How to create osmdroid XYTileSource for offline tiles in version 4.1?

问题

I have offline osmdroid maps working using version 4.0. Upgrading to 4.1, they no longer work. I have narrowed the problem down to the XYTileSource, in which aBaseUrl changed from being a string in 4.0 to and array in 4.1. How do I get offline tiles to work in 4.1?

Old 4.0 code that worked. The tiles are in /sdcard/osmdroid/tiles.zip

XYTileSource ts = new XYTileSource ( "tiles", 
                                      ResourceProxy.string.offline_mode, 
                                      13, 
                                      17, 
                                      256,
                                      ".png",
                                      "http://127.0.0.1");

mapView = (MapView) findViewById(R.id.mapview);
mapView.setTileSource(ts); 
mapView.setMultiTouchControls(true);
mapView.setBuiltInZoomControls(false);
mapView.setUseDataConnection(false); 
mapView.getController().setZoom(15);
GeoPoint point = new GeoPoint(40.715,-73.945);
mapView.getController().setCenter(point);

I tried changing it to this, but it doesn't work.

String[] urls = {"http://127.0.0.1"};
XYTileSource ts = new XYTileSource ( "tiles", 
                                      ResourceProxy.string.offline_mode, 
                                      13, 
                                      17, 
                                      256,
                                      ".png",
                                      urls);

回答1:

I tried to provide a full answer here: Download maps for osmdroid

If you have an "old" tiles.zip, open it, and check:

the root directory name => put it as the "aName" of XYTileSource constructor (is it really "tiles"?)
the tiles images extension => put it as the aImageFileNameEnding (is it really ".png"?)

The aResourceId and aBaseUrl params are not used for zip files.

回答2:

I see that you are using XYTileSource, which by default extends OnlineTileSourceBase.

I have found a workaround for the Url issue, by creating a CustomTileSource class. Something like below:

public class CustomTileSource extends OnlineTileSourceBase {

public static String[] TILE_URL = {"my_url"};

//constructor is default - I changed nothing here
    public CustomTileSource (String aName, string aResourceId, int aZoomMinLevel, int aZoomMaxLevel,
            int aTileSizePixels, String aImageFilenameEnding, String[] url) {
        super(
                aName,
                aResourceId,
                aZoomMinLevel,
                aZoomMaxLevel,
                aTileSizePixels,
                aImageFilenameEnding,
                url);
        // TODO Auto-generated constructor stub
    }

    /**
     * returns the url for each tile, depending on zoom level
     */
    //this is where I changed the return statement to take the first url from the string array of urls
    @Override
    public String getTileURLString(MapTile aTile) {
        return TILE_URL[0] + aTile.getX() + "+" + aTile.getY() + "+" + aTile.getZoomLevel();
    }
}

In my code, where I need to instantiate the tilesource, I use:

 CustomTileSource  tileSource = new CustomTileSource ("Default", ResourceProxy.string.offline_mode, MIN_ZOOM_LVL, MAX_ZOOM_LVL, DEFAULT_TILE_SIZE, TILE_FORMAT, CustomTileSource.TILE_URL);
//MIN_ZOOM_LVL, MAX_ZOOM_LVL, DEFAULT_TILE_SIZE, TILE_FORMAT are constants that I defined elsewhere

Hope it helps.

来源：https://stackoverflow.com/questions/22842624/how-to-create-osmdroid-xytilesource-for-offline-tiles-in-version-4-1

标签

android

offline

osmdroid