iphone - How to use UISegmentControl to change detailViewController of CoreData -

i have implemented uisegmentcontrol rightbarbutton of detailviewcontroller. view controller displays of information passed through uitableview. uitableview's cells populated coredata attribute values.

what want enable user go , down in list via detailviewcontroller. instead of having make user have go rootviewcontroller, they'll gain ability scroll through via uisegmentcontrol.

i have in detailviewcontroller.m

 - (void)viewwillappear:(bool)animated { [super viewwillappear:animated];  // setting uisegmentedcontrol  // segmented control - custom right bar button view uisegmentedcontrol *segmentedcontrol = [[uisegmentedcontrol alloc] initwithitems:                                         [nsarray arraywithobjects:                                          [uiimage imagenamed:@"arrowdown.png"],                                          [uiimage imagenamed:@"arrowup.png"],                                          nil]];  [segmentedcontrol addtarget:self action:@selector(segmentaction:) forcontrolevents:uicontroleventvaluechanged];  segmentedcontrol.frame = cgrectmake(0, 0, 75, 30); segmentedcontrol.segmentedcontrolstyle = uisegmentedcontrolstylebar; segmentedcontrol.momentary = yes;  uibarbuttonitem *segmentbaritem = [[uibarbuttonitem alloc] initwithcustomview:segmentedcontrol]; [segmentedcontrol release];  self.navigationitem.rightbarbuttonitem = segmentbaritem; [segmentbaritem release];   } 

this attached following method, detecting tapped control.

 - (void)segmentaction:(id)sender  { uisegmentedcontrol* segctl = sender; // segmented control clicked, handle here   if([segctl selectedsegmentindex]==0){     nslog(@"you clicked down arrow - segment clicked %d", [segctl selectedsegmentindex]); }else {      nslog(@"you clicked arrow - segment clicked %d", [segctl selectedsegmentindex]);  }    } 

i curious whether or not knows how detect whether or not there anymore go to. say, if note loaded in first position, down arrow disabled, , if note loaded in last position, arrow disabled. possible?

any appreciated.

i'd suggest create formal protocol mydatasource provides methods accessing data. minimum, there must method number of data objects , object specified index.

in detailviewcontroller should have reference object conforms mydatasource. i'd recommend use instance of rootviewcontroller data source detailviewcontroller.

you should keep track of index of object displayed in detailviewcontroller , update ui appropriately.