I am hoping to track the position of the mouse cursor, periodically every t mseconds. So essentially, when a page loads - this tracker should start and for (say) every 100 m
Here’s a combination of the two requirements: track the mouse position, every 100 milliseconds:
var period = 100,
tracking;
window.addEventListener("mousemove", function(e) {
if (!tracking) {
return;
}
console.log("mouse location:", e.clientX, e.clientY)
schedule();
});
schedule();
function schedule() {
tracking = false;
setTimeout(function() {
tracking = true;
}, period);
}
This tracks & acts on the mouse position, but only every period milliseconds.
Just a simplified version of @T.J. Crowder and @RegarBoy's answers.
Less is more in my opinion.
Check out onmousemove event for more info about the event.
There's a new value of posX
and posY
every time the mouse moves according to the horizontal and vertical coordinates.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Example Mouse Tracker</title>
<style>
body {height: 3000px;}
.dot {width: 2px;height: 2px;background-color: black;position: absolute;}
</style>
</head>
<body>
<p>Mouse tracker</p>
<script>
onmousemove = function(e){
//Logging purposes
console.log("mouse location:", e.clientX, e.clientY);
//meat and potatoes of the snippet
var pos = e;
var dot;
dot = document.createElement('div');
dot.className = "dot";
dot.style.left = pos.x + "px";
dot.style.top = pos.y + "px";
document.body.appendChild(dot);
}
</script>
</body>
</html>
What I think that he only wants to know the X/Y positions of cursor than why answer is that complicated.
// Getting 'Info' div in js hands
var info = document.getElementById('info');
// Creating function that will tell the position of cursor
// PageX and PageY will getting position values and show them in P
function tellPos(p){
info.innerHTML = 'Position X : ' + p.pageX + '<br />Position Y : ' + p.pageY;
}
addEventListener('mousemove', tellPos, false);
* {
padding: 0:
margin: 0;
/*transition: 0.2s all ease;*/
}
#info {
position: absolute;
top: 10px;
right: 10px;
background-color: black;
color: white;
padding: 25px 50px;
}
<!DOCTYPE html>
<html>
<body>
<div id='info'></div>
</body>
</html>
I believe that we are overthinking this,
function mouse_position(e)
{
//do stuff
}
<body onmousemove="mouse_position(event)"></body>
The mouse's position is reported on the event
object received by a handler for the mousemove
event, which you can attach to the window (the event bubbles):
(function() {
document.onmousemove = handleMouseMove;
function handleMouseMove(event) {
var eventDoc, doc, body;
event = event || window.event; // IE-ism
// If pageX/Y aren't available and clientX/Y are,
// calculate pageX/Y - logic taken from jQuery.
// (This is to support old IE)
if (event.pageX == null && event.clientX != null) {
eventDoc = (event.target && event.target.ownerDocument) || document;
doc = eventDoc.documentElement;
body = eventDoc.body;
event.pageX = event.clientX +
(doc && doc.scrollLeft || body && body.scrollLeft || 0) -
(doc && doc.clientLeft || body && body.clientLeft || 0);
event.pageY = event.clientY +
(doc && doc.scrollTop || body && body.scrollTop || 0) -
(doc && doc.clientTop || body && body.clientTop || 0 );
}
// Use event.pageX / event.pageY here
}
})();
(Note that the body of that if
will only run on old IE.)
Example of the above in action - it draws dots as you drag your mouse over the page. (Tested on IE8, IE11, Firefox 30, Chrome 38.)
If you really need a timer-based solution, you combine this with some state variables:
(function() {
var mousePos;
document.onmousemove = handleMouseMove;
setInterval(getMousePosition, 100); // setInterval repeats every X ms
function handleMouseMove(event) {
var dot, eventDoc, doc, body, pageX, pageY;
event = event || window.event; // IE-ism
// If pageX/Y aren't available and clientX/Y are,
// calculate pageX/Y - logic taken from jQuery.
// (This is to support old IE)
if (event.pageX == null && event.clientX != null) {
eventDoc = (event.target && event.target.ownerDocument) || document;
doc = eventDoc.documentElement;
body = eventDoc.body;
event.pageX = event.clientX +
(doc && doc.scrollLeft || body && body.scrollLeft || 0) -
(doc && doc.clientLeft || body && body.clientLeft || 0);
event.pageY = event.clientY +
(doc && doc.scrollTop || body && body.scrollTop || 0) -
(doc && doc.clientTop || body && body.clientTop || 0 );
}
mousePos = {
x: event.pageX,
y: event.pageY
};
}
function getMousePosition() {
var pos = mousePos;
if (!pos) {
// We haven't seen any movement yet
}
else {
// Use pos.x and pos.y
}
}
})();
As far as I'm aware, you can't get the mouse position without having seen an event, something which this answer to another Stack Overflow question seems to confirm.
Side note: If you're going to do something every 100ms (10 times/second), try to keep the actual processing you do in that function very, very limited. That's a lot of work for the browser, particularly older Microsoft ones. Yes, on modern computers it doesn't seem like much, but there is a lot going on in browsers... So for example, you might keep track of the last position you processed and bail from the handler immediately if the position hasn't changed.
Here's a solution, based on jQuery and a mouse event listener (which is far better than a regular polling) on the body:
$("body").mousemove(function(e) {
document.Form1.posx.value = e.pageX;
document.Form1.posy.value = e.pageY;
})