What is the benefit of calling beginUpdates/endUpdates for a UITableView as opposed to not doing so?

Question

I have an array of arrays that I\'m using for the data source of a table view. In one instance of time, I may have to do some complicated modifications to this data structur

Answer 1

Every time you add/remove a table item the tableView:numberOfRowsInSection: method is called - unless you surround these calls with begin/endUpdate. If your array and table view items are out of sync, without the begin/end calls an exception will be thrown.