ios - Delete NSManagedObject and later refresh tableView doesn't work correctly -

i have 2 nsmanagedobject (person , car) , relationship "not inverse" between them. relationship not inverse.

i have 2 viewcontrollers, first 1 has tableview shows each instance of person object , second has table view shows every car of person. first view controller shows name of person , number of cars of person.

all works fine issue appear when try delete car of person. think remove object correctly:

[_person removecarssobject:car1]; 

but issue appear when being in second view, remove car, , go first view: number of cars doesn't refresh , app crashes.

when add car , go second view works , 'number of cars' increases.

when run app again, car deleted. why think way delete object correct.

i've realized app works number of cars going take value 0, otherwise app crashes.

i hope can me, thank you!

update:

i’ve changed code, , reload data of table view in

- (void)viewwillappear:(bool)animated{ 

this way can see proper data in table view, but, 1 second approx, later app crashes log: “thread 1: exc_bad_access(code=exc_i386_gpflt)"

all relationships in "model data" have delete rule property : nullify. maybe causing crash.

finally have issue solved. enabling zombie objects got more information crash. app crashing following message:

[viewcontroller tableview:caneditrowatindexpath:]: message sent deallocated instance 0xaae64d0

i had method this:

- (bool)tableview:(uitableview *)tableview caneditrowatindexpath:(nsindexpath *)indexpath {       return yes;    } 

searching, found question in stackoverflow says same: tableview:caneditrowatindexpath: crash when popping viewcontroller

the issue solved adding following code:

- (void)viewwilldisappear:(bool)animated {    [super viewwilldisappear:animated];    [table setediting:no]; }