如果您没有数据，或者您没有其他单元格的数据，那么 cellForRowAtIndex：。该值设置在 numberOfRowsInSection：。

If you don't have data, or you don't have the data for additional cells, then cellForRowAtIndex: will not be called as long as you don't tell the UTableView that you have rowCounts or new rowCounts. That value is being set in numberOfRowsInSection:.

换句话说，不报告 numberOfRowsInSection：，直到你实际拥有该数据为止，然后 cellForRowAtIndexPath：将不会过早被调用。

In other words, don't report any new cells in numberOfRowsInSection:, until you actually have that data in hand, and then cellForRowAtIndexPath: won't be called prematurely.

当你获得额外的行数据时，然后调用 reloadData 来让UITableView询问行数和然后调用 cellForRowAtIndex：。

When you do get the additional row data, then call reloadData to get the UITableView to ask for the number of rows and then call cellForRowAtIndex:.