* @param callback - the callback used when a button of the dialog is taped
*/
public ConfirmDialog(DialogPanelAppearance appearance, String title, String text, ConfirmCallback callback, String okButtonText, String cancelButtonText) {
this.callback = callback;
popinDialog = new PopinDialogOverlay(appearance);
dialogPanel1 = new DialogPanel(appearance);
dialogPanel1.showCancelButton(true);
dialogPanel1.showOkButton(true);
textLabel = new Label();
dialogPanel1.getContent().add(textLabel);