iphone - compilation error for navigation controller -

i new in objective c. don't know more things this. practicing on navigation controller. problem whatever methods putting in action:@selector in shows sigabrt error. clarify me types of methods can put in action:@selector section. though know it's silly question think these clear concept on navigationviewcontroller.

thank you.

- (void)viewdidload {     uisearchbar *search=[[uisearchbar alloc] init];      self.navigationitem.rightbarbuttonitem=[[uibarbuttonitem alloc]initwithbarbuttonsystemitem:uibarbuttonsystemitemsearch target:self action:@selector(searchbarshouldbeginediting:)];     [super viewdidload]; }   - (bool)searchbarshouldbeginediting:(uisearchbar *)searchbar{      uisearchbar *search=[[uisearchbar alloc] init];     [search resignfirstresponder];     return yes;  } 

try moving '[super viewdidload]' beginning of viewdidload method, not end. need make sure controls exist before add right bar button item.