Full Screen in JavaScript (cross-browser) - another approach, with two different buttons

fullscreen2.js

// quando clicco su enterfullscreen:
    // vai in fullscreen
    // mostra pulsante exitfullscreen
    // nascondi header e footer    

// quando clicco su exitfullscreen:
    // esci da fullscreen
    // mostra pulsante enterfullscreen
    // mostra header e footer

function toggleFullScreen() {
    if (!document.fullscreenElement &&    // alternative standard method
        !document.mozFullScreenElement && !document.webkitFullscreenElement) {  // current working methods
        if (document.documentElement.requestFullscreen) {
            document.documentElement.requestFullscreen();
        } else if (document.documentElement.mozRequestFullScreen) {
            document.documentElement.mozRequestFullScreen();
        } else if (document.documentElement.webkitRequestFullscreen) {
            document.documentElement.webkitRequestFullscreen(Element.ALLOW_KEYBOARD_INPUT);
        }
    } else {
        if (document.cancelFullScreen) {
            document.cancelFullScreen();
        } else if (document.mozCancelFullScreen) {
            document.mozCancelFullScreen();
        } else if (document.webkitCancelFullScreen) {
            document.webkitCancelFullScreen();
        }
    }
}

function toggleFullScreenButtons() {
    $(_objects.enterfullscreen).toggle();
    $(_objects.exitfullscreen).toggle();
}

function toggleHeaderFooter() {
    $('#header').slideToggle('slow');
    $('#footer').slideToggle('slow');
}

function doToggleFullScreen() {
    toggleFullScreen();
    toggleFullScreenButtons();
    toggleHeaderFooter();
}

$('.enterfullscreen').on('click', function() {
    doToggleFullScreen();
});

$('.exitfullscreen').on('click', function() {
    doToggleFullScreen();
});

style.css

.enterfullscreen,
.exitfullscreen {
    background-repeat: no-repeat;
}

.enterfullscreen {
    background-image: url(/content/images/openfullscreen.png);
    width:12px;
    height: 12px;

    position: absolute;
    top:22px;
    right:0;
}
.exitfullscreen {
    background-image: url(/content/images/closefullscreen.png);
    width: 27px;
    height: 29px;

    position: fixed;
    top: 10px;
    right: 10px;
    z-index: 10;

    display:none;
}