gistfile1.m

- (void) savePost:(id)sender {
    
    self.post.postTitle = self.titleField.text;
    self.post.postBody = self.bodyTextView.text;
    
    [self.post saveObjectWithCompletion:^(id object, NSError *error) {
                
                if (error == nil) {
                    
                    NSLog(@"object saved");
                    self.post = object;
                    
                    [[NSNotificationCenter defaultCenter] postNotificationName:@"POST_UPDATED"
                                                                        object:nil];
                    [self.navigationController popViewControllerAnimated:YES];
                    
                }
                else {
                    
                    NSLog(@"error in updating %@", error);
                    
                }
                
            }];
    
}