传递数据，在另一个ViewController中仍为零

Question

我在A中有两个ViewController我尝试在B V.C中传递一个User对象，但它仍然是nil：

在A：

User * user = (self.users)[indexPath.row];


UIStoryboard *sb = [UIStoryboard storyboardWithName:@"Main" bundle:nil];

CVUserDetailsViewController *userVC = (CVUserDetailsViewController *)[sb instantiateViewControllerWithIdentifier:@"CVUserViewController"];

userVC.selectedUser = [[User alloc] init];
userVC.selectedUser = user;



-> breakpoint [self.navigationController pushViewController:userVC animated:YES];

在断点处，用户对象＆＃34; selectedUser＆＃34;不是零并且包含数据。

但是在加载B时这里：

//Instanciate a new header profile from CVUserHeaderView
    _header = [[CVUserHeaderView alloc] initWithFrame:CGRectMake(0, 63, self.view.frame.size.width, 160)];
    _header.backgroundColor = [UIColor whiteColor];

//Add the attributes
_header.trigram = _selectedUser.trigram;
_header.title_job = _selectedUser.title_job;
_header.main_skills = @"IOS, Android";
  --->breakpoint 2  _header.mission_state = _selectedUser.mission_state;

我的_selectedUser对象是nil，我做错了什么？