ios - UIActivityViewController 在使用 sourceView 或 barButtonItem 的 iPad 上崩溃

Question

我遇到过大多数人在 iPad 上尝试呈现 UIActivityViewController 时遇到的情况；它崩溃了:

Terminating app due to uncaught exception 'NSGenericException', reason: 'UIPopoverPresentationController (<_UIAlertControllerActionSheetRegularPresentationController: 0x7fc4f2d87d00>) should have a non-nil sourceView or barButtonItem set before the presentation occurs.

这是我的代码:

- (void)shareLeaflet
{
    NSString *forwardedString = [[NSString alloc] initWithFormat:@"Check out this leaflet\n\n %@ \n\nself.theURLToShare];
    UIActivityViewController *activityViewController = nil;

    if (IDIOM == IPAD)
    {
        NSLog(@"iPad");
        activityViewController.popoverPresentationController.sourceView = self.view;
//        activityViewController.popoverPresentationController.sourceRect = self.frame;
        [self presentViewController:activityViewController
                           animated:YES
                         completion:nil];

    }
    else
    {
        NSLog(@"iPhone");
        activityViewController = [[UIActivityViewController alloc] initWithActivityItems:[NSArray arrayWithObjects:forwardedString, nil] applicationActivities:nil];
        [self presentViewController:activityViewController animated:YES completion:nil];


    }

在我的 viewDidLoad 中，我有:

UIBarButtonItem *composeButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAction target:self                                    action:@selector(shareLeaflet)];

    self.navigationItem.rightBarButtonItem = composeButton;
}

此 View 是一个 UIPageViewController，它展示了一些图像，当用户点击共享按钮时，我希望弹出 iOS 8 样式的共享表。这正是 iPhone 上发生的情况，但在 iPad 上，它继续崩溃。这让我想到了 Stack Overflow，但没有一个问题( crash on showing UIPopOverPresentationController 、 iOS Crash: Terminating app due to uncaught exception reason: UIPopoverPresentationController should have a non-nil sourceView 、 UIWebViewTerminating app due to UIPopoverPresentationController 、 ios8 iPad uiwebview crashes while displaying popover when user taps drop down list HTML select tag 等)对我有用。

我已经尝试了其中的所有解决方案，并且完全明白了它的要求。

这就是我要实现的目标:

对此有任何想法将不胜感激。

Answer 1

您没有在 iPad 上初始化 activityViewController，因此它将始终为 nil。

尝试:

- (void)shareLeaflet
{
    NSString *forwardedString = [[NSString alloc] initWithFormat:@"Check out this leaflet\n\n %@ \n\nself.theURLToShare];
    UIActivityViewController *activityViewController = [[UIActivityViewController alloc] initWithActivityItems:[NSArray arrayWithObjects:forwardedString, nil] applicationActivities:nil];

    if (IDIOM == IPAD)
    {
        NSLog(@"iPad");
        activityViewController.popoverPresentationController.sourceView = self.view;
//        activityViewController.popoverPresentationController.sourceRect = self.frame;
        [self presentViewController:activityViewController
                           animated:YES
                         completion:nil];
    }
    else
    {
        NSLog(@"iPhone");
        [self presentViewController:activityViewController 
                          animated:YES 
                        completion:nil];
    }

然后像图像中那样显示它:(_shareBarButton 是您希望弹出窗口从中显示的 UIBarButtonItem)

- (void)shareLeaflet
    {
        NSString *forwardedString = [[NSString alloc] initWithFormat:@"Check out this leaflet\n\n %@ \n\nself.theURLToShare];
        UIActivityViewController *activityViewController = [[UIActivityViewController alloc] initWithActivityItems:[NSArray arrayWithObjects:forwardedString, nil] applicationActivities:nil];

        if (IDIOM == IPAD)
        {
            NSLog(@"iPad");
            activityViewController.popoverPresentationController.sourceView = self.view;
    //        activityViewController.popoverPresentationController.sourceRect = self.frame;

           _popover = [[UIPopoverController alloc] initWithContentViewController:activityViewController];
           _popover.delegate = self;
           [_popover presentPopoverFromBarButtonItem:_shareBarButton permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
        }
        else
        {
            NSLog(@"iPhone");
            [self presentViewController:activityViewController 
                              animated:YES 
                            completion:nil];
        }