/*
    2011 Jul 25:    huudungle
    Hiển thị Loading Overlay 
*/
function showOverlay(layerID) {
    var x = $(layerID).overlay({
        color: '#ccc',
        top: 50,
        mask: {
            color: '#000',
            loadSpeed: 200,
            opacity: 0.5,
            effect: 'apple'
        },
        closeOnClick: true,
        load: false
    });
    $(layerID).data('overlay').load();
}
function closeOverlay(layerID) {
    $(layerID).data('overlay').close();
}