set variable in AMSlide Menu according to the row selected. iOS

Question

I am developing a content display app in which there is a table view and a detail view. there is a Left menu to browse through different categories in which the content is changing but the display method is same.

I am using AMSlide Menu library for the left menu panel. Earlier i used Different screens in story board for different categories which had their defined json links from which data is fetched.

But only the json link is changing not the content format so i decided to remove the screens from storyboards and delete the classes. now the app is very light weight but i am not able to set the value of the json link according to the row selected in the left menu.

Following is the code in AmSlide menu segues are performed but when i try to set variable , it giving error

-(NSString *)segueIdentifierForIndexPathInLeftMenu:(NSIndexPath *)indexPath

{

    NSString *idetifier = nill;
    switch (indexPath.row) {
      case 0:
         break;
     case 1:
         idetifier = @"secondSegue";
         break;
     case 2:
         idetifier = @"thirdSegue";
         break;
        }
    return idetifier;
}