickchk) return;
setTimeout(function(){
click event......
},100);
},500);
}
, celldblclick :
function(){
setTimeout(function(){
this.dblclickchk = true;
setTimeout(function(){
dblclick event.....
},100);
setTimeout(function(){
this.dblclickchk = false;
},3000);
},1);
}
I found by accident that this works (it's a case with Bing Maps):
pushpin.clickTimer = -1;
Microsoft.Maps.Events.addHandler(pushpin, 'click', (pushpin) {
return function () {
if (pushpin.clickTimer == -1) {
pushpin.clickTimer = setTimeout((function (pushpin) {
return function () {
alert('Single Clic!');
pushpin.clickTimer = -1;
// single click handle code here
}
}(pushpin)), 300);
}
}
}(pushpin)));
Microsoft.Maps.Events.addHandler(pushpin, 'dblclick', (function (pushpin) {
return function () {
alert('Double Click!');
clearTimeout(pushpin.clickTimer);
pushpin.clickTimer = -1;
// double click handle here
}
}(pushpin)));
It looks like the click event masks the dblclick event, and this usage is clearing it when we add a timeout. So, hopefully, this will work also with non Bing Maps cases, after a slight adaptation, but I didn't try it.