BeniS made tests, loop is faster.

modules/corelib/ui/uitable.lua

@@ -132,7 +132,7 @@ function UITable:addRow(data, height)
   local row = g_ui.createWidget(self.rowBaseStyle, self.dataSpace)
   if height then row:setHeight(height) end
   local rowId = #self.rows
-  if rowId < 1 then rowId = 1 end
+  while rowId < 1 do rowId = rowId + 1 end
   rowId = 'row'..rowId
   row:setId(rowId)
 
@@ -210,4 +210,4 @@ function UITable:setHeaderColumnStyle(style)
   if table.hasKey(HEADER_ID) then
     self.columns[HEADER_ID]:setStyle(style)
   end
-end
+end