abstract sclass DynBigNumber extends DynModule {
  S description;
  O value;
  int fontSize = 40;
  S toolTip;
  
  transient JLabel label;
  transient SimpleLiveValue<S> lvText = new(S);
  transient SimpleLiveValue<S> lvDesc = new(S);
  
  // PUBLIC API
  
  // any Number, or anything persistable with toString
  bool setValue(O value) {
    bool changed = setField(+value);
    makeTexts();
    ret changed;
  }
  
  void setDescription(S desc) {
    setField('description, desc);
    makeTexts();
  }
  
  O getValue() { ret value; }
  S getDescription() { ret description; }
  void setToolTip(S toolTip) { setField(+toolTip); }
  
  void doPersist() {
    _persistenceInfo = mapMinusOrNull(_persistenceInfo, 'value);
  }
  
  // END PUBLIC API
  
  void makeTexts() {
    lvText.set(value == null ? "-" : str(value));
    lvDesc.set(description);
  }
  
  start {
    _persistenceInfo = mapPlus(_persistenceInfo, value := false);
    makeTexts();
  }

  visualize {
    ret bindToolTipToLiveValue(dm_fieldLiveValue('toolTip),
      jLiveValueSection(lvDesc,
        centerLabel(makeBold(setFontSize(fontSize, label = jLiveValueLabel(lvText))))));
  }
}