// Add click handlers for buttons to show and hide modal popup on pageLoad
function pageLoad() {
    $addHandler($get("showModalPopupClientButton"), 'click', showModalPopupViaClient);
    $addHandler($get("hideModalPopupViaClientButton"), 'click', hideModalPopupViaClient);        
}

function showModalPopupViaClient(ev) {
    ev.preventDefault();
    var modalPopupBehavior = $find('programmaticModalPopupBehavior');
    modalPopupBehavior.show();
}

function hideModalPopupViaClient(ev) {
    ev.preventDefault();        
    var modalPopupBehavior = $find('programmaticModalPopupBehavior');
    modalPopupBehavior.hide();
}