Web Page Theatre Mode Overlay Tutorial CSS Javascript Light Switch Toggle Darkness
Learn to program web page theatre mode darkness using a CSS and JavaScript overlay. This one uses a light switch as the user interface to allow a viewer to toggle the page in and out of theatre mode. Our elements and their CSS are structured a little bit differently to focus on an existing special content box on the page as opposed to bringing a new DIV into the center of the page. Stemming off of our earlier overlay tutorial: http://www.developphp.com/view.php?tid=1254
<!-- Example by Adam Khoury @ www.developphp.com -->
<!DOCTYPE html>
<html>
<head>
<style type="text/css">
div#overlay {
display:none;
z-index: 2;
background:url(style/opaqueDark.png);
position:fixed;
width:100%;
height:100%;
top:0px;
left:0px;
text-align:center;
}
img#lightSwitch {
position:relative;
z-index: 3;
background:url(images/light_switch_down.jpg) no-repeat;
cursor:pointer;
}
div#special {
position:relative;
z-index: 4;
}
</style>
<script type="text/javascript">
function toggleTheatreMode(){
var overlay = document.getElementById('overlay');
var lightSwitch = document.getElementById('lightSwitch');
if(overlay.style.display == "block"){
overlay.style.display = "none";
lightSwitch.src = "images/light_switch_up.jpg";
lightSwitch.title = "Enter Theatre Mode";
} else {
overlay.style.display = "block";
lightSwitch.src = "images/light_switch_down.jpg";
lightSwitch.title = "Exit Theatre Mode";
}
}
</script>
</head>
<body>
<!-- Start Overlay -->
<div id="overlay"></div>
<!-- End Overlay -->
<h1>Web page theatre mode example</h1>
<img id="lightSwitch" onmousedown="toggleTheatreMode()" src="images/light_switch_up.jpg" width="19" height="46" alt="switch" title="Enter Theatre Mode"> <h3 style="display:inline;">I can put a title here if I want</h3>
<div id="special">
<iframe width="560" height="315" src="http://www.youtube.com/embed/69-R9GHcGWU" frameborder="0" allowfullscreen></iframe>
</div>
<h2>My web page has a lot off stuff on it</h2>
</body>
</html>
Web Page Theatre Mode Overlay Tutorial CSS Javascript Light Switch Toggle Darkness