如何在表视图中选择后将数据传递到详细视图？

Question

我有一个UITableViewController,其中包含从名为userList的NSMutableArray填充的数据.选择特定用户后,它将转到详细视图,并更新NavBar中的标题,但它不会传递数据以更新UIView中的UILabel.

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {

[tableView deselectRowAtIndexPath:indexPath animated:NO];

//Attempt at a singleton to pass the data
DetailView *details = [[DetailView alloc] init];
details.userNameLbl = [userList objectAtIndex:indexPath.row];


DetailView *detailVC = [[DetailView alloc] initWithNibName:nil bundle:nil];

//This line doesn't pass the data
detailVC.userNameLbl.text = [userList objectAtIndex:indexPath.row];

//This line does update the title in the NavBar
detailVC.navigationItem.title = [userList objectAtIndex:indexPath.row];

[self.navigationController pushViewController:detailVC animated:YES];

[details release];
[detailVC release];

}

我应该尝试将数据从表视图推送到详细视图,还是让详细视图尝试从表视图中提取数据？

DetailView.h实际上是在IB中连接的以下行.

IBOutlet UILabel *userNameLbl

Answer 1

在userNamelbl从nib文件加载视图之前,不会实例化.这不会在初始化时立即发生,但会在viewDidLoad调用时发生.

因此,您应该在DetailView中声明一个属性来存储标题,然后userNamelbl.text在该viewDidLoad方法中指定该值.

例如,在你的表viewController中:

DetailView *detailVC = [[DetailView alloc] initWithNibName:nil bundle:nil];
detailVC.userName = [userList objectAtIndex: indexPath.row];

并在您的详细视图中控制:

- (void) viewDidLoad
{
   [super viewDidLoad];
   self.userNameLbl.text = self.userName;
}

viewController的navigationItem属性是在viewController初始化时创建的,因此您可以navigationItem.title立即分配.

SWIFT代码

let detailVC = DetailView(nibName: nil, bundle: nil)
detailVC.userName = userList.objectAtIndex(indexPath.row) as? NSString

和

class DetailView: UIViewController {

    @IBOutlet var userNameLbl: UILabel
    var userName:NSString?

    override func viewDidLoad() {
        super.viewDidLoad()
        self.userNameLbl.text = self.userName
    }    
}