// params = text, image, action, text, image, action, ...
//   or TextImageAction...
//   or a list of above stuff
static DynamicHStack showNiceButtons(O... params) {
  DynamicHStack stack = makeNiceButtons(params);
  showCenterPackedFrame(withMargin(20, jHigherScrollPane(jfullcenter(stack))));
  ret stack;
}