Is it possible to change document.activeElement in JavaScript?
Is it possible to programmatically change the value of the document.activeElement property in JavaScript?
In IE, use the setActive() method of the element that you want to be the active element. In other browsers that support activeElement, you can use the focus() method of the element, so long as the element is capable of receiving the focus (form elements, editable elements, elements with tabindex set).
If you want to set the activeElement back to the default (the <body> element in most browsers), just call the active element's blur() method:
document.activeElement.blur();
You can just .focus() the element you want and it'll be the new document.activeElement.