How to save the live/animated wallpaper - ios

Question

I am making an app of live photo/wallpaper. I am downloading image and .mov file from server. Now I am stuck to saving these files in document directory. How can I store the live wallpaper in document directory. Is anyone have idea about this please tell me. Here is my code
SDWebImageDownloader *downloader = [SDWebImageDownloader sharedDownloader];
[downloader downloadImageWithURL:[NSURL URLWithString:imgFile]
options:0
progress:nil completed:^(UIImage *image, NSData *data, NSError *error, BOOL finished) {
if (image && finished) {
NSArray *searchPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentPath = [searchPaths objectAtIndex:0];
NSString* photoPath = [documentPath stringByAppendingPathComponent:[NSString stringWithFormat:#"%#.JPG",strImg]];
[data writeToFile:photoPath atomically:YES];
}
}];
NSURL *URL = [NSURL URLWithString:str];
NSURLRequest *request = [NSURLRequest requestWithURL:URL];
NSURLSessionDownloadTask *downloadTask = [manager downloadTaskWithRequest:request progress:^(NSProgress * downloadProgress){
NSLog(#"%f",downloadProgress.fractionCompleted);
NSString * str = [NSString stringWithFormat:#"%.2f",downloadProgress.fractionCompleted];
NSDictionary * infoDict = #{#"Download": str,
#"id":uniqId};
[[NSNotificationCenter defaultCenter]
postNotificationName:#"DownloadNotification"
object:self userInfo:infoDict];
}destination:^ NSURL *(NSURL *targetPath, NSURLResponse *response) {
NSArray *searchPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentPath = [searchPaths objectAtIndex:0];
NSString* videoPath = [documentPath stringByAppendingPathComponent:[NSString stringWithFormat:#"%#.MOV",strImg]];
NSURL *videoUrl =[NSURL URLWithString:videoPath];
NSLog(#"%#",[videoUrl URLByAppendingPathComponent:videoPath]);
return videoUrl;
} completionHandler:^(NSURLResponse* response, NSURL *filePath, NSError *error) {
if(error)
{
NSLog(#"File Not Dowloaded %#",error);
[self downloadFile];
}
else {
NSLog(#"%#",filePath);
[self.downloadRecord removeObjectAtIndex:0];
if (self.downloadRecord.count > 0) {
[self downloadFile];
}
}
}];

Answer 1

There's no official way to set the wallpaper programatically (or add an image/video to the list of wallpapers) from the inside an app. The closest you can achieve would be saving it to the camera role and then letting the user setting it as a wallpaper from there.
However, I believe Apple have used a private API to achieve this in some of their advertisements, however this isn't documented and using it would cause your app to be rejected from the app store approval.