In my experience, though, as long as you're using this hook on smaller components that don't have a big DOM impact, you should be just fine. pageX and event.pageY in combination with the jQuery offset() method to get the position of mouse pointer relative to an element. Use this hook in the small “leaf node” components near the bottom of the tree.įor maximum performance, you can use a library like React Spring or Framer Motion, which will allow you to update values without triggering React renders. It shouldn't be used in a top-level component like App or Homepage, since that will cause a huge chunk of your React tree to re-render very often. That said, you do still need to be a bit careful where you use this hook. The element will be clicked in this position to receive input focus. No matter how hard I tried, I couldn't come up with a contrived scenario where the throttle actually improved performance (while still updating often enough for smooth animations). The offsetLeft and offsetTop are subtracted from the current mouse position relative to the page to work out the mouse position relative to the. Specifies the mouse pointer coordinates relative to the target elements top-left corner. In testing, though, it seemed to make performance worse. Originally, this hook included “throttle” functionality, which would limit the updates to a user-specified interval. This can be dozens and dozens of times a second. What we want to do is figure out the exact click position when youĬlick anywhere inside the yellow container:įirst, we have the event listener setup to listen for aĬlick event: yellowContainer.This component will re-render whenever the user moves the mouse. The dimension of the canvas is found using the getBoundingClientRect () function. A function is created which takes in the canvas element and event as parameters. In that thread, let's start by looking at a seeminglyįine approach that seems like it should give us the exact position of The coordinates of the mouse whenever a click takes place can be found by detecting the click event with an event listener and finding the event’s x and y position. Pointing thing! A Worthy (But Incomplete) AttemptĪ great way to learn is by understanding why something doesn't work The system variable mouseX always contains the current horizontal position of the mouse, relative to (0, 0) of the canvas. The mouse (pointers) location is available relative to several coordinate systems: x,y - relative to the origin of the MouseEvents node, sceneX,sceneY. Here works on a touch device where a stylus or your finger is the "mouse" and "click" will appear often, just know that everything I show In this tutorial, I will explain the magic behind figuring out theĮxact pixel coordinates of where a click occurred. Something you may find yourself needing to do is figuringĪn example where knowing the exact click position isĬlick anywhere inside the gray box to see the red circle move to the After obtaining the required object, we can invoke the object.click (). This will gives us the object of the element, the image cursor is on. Mouse (or another pointing device like a stylus or finger). To do this, we use document.elementFromPoint (x+px, y+py) in which we pass the position of the image cursor. Fixed: The item is absolutely positioned in a fixed position on the screen even as the. The mouse coordinates relative to the parent element of the object that. The element is positioned in relation to its nearest non-static ancestor. The output of this function will return a two-element array where the first element is the x or column position. Getting the mouse position is another tricky feat when you involve both Explorer. It also needs to take into account any scrolling and the position of the image inside the. For all sorts of interactive doo-dads you will beĬreating, chances are you will be making heavy use of the Youll see that this works independent of a GUI. event method to find the coordinates of the mouse when it is clicked.
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