Add JqueryUI dialog button based on a condition

Question

I have a Jquery dialog where I want to display button based on a condition.

I tried using this solution to extend the button set but it's not displaying the dynamic button: Add a button to a dialog box dynamically

https://jsfiddle.net/q3u0xebz/

function showActionDialog(title, content, actionMessage, actionCallback) {
  var actionDialog = $("<div id='action-dialog'></div>").html(content).dialog({
    dialogClass: 'no-close',
    title: title,
    resizable: false,
    height: 'auto',
    width: 'auto',
    modal: true,
    buttons: [{
      text: 'Okay',
      click: function() {
        $(this).dialog('close');
        $("action-dialog").remove();
      }
    }]

  });

  if (actionCallback != '') {
    var buttons = actionDialog.dialog("option", "buttons"); // getter

    $.extend(buttons, {
      text: actionMessage,
      click: function() {
        eval(actionCallback).call();

        $(this).dialog('close');
        $("action-dialog").remove();
      }
    });

    actionDialog.dialog("option", "buttons", buttons); // setter
  }
}