Question

我有一个PFQueryTableViewController，设置为在选择行时在UINavigationViewController内实例化并显示一个新的视图控制器。

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    if ([self objectAtIndexPath:indexPath]) { // Check our object exists
        MyNewViewController *card = [[MyNewViewController alloc] init];

        UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:card];
        [nav.navigationBar configureFlatNavigationBarWithColor:[UIColor pomegranateColor]];
        [self presentViewController:nav animated:YES completion:^{}];
    }
    else { // Otherwise, do what we would have done.
        [super tableView:tableView didSelectRowAtIndexPath:indexPath];
    }
}

当我选择一行时，表视图会在显示新视图控制器之前一直滚动（不是动画）到顶部。这是第一个问题，因为它使用户难以跟踪它们的位置。

第二个问题是，当我退出新的视图控制器，返回到表视图控制器时，我无法从第一个单元格向下滚动。它反弹，我可以看到一些第二个细胞，但它不会降低。重新加载表会导致滚动再次起作用。

如何防止它滚动到顶部，为什么在滚动到顶部后限制滚动？

Answer 1

尝试这样的事情：

@implementation PFQueryTableViewController
{
    UIViewController* _rootViewController;
    UINavigationController* _nav
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    if ([self objectAtIndexPath:indexPath]) { // Check our object exists
        MyNewViewController *card = [[MyNewViewController alloc] init];

        _nav = [[UINavigationController alloc] initWithRootViewController: card];
        [nav.navigationBar configureFlatNavigationBarWithColor: [UIColor pomegranateColor]];
        AppDelegate* appDelegate = (AppDelegate*)[[UIApplication sharedApplication] delegate];
        _rootViewController = appDelegate.window.rootViewController;

        [UIView transitionFromView: _rootViewController
                            toView: _nav.view
                          duration: 0.5
                           options: UIViewAnimationOptionTransitionFlipFromRight |
         UIViewAnimationOptionAllowUserInteraction    |
         UIViewAnimationOptionBeginFromCurrentState
                        completion: ^(BOOL finished)
         {
             appDelegate.window.rootViewController = nav;
             [appDelegate.window makeKeyAndVisible];
         }];
    }
    else { // Otherwise, do what we would have done.
        [super tableView:tableView didSelectRowAtIndexPath:indexPath];
    }
}

然后从navcontroller中调用下一个返回表格的方法：

- (void) returnToTheQueryTableViewController
{
    [UIView transitionFromView: _nav.view
                        toView: _rootViewController.view
                      duration: 0.5
                       options: UIViewAnimationOptionTransitionFlipFromRight |
     UIViewAnimationOptionAllowUserInteraction    |
     UIViewAnimationOptionBeginFromCurrentState
                    completion: ^(BOOL finished)
     {
         AppDelegate* appDelegate = (AppDelegate*)[[UIApplication sharedApplication] delegate];
         appDelegate.window.rootViewController = _rootViewController;
         [appDelegate.window makeKeyAndVisible];
     }];
}

希望这会对你有所帮助。

呈现另一个视图控制器将UITableView滚动到顶部

1 个答案: