How to determine if a browser window is activated

Question

Currently using im code

var focus;
function focuswindow() { focus = true; }
function hidewindow() { focus = false; }
window.onfocus = focuswindow();
window.onblur = hidewindow();

The idea is that it can be used as

if( focus ) { //do something
}

However its not working. Also, it should only work in Chrome (so no IE obsolete things), since it is intended to be a Chrome extension.

Answer 1

The reason it doesn't work is because you call the functions immediately and assign the return value undefinedto onfocusand onblur.

Instead, onfocusthey onblurmust reference functions by name.

Try the following:

window.onfocus = focuswindow;
window.onblur = hidewindow;

, (). onfocus onblur .