iOS共享扩展名未获取图像

Question

I am sure this is trivial once someone kindly point me in the right direction so my apology for asking a silly question. However I have been searching for days I can't figure out what I am doing wrong.

Scenario: create a simple share extension that receives an image file

Problem: when I access the attachements, the handler is never called albeit I can see the "public.jpg" in the itemProvider but I can't see where the data would be?

What I have done:

1) defined NSExtensionActivationSupportsImageWithMaxCount = 1 as my only activation rule
2) added CoreMedia framework to the extension
3) added the same group to both app and app extension
4) made sure both have the group (1) in the entitlement
5) made sure both are using a certificate/app id with that group enabled
6) clean and rebuild several times to no avail.

The code:

- (void)didSelectPost {
/
for (NSExtensionItem *item in self.extensionContext.inputItems) {
    for (NSItemProvider *itemProvider in item.attachments) {
        if ([itemProvider hasItemConformingToTypeIdentifier:(NSString *)kUTTypeImage]) {
I can hit this breakpoint --> [itemProvider loadItemForTypeIdentifier:(NSString *)kUTTypeImage options:nil completionHandler:^(UIImage *image, NSError *error) {
but not this one --> photo = image;
            }];
            break;
        }
    }
}
.... and so on and so forth

Answer 1

You haven't posted your complete code but I suspect that you are calling completeRequestReturningItems:completionHandler: at the wrong location:

WRONG :

- (void)didSelectPost {
        NSExtensionItem *item = self.extensionContext.inputItems.firstObject;
        NSItemProvider *itemProvider = item.attachments.firstObject;
        if ([itemProvider hasItemConformingToTypeIdentifier:(NSString *)kUTTypeImage]) {
            [itemProvider loadItemForTypeIdentifier:(NSString *)kUTTypeImage
                                            options:nil
                                  completionHandler:^(NSURL *url, NSError *error) {
                                      // send the image
                                  }];
        }
        // ↓ this is the wrong location ↓
        [self.extensionContext completeRequestReturningItems:@[] completionHandler:nil];
    }

The problem is that calling completeRequestReturningItems:completionHandler: immediately dismisses the ShareViewController and deallocates it. So the NSItemProvider that contains the image is also destroyed before it can access the image (because it loads its items asynchronously). In other words: the completion handler in which you send the image to your server is never called, because the whole shareViewController has already been deallocated.

To fix that problem you have to move the call to completeRequestReturningItems:completionHandler: to the end of the completion handler AFTER you send the image.

CORRECT:

- (void)didSelectPost {
    NSExtensionItem *item = self.extensionContext.inputItems.firstObject;
    NSItemProvider *itemProvider = item.attachments.firstObject;
    if ([itemProvider hasItemConformingToTypeIdentifier:(NSString *)kUTTypeImage]) {
        [itemProvider loadItemForTypeIdentifier:(NSString *)kUTTypeImage
                                        options:nil
                              completionHandler:^(NSURL *url, NSError *error) {
                                  // send the image
                                  [self.extensionContext completeRequestReturningItems:@[]         
                                                                     completionHandler:nil];
                              }];
    }
}