添加手势识别器时,SWRevealViewController为零

Question

我正在开发一个将使用SWRevealViewController类的应用程序.该应用程序到目前为止工作,我可以点击左栏按钮项目带出后视图控制器,但当我在前视图控制器中添加手势识别器时,SWRevealViewController是零.我不知道为什么这样,所以任何帮助将不胜感激.

//not nil here. 
SWRevealViewController *revealController = [self revealViewController];
//somehow it becomes nil on the very next line and from then on I can't hold the reference to it
[self.navigationController.navigationBar addGestureRecognizer:[revealController panGestureRecognizer]];

UIBarButtonItem *revealButtonItem = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"reveal-icon.png"]
                                                                     style:UIBarButtonItemStyleBordered target:revealController action:@selector(revealToggle:)];

Answer 1

您使用故事板吗？

如果是这样，在您的 中prepareForSegue:，您是否确保您的 segue 属于该类SWRevealViewControllerSegue，如下所示？

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if ([segue isKindOfClass: [SWRevealViewControllerSegue class]]) {

        SWRevealViewControllerSegue* rvcs = (SWRevealViewControllerSegue*) segue;

        SWRevealViewController* rvc = self.revealViewController;

        rvcs.performBlock = ^(SWRevealViewControllerSegue* rvc_segue, UIViewController* svc, UIViewController* dvc) {

        UINavigationController* nc = [[UINavigationController alloc] initWithRootViewController:dvc];
        [rvc setFrontViewController:nc animated:YES];
        };
    } 
}

我刚刚为我的项目解决了这个问题，当我使用传统的 [segue destinationViewController] 方法时， self.revealViewController 为零。