UIPopoverController 在运行 iOS 5.0.1 的 iPad 上崩溃？

Question

我在 iPad 上使用 iOS 5 上的 UIImagePickerController，但我的应用程序刚刚被拒绝，因为它崩溃了。它不会在我这边崩溃，但我确信它与 UIPopoverController 有关。

请指出任何看起来不好的地方！

显示 UIImagePickerController：

- (IBAction)photoLibraryiPad {
if (popoverController) {
    if ([self.popoverController isPopoverVisible]) {
        [self.popoverController dismissPopoverAnimated:YES];
        [popoverController setDelegate:nil];
        [popoverController release];
    }
} else {
    if ([UIImagePickerController isSourceTypeAvailable:
         UIImagePickerControllerSourceTypeSavedPhotosAlbum])
    {
        UIImagePickerController *imagePicker =
        [[UIImagePickerController alloc] init];
        imagePicker.delegate = self;
        imagePicker.sourceType =
        UIImagePickerControllerSourceTypePhotoLibrary;
        imagePicker.allowsEditing = YES;

        self.popoverController = [[UIPopoverController alloc]
                                  initWithContentViewController:imagePicker];

        popoverController.delegate = self;

        [self.popoverController presentPopoverFromRect:photolibrarybutton.frame inView:self.view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];

        [imagePicker release];
    }
}

}

然后这就是它崩溃的地方：

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {

    if ([self.popoverController isPopoverVisible]) {
    [self.popoverController dismissPopoverAnimated:YES];
    [popoverController setDelegate:nil];
    [popoverController release];
}

    [noimageAvailable setHidden:YES];
    UIImage *originalImage = (UIImage *) [info objectForKey:
                                     UIImagePickerControllerEditedImage];  
    [imgPic setImage:originalImage forState:UIControlStateNormal];
    // Hide picker selector
    [picker dismissModalViewControllerAnimated: YES];
    [picker release];

}

Answer 1

两件事：

1）当你释放弹出窗口时，你应该将委托设置为nil。在调用[popoverController release]之前，popoverController.delegate = nil。如果您尝试多次使用选择器，它也可能会崩溃。委托正在调用不再存在的对象。

2）当检查弹出窗口是否可见时，首先检查以确保它存在。