使用FB SDK在iOS上共享视频

Question

I am very new to programming in iOS and therefore, the question might seem rather stupid but I really do not know what is wrong.

So, I was following sharing in iOS on the https://developers.facebook.com/docs/sharing/ios and I was successful in sharing link, and photo. But I have no idea why I cannot share a video. I am not using UIImagePickerControllerReferenceURL but instead, I am using [[NSBundle mainBundle] URLForResource:@"xyz" withExtension:@"mp4"] for the videoURL .
Is this the reason why the sharing button doesn't work?

My aim is to let users share content from the app directly. So I do not want them to use UIImagePickerControllerReferenceURL .
Here is the code:

NSURL* videoURL = [[NSBundle mainBundle] URLForResource:@"xyz" withExtension:@"mp4"];
FBSDKShareVideo *video = [[FBSDKShareVideo alloc] init];
video.videoURL = videoURL;
FBSDKShareVideoContent *content = [[FBSDKShareVideoContent alloc] init];
content.video = video;

FBSDKShareButton *button = [[FBSDKShareButton alloc] init];
button.center = self.view.center;
button.shareContent = content;
[self.view addSubview:button];

And file xyz.mp4 is in a Media Folder.

Answer 1

NSURL* videoURL = [[NSBundle mainBundle] URLForResource:@"xyz" withExtension:@"mp4"];

replace with this

NSURL* videoURL = [[NSBundle mainBundle] URLForResource:@"xyz" ofType:@"mp4"];

[self saveToPhotoAlbum:videoURL];

After that save this video to photo library as Facebook required asset library url.

-(void)saveToPhotoAlbum:(NSURL*)url
{
NSLog(@"srcURL: %@", url);

    ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
    ALAssetsLibraryWriteVideoCompletionBlock videoWriteCompletionBlock =
    ^(NSURL *newURL, NSError *error) {
        if (error) {
            NSLog( @"Error writing image with metadata to Photo Library: %@", error );
        } else {
            NSLog( @"Wrote image with metadata to Photo Library %@", newURL.absoluteString);
            url_new  = newURL;
        }
    };

    if ([library videoAtPathIsCompatibleWithSavedPhotosAlbum:url])
    {
        [library writeVideoAtPathToSavedPhotosAlbum:url
                                    completionBlock:videoWriteCompletionBlock];
    }
}

then

FBSDKShareDialog *shareDialog = [[FBSDKShareDialog alloc] init];    
NSURL *videoURL = url_new;
FBSDKShareVideo *video = [[FBSDKShareVideo alloc] init];
video.videoURL = videoURL;
FBSDKShareVideoContent *content = [[FBSDKShareVideoContent alloc] init];   
content.video = video;
shareDialog.shareContent = content;
shareDialog.delegate = self;
[shareDialog show];