how to add function on right click
if (document.addEventListener) {
document.addEventListener('contextmenu', function(e) {
alert("You've tried to open context menu"); //here you draw your own menu
e.preventDefault();
}, false);
} else {
document.attachEvent('oncontextmenu', function() {
alert("You've tried to open context menu");
window.event.returnValue = false;
});
}