OSMDroid how to make external provider work together with local?

问题

So I've finally gotten osmdroid working with a local directory but I'd like to load tiles from Mapnik when they are missing locally. I'm not sure what I'm missing.

My implementation is as follows:

private MapView mapView = null;
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.osm_map);

    mapView = (MapView) findViewById(R.id.mapview);
    mapView.setBuiltInZoomControls(true);
    mapView.setMultiTouchControls(true);

    MapController mapController = mapView.getController();
    mapController.setZoom(5);
    GeoPoint point2 = new GeoPoint(55708545, 10006348);
    mapController.setCenter(point2);

    //TODO Save to SD
    AssetManager assetManager = getAssets();
    InputStream is;
    String fileName = "test.zip";
    String path = Environment.getExternalStorageDirectory() + File.separator + fileName;    //TODO Path to save it to
    try {
        is = assetManager.open(fileName);

        FileOutputStream fo = new FileOutputStream(path);

        byte[] b = new byte[1024];
        int length;
        while((length = is.read(b)) != -1) {
            fo.write(b, 0, length);
        }
        fo.flush();
        fo.close();
        is.close();
    } catch (IOException  e) {
        e.printStackTrace();
    }

    File tileFile = new File(path);
    IArchiveFile[] archives = new IArchiveFile[1];
    archives[0] = ArchiveFileFactory.getArchiveFile(tileFile);

    CustomTileSource customTiles = new CustomTileSource("Mapnik", null, 0, 24, 256, ".png");    // the name should match the name of the folder that is zipped

    MapTileModuleProviderBase[] providers = new MapTileModuleProviderBase[2];
    providers[0] = new MapTileFileArchiveProvider(new SimpleRegisterReceiver(getApplicationContext()), customTiles, archives);
    providers[1] =  new MapTileDownloader(TileSourceFactory.MAPNIK);
    mapView.setUseDataConnection(false);
    mapView.setTileSource(TileSourceFactory.MAPNIK);

    MapTileProviderArray tileProvider = new MapTileProviderArray(customTiles, null, providers);
    TilesOverlay tilesOverlay = new TilesOverlay(tileProvider, getApplicationContext());
    mapView.getOverlays().add(tilesOverlay);
    mapView.invalidate();
}

AND

public class CustomTileSource extends BitmapTileSourceBase {

    public CustomTileSource(String aName, string aResourceId,
            int aZoomMinLevel, int aZoomMaxLevel, int aTileSizePixels,
            String aImageFilenameEnding) {
        super(aName, aResourceId, aZoomMinLevel, aZoomMaxLevel, aTileSizePixels,
                aImageFilenameEnding);
    }

}

回答1:

Okay so I've finally found a solution. Its quite complex and long but it works :D

Now inside my OsmDroidFragment (yes map in fragment) I have following:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    RelativeLayout view = (RelativeLayout) inflater.inflate(R.layout.osm_map, container, false);
    RelativeLayout mapContainer = (RelativeLayout) view.findViewById(R.id.osm_map_parent);

    mMapView = new OsmCustomMapView(getActivity(), 256, 10, 13);    // I've made a custom implementation in order to limit zoom, you can just use regular osmdroid mapview
    LayoutParams params = new RelativeLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
    mMapView.setLayoutParams(params);
    mapContainer.addView(mMapView);

    mMapView.setBuiltInZoomControls(true);
    mMapView.setMultiTouchControls(false);  // pinch zoom works bad on osmdroid

    MapController mapController = mMapView.getController();
    mapController.setZoom(11);  // must set zoom before setCenter, else we get the wrong position
    GeoPoint center = new GeoPoint(0,0);
    mapController.setCenter(center);

    // save zip to sd
    AssetManager assetManager = getActivity().getAssets();
    InputStream is;
    String fileName = "map.zip";    // the zip file lies in assets root
    String path = this.getActivity().getExternalFilesDir(null) + File.separator + fileName; // the path I save SD to

    File tileFile = new File(path);
    if(!tileFile.exists()) {
        try {
            is = assetManager.open(fileName);

            FileOutputStream fo = new FileOutputStream(path);

            byte[] b = new byte[1024];
            int length;
            while((length = is.read(b)) != -1) {
                fo.write(b, 0, length);
            }

            fo.flush();
            fo.close();
            is.close();
        } catch (IOException  e) {
            e.printStackTrace();
        }
    }

    IArchiveFile[] archives = new IArchiveFile[1];
    archives[0] = ArchiveFileFactory.getArchiveFile(tileFile);

    // Simple implementation that extends BitmapTileSourceBase and nothing else
    CustomTileSource customTiles = new CustomTileSource("Maverik", null, 10, 14, 256, ".png");  // Maverik is the name of the folder inside the zip (so zip is map.zip and inside it is a folder called Maverik)

    MapTileModuleProviderBase[] providers = new MapTileModuleProviderBase[2];
    providers[0] = new MapTileFileArchiveProvider(new SimpleRegisterReceiver(getActivity().getApplicationContext()), customTiles, archives);    // this one is for local tiles (zip etc.)
    providers[1] =  new MapTileDownloader(TileSourceFactory.MAPNIK);    // MAPNIK web tile source

    mMapView.setUseDataConnection(true);

    MapTileProviderArray tileProvider = new MapTileProviderArray(customTiles, 
            new SimpleRegisterReceiver(getActivity().getApplicationContext()), providers);
    TilesOverlay tilesOverlay = new TilesOverlay(tileProvider, getActivity().getApplicationContext());
    tilesOverlay.setLoadingBackgroundColor(Color.TRANSPARENT);  // this makes sure that the invisble tiles of local tiles are transparent so we can see tiles from web, transparent have a minor performance decline.

    mMapView.getOverlays().add(tilesOverlay);

    mMapView.invalidate();

    return view;
}

来源：https://stackoverflow.com/questions/13270047/osmdroid-how-to-make-external-provider-work-together-with-local