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?
This question is related to
javascript
input
mouse
user-input
input-devices
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.
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();
});
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
}
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();"
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:
MouseEvent.buttonsMouseEvent.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 leftMouseButtonOnlyDown = false;
function setLeftButtonState(e) {
leftMouseButtonOnlyDown = e.buttons === undefined
? e.which === 1
: e.buttons === 1;
}
document.body.onmousedown = setLeftButtonState;
document.body.onmousemove = setLeftButtonState;
document.body.onmouseup = setLeftButtonState;
If more complicated scenarios are required (different buttons/multiple buttons/control keys), check out the MouseEvent docs. When/if Safari lifts its game, this should get easier.
As said @Jack, when mouseup happens outside of browser window, we are not aware of it...
window.addEventListener('mouseup', mouseUpHandler, false);
window.addEventListener('mousedown', mouseDownHandler, false);
mouseup event in one of those cases: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.
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
}
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.
You need to handle the MouseDown and MouseUp and set some flag or something to track it "later down the road"... :(
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 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);
}
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.
You need to handle the MouseDown and MouseUp and set some flag or something to track it "later down the road"... :(
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
}
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();
});
Using the MouseEvent api, to check the pressed button, if any:
document.addEventListener('mousedown', (e) => console.log(e.buttons))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)
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.
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 the MouseEvent api, to check the pressed button, if any:
document.addEventListener('mousedown', (e) => console.log(e.buttons))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)
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);
}
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:
MouseEvent.buttonsMouseEvent.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 leftMouseButtonOnlyDown = false;
function setLeftButtonState(e) {
leftMouseButtonOnlyDown = e.buttons === undefined
? e.which === 1
: e.buttons === 1;
}
document.body.onmousedown = setLeftButtonState;
document.body.onmousemove = setLeftButtonState;
document.body.onmouseup = setLeftButtonState;
If more complicated scenarios are required (different buttons/multiple buttons/control keys), check out the MouseEvent docs. When/if Safari lifts its game, this should get easier.
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.
}
You need to handle the MouseDown and MouseUp and set some flag or something to track it "later down the road"... :(
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...
window.addEventListener('mouseup', mouseUpHandler, false);
window.addEventListener('mousedown', mouseDownHandler, false);
mouseup event in one of those cases: 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.
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.
}
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.
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 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);
}
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.
You need to handle the MouseDown and MouseUp and set some flag or something to track it "later down the road"... :(
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
}
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.
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.
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.
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);
}
Source: Stackoverflow.com