Test if window has focus

by Jennifer Perrin

HTML

<button id="clear">clear log</button>
<div id="event"></div>

JavaScript

$(function(){
    
    $hasFocus = false;
    
    $('#clear').bind('click', function() { $('#event').empty(); });
    
    $(window)
        .bind('focus', function(ev){
            $hasFocus = true;
            $('#event').append('<div>'+(new Date()).getTime()+' focus</div>');
        })
        .bind('blur', function(ev){
            $hasFocus = false;
            $('#event').append('<div>'+(new Date()).getTime()+' blur</div>');
        })
        .trigger('focus');
    
    setInterval(function() {
        $('#event').append('<div>'+(new Date()).getTime()+' has focus '+($hasFocus ? 'yes' : 'no')+'</div>');
    }, 2000);
});