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Asked: 2026-05-28T17:06:48+00:00

I was trying to understand why numberOfSectionsInTableView is being called multiple times each time

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I was trying to understand why numberOfSectionsInTableView is being called multiple times each time I update my data source. From the stack trace in gdb, I see the following

#0  -[JobPickerTVC numberOfSectionsInTableView:] (self=0x4d61fe0, _cmd=0x6207f5, tableView=0x6034800) at JobPickerTVC.m:153
#1  0x003d66ff in -[UITableViewRowData(UITableViewRowDataPrivate) _updateNumSections] ()
#2  0x003d63b0 in -[UITableViewRowData invalidateAllSections] ()
#3  0x00299010 in -[UITableView(_UITableViewPrivate) _endCellAnimationsWithContext:] ()
#4  0x002891e8 in -[UITableView endUpdates] ()
#5  0x000050c8 in -[JobPickerTVC controllerDidChangeContent:] (self=0x4d61fe0, _cmd=0x17109d, controller=0x4da5e40) at JobPickerTVC.m:442

followed by

#0  -[JobPickerTVC numberOfSectionsInTableView:] (self=0x4d61fe0, _cmd=0x6207f5, tableView=0x6034800) at JobPickerTVC.m:153
#1  0x003d66ff in -[UITableViewRowData(UITableViewRowDataPrivate) _updateNumSections] ()
#2  0x003d6417 in -[UITableViewRowData ensureAllSectionsAreValid] ()
#3  0x0029902e in -[UITableView(_UITableViewPrivate) _endCellAnimationsWithContext:] ()
#4  0x002891e8 in -[UITableView endUpdates] ()
#5  0x000050c8 in -[JobPickerTVC controllerDidChangeContent:] (self=0x4d61fe0, _cmd=0x17109d, controller=0x4da5e40) at JobPickerTVC.m:442

From what I can tell, the code executes [UITableViewRowData invalidateAllSections] (line #2 of the first trace) and then [UITableViewRowData ensureAllSectionsAreValid] (line #2 of the second trace). Both of these end by calling [JobPickerTVC numberOfSectionsInTableView:]. So [JobPickerTVC numberOfSectionsInTableView:] is getting called twice. I would like to know why this is happening and what these operations are doing.

There’s one more call to numberOfSectionsInTableView for another reason, but I would like to understand these first.

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1 Answer

  1. Editorial Team

    Your table numberOfSectionsInTableView is getting called multiple times because you are reloading your table data.whenever you reload table,this method will check for all delegates of tableview.

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