ios - Item isn't adding in the to-do list in xcode -

i followed tutorial apple , made to-do list app in objective c in xcode 6. reason, when type items name in textfield while app runs in simulator, , press 'save', isn't adding in list of to-do items.

@interface todolisttableviewcontroller ()  @property nsmutablearray *todoitems;  @end  @implementation todolisttableviewcontroller  - (ibaction)unwindtolist:(uistoryboardsegue *)segue {     addtodoitemviewcontroller *source = [segue sourceviewcontroller];     todoitem *item = source.todoitem;     if (item != nil) {         [self.todoitems addobject:item];         [self.tableview reloaddata];     } }    - (void)viewdidload {     [super viewdidload];     self.todoitems = [[nsmutablearray alloc]init];     [self loadinitialdata]; }  - (void)didreceivememorywarning {     [super didreceivememorywarning];  }  - (void)loadinitialdata {     todoitem *item1 = [[todoitem alloc] init];     item1.itemname = @"buy milk";     [self.todoitems addobject:item1];     todoitem *item2 = [[todoitem alloc] init];     item2.itemname = @"buy eggs";     [self.todoitems addobject:item2];     todoitem *item3 = [[todoitem alloc] init];     item3.itemname = @"read book";     [self.todoitems addobject:item3];  }  #pragma mark - table view data source  - (nsinteger)numberofsectionsintableview:(uitableview *)tableview {     // return number of sections.     return 1; }  - (nsinteger)tableview:(uitableview *)tableview numberofrowsinsection:     (nsinteger)section {     // return number of rows in section.     return [self.todoitems count]; }   - (uitableviewcell *)tableview:(uitableview *)tableview cellforrowatindexpath:    (nsindexpath *)indexpath {     uitableviewcell *cell = [tableview dequeuereusablecellwithidentifier:@" listprototypecell" forindexpath:indexpath];      todoitem *todoitem = [self.todoitems objectatindex:indexpath.row];     cell.textlabel.text = todoitem.itemname;     return cell; } 

here code addtodoitem file.

#import "addtodoitemviewcontroller.h"  @interface addtodoitemviewcontroller () @property (weak, nonatomic) iboutlet uitextfield *textfield; @property (weak, nonatomic) iboutlet uinavigationitem *savebutton;  @end  @implementation addtodoitemviewcontroller  - (void)viewdidload {     [super viewdidload];     // additional setup after loading view. }   - (void)didreceivememorywarning {     [super didreceivememorywarning];     // dispose of resources can recreated. }   #pragma mark - navigation  - (void)prepareforsegue:(uistoryboardsegue *)segue sender:(id)sender {     if (sender != self.savebutton) return;     if (self.textfield.text.length > 0) {         self.todoitem = [[todoitem alloc] init];         self.todoitem.itemname = self.textfield.text;         self.todoitem.completed = no;     } }  @end 

here calling unwindtolist action.

@interface todolisttableviewcontroller : uitableviewcontroller  - (ibaction)unwindtolist:(uistoryboardsegue *)segue;  @end 

has else same problem or can me? i've compared codes , codes in tutorial can't find differences...

thanks in advance!