ios - MBTile 及其图层问题

Question

我正在使用MBTiles我的一个应用程序。客户端给定了 1 个MBTile文件，我需要提取该 MBTile 文件并获取该 MBTile 文件中的所有图层及其图层名称我需要

我正在使用下面的代码：

NSURL *url=[NSURL fileURLWithPath:[[NSBundle mainBundle]pathForResource:@"myMBTILE" ofType:@"mbtiles"]];
    //     NSURL *url=[NSURL fileURLWithPath:[[NSBundle mainBundle]pathForResource:@"control1" ofType:@"mbtiles"]];
offlineSource=[[RMMBTilesSource alloc]initWithTileSetURL:url ];

mapView = [[RMMapView alloc] initWithFrame:_myView.bounds andTilesource:offlineSource];

mapView.delegate = self;
mapView.zoom = 2;
mapView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
mapView.adjustTilesForRetinaDisplay = YES; // these tiles aren't designed specifically for retina, so make them legible

[_myView addSubview:mapView];

我对 iOS 很陌生。请帮我