This occurs because the resize event triggers a render, during which React updates the display, including the current value of window.innerHeight.

There is only a hook to set the width, however window.innerHeight also updates when the window is resized. You might notice something odd about this code.

The code below shows the simplest method to do this. Calling useEffect without any dependencies accomplishes this feat. Modern React apps use hooks, so calling a method once is a little tricky. You can get the outer window size with window.outerWidth and window.outerHeight. To install a handler, it's necessary for the code to run once, certainly not in the render loop. Screen resolution detection with Javascript.

The React render lifecycle runs whenever the page content changes, usually in response to input. This is done by handling the resize event in JavaScript. however it might not have been fully rendered - and images might not be loaded yet.Sometimes it's necessary to execute logic in a React app when the browser is resized or when the mobile device is rotated. A global variable, window, representing the window in which the script is running, is exposed to JavaScript code. For example, let’s add an event to the object window to get its width and height and show it on the web page. This function adds an event that contains a function to an object. ^ But, if you use this instead of onload handler: The html document would have been read into the browser. To add a resize event to the window, we can use the addEventListener () function in JavaScript. and could also have some other js functions in it.Įdit #2: You could also place the script section, just before the end of the document. Imagine the chaos that could ensue if any random function could. Įdit: The external script name, doesn't need to be named the same as the function of course. Fortunately, you cannot move or resize a browser window your JavaScript code did not create.

Javascript window resize