Use a little jQuery:
var oModel = this.getView().getModel(),
oContent = this.getView().byId("myPage").$().find("section");
jQuery(function($) {
oContent.bind('scroll', function() {
if($(this).scrollTop() + $(this).innerHeight()>=$(this)[0].scrollHeight) {
oModel.setProperty("/isFooterVisible", true);
}
});
});
and use data binding to toggle the state of your footer
See this example