ios - 需要将 .MP4 文件从文档文件夹保存到照片库，但 Assets url 返回 nil

Question

我已将 .mp4 文件从服务器下载到文档目录并调用
writeVideoAtPathToSavedPhotosAlbum 方法保存到画廊，但它也不工作。它抛出 Assets url nil。任何人都可以帮助我解决这个问题

    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *path = [documentsDirectory stringByAppendingPathComponent:@"test.mp4"];
    NSURL *movieURL = [NSURL fileURLWithPath:path];
    ALAssetsLibrary* library = [[ALAssetsLibrary alloc] init];
    NSLog(@"Moview URL:%@",movieURL);
    NSURL *url = [movieURL copy];

    [library writeVideoAtPathToSavedPhotosAlbum:url
                                completionBlock:^(NSURL *assetURL, NSError *error)
    {
        NSLog(@"Asset Url:%@",assetURL);
        if(!error) {
            NSLog(@"\t ! Error");
            NSLog(@"\t Error: %@", [error localizedDescription]);
            NSLog(@"\t Error code %d", [error code]);
        }

        if(error != nil) {
            NSLog(@"\t ERROR != NIL");
            NSLog(@"\t Error - Image Failed To Save With Error: %@", [error localizedDescription]);
            NSLog(@"\t Error code %d", [error code]);
        }

        if(error == nil) {
            NSLog(@"\t ERROR == NIL");
        }
    }];

Answer 1

检查以下方法:

  -(void)ButtonAction:(id)sender
    {
        NSURL *video = [NSURL URLWithString:YOURURL];
        NSData *data = [NSData  dataWithContentsOfURL:video];
        NSString *docDirPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
        NSString *filePath = [NSString stringWithFormat:@"%@/myvideo_%@.mp4",docDirPath,CURRENT_TIMESTAMP];
        [data writeToFile:filePath atomically:YES];

        NSURL *urlPath  = [[NSURL alloc] initFileURLWithPath:filePath];
        [self saveToCameraRoll:urlPath dict:(NSDictionary *)sender];
    }

    -(void) saveToCameraRoll:(NSURL *)srcURL dict:(NSDictionary *)dictValues
    {
        NSLog(@"srcURL: %@", srcURL);

        ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
        [library writeVideoAtPathToSavedPhotosAlbum:srcURL completionBlock:^(NSURL *assetURL, NSError *error)
         {
             NSURL *savedAssetURL = assetURL;

             NSLog(@"asset url %@",assetURL);
             if(error)
             {
                error handling
             }
             else
             {
                 [library assetForURL:savedAssetURL resultBlock:^(ALAsset * alAsset)
                  {
                             NSLog(@"Saved");


                  }failureBlock:^(NSError *error)
                  {
                               NSLog(@"Not Saved");


                  }];
             }
         }];
    }