private Integer addNewRefLabel(String currLabel) {
    // Register a new relationship within this tab
    mRefLabelToRow.put(currLabel, mNextRefLabelIndex);

    // Paint the new label at the bottom of the reference label table
    mRefLabelTable.appendText(currLabel);

    // Add empty spaces to all other ref data tables
    for (DataTable t : mRefDataTables) t.addEmptyRow();

    return mNextRefLabelIndex++;
  }
  private int addNewDataLabel(String label) {
    // Register a new relationship within this tab
    mDataLabelToRow.put(label, mNextLabelIndex);

    // Paint the new label at the bottom of the label table
    mLabelTable.appendText(label);

    // Add empty spaces to all other data tables
    for (DataTable t : mDataTables) t.addEmptyRow();

    return mNextLabelIndex++;
  }