Ios 需要将.MP4文件从documents文件夹保存到Photo Gallery，但资源url返回零

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gallery，但它不起作用。它抛出的资源url为零。有人能帮我解决这个问题吗

    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");
        }
    }];

---

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");


                  }];
             }
         }];
    }

---

请尝试completionBlock中的assetURL.absoluteString

此行的日志是什么：-NSLog（@“Moview URL:%@”，movieURL）；？在这里注释这行有什么用：-NSURL*url=[movieURL copy]；url是文档目录中视频位置的资源url。您是否在变量“url”中获取任何值，然后记录它？url值是否存在file:///var/mobile/Containers/Data/Application/E0B3785E-D991-4FE3-A67A-C49A3D2DF032/Documents/test.mp4 但在WriteVideoPathToSavedPhotosalbum中，资产url为零。它也没有保存到gallery。我仍然将资产url设置为空。任何想法，可能的原因是什么。srcURL返回值，但资产值为空检查文件路径后，如果文件路径存在，则发送到saveTocamerRoll方法。我已经这样做了，它对我来说工作正常。我已经尝试了路径存在。它仍然没有保存到相册，并且资产url为null。资产显示为null，并且它没有保存到Gallery。AlassetLibrary获取图像名称的替代方案是什么？不推荐使用该库。我想获取选中的图像的名称