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Run SelectorInBackground, notify another viewcontroller when it's done

I have a method used to save an image when the user clicks the "Save" button. I use the performSelectorInBackground function to save the image, the view manager opens and the previous view manager is displayed.

I want the table (on the previous UIViewController) to reload its data when image processing is in progress.

How can i do this?

The save method is called as follows:

[self performSelectorInBackground:@selector(saveImage) withObject:nil];
[self.navigationController popViewControllerAnimated:YES];
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3 answers

saveImage . - :

// post notification
    [[NSNotificationCenter defaultCenter] postNotificationName:@"ImageSaved" object:nil];

, ,

- (void) imageSaved:(NSNotification *)notification{

    [self.tableView reloadData];

}

viewDidLoad :

[[NSNotificationCenter defaultCenter] addObserver:self
                                selector:@selector(imageSaved:)
                                                 name:@"ImageSaved" object:nil];

, dealloc,

[[NSNotificationCenter defaultCenter] removeObserver:self];
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, - saveImage. , -

[self performSelectorInBackground:@selector(saveImage) withObject:previousView];

saveImage, , .

@protocol processingFinishedDelegate
-(void)processingFinished;
@end

, saveImage :

[(id<processingFinishedDelegate>)object processingFinished];

, , previousView .

+2

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