如何在 android 中保存 google 地图?以及如何使用 tileprovider

How to save google map in android ?and How to use tileprovider

我正在使用互联网创建 Android Google 地图,但我不知道如何在 Android 应用程序中保存 Google 地图。
示例:Android 地图应用。

请帮帮我

你可以试试static maps, you can save your map as image. Also user can save offline maps on his own: downloading offline maps.

代码示例:

public Bitmap getBitmap() {
    Bitmap bmp = null;
    try {
        List<LatLng> places = getPlaces();
        String mapUrl = "https://maps.googleapis.com/maps/api/staticmap?size=600x600&maptype=roadmap"; 
        for (LatLng place : places) {
            mapUrl += "&markers=" + place.latitude + "," + place.longitude;
        }

        InputStream in = new URL(mapUrl).openStream();
        bmp = BitmapFactory.decodeStream(in);
    } catch (Exception ex) {
        // log error
    }
    return bmp;
}

您可以抓取来自不同来源的磁贴。这是 TileProvider 的实现,您可以将其与 googleMap 一起使用,从而获取 GoogleMapTiles

   public class GoogleMapOfflineTileProvider implements TileProvider
    {

        private static final String UPPER_ZOOM_TILE_URL;


        static
        {

            UPPER_ZOOM_TILE_URL = "http://mt0.google.com/vt/lyrs=m&hl=ru&x=%d&y=%d&z=%d&scale=1&s=Galileo";
        }


        private static final String TAG = GoogleMapOfflineTileProvider.class.getName();

        private SQLiteMapDatabase sqLiteMapDatabase;


        public GoogleMapOfflineTileProvider(File file)
        {
            this(file.getAbsolutePath());
        }


        public GoogleMapOfflineTileProvider(String pathToFile)
        {
            sqLiteMapDatabase = new SQLiteMapDatabase();
            sqLiteMapDatabase.setFile(new File(pathToFile));
        }


        @Override
        public Tile getTile(int x, int y, int z)
        {
            Tile tile = NO_TILE;

                if ( sqLiteMapDatabase.existsTile(x, y, z) )
                {
                    tile = new Tile(256, 256, sqLiteMapDatabase.getTile(x, y, z));
                }
                else if ( z < 11 )
                {
                    ByteArrayOutputStream stream = new ByteArrayOutputStream();
                    getBitmapFromURL(x, y, z).compress(Bitmap.CompressFormat.JPEG, 100, stream);
                    tile = new Tile(256, 256, stream.toByteArray());
                }

            return tile;
        }


    public static Bitmap getBitmapFromURL(int x, int y, int z)
    {
        Log.d(TAG, String.format(UPPER_ZOOM_TILE_URL, x, y, z));
        try
        {
            URL url = new URL(String.format(UPPER_ZOOM_TILE_URL, x, y, z));
            HttpURLConnection connection = (HttpURLConnection)url.openConnection();
            connection.setDoInput(true);
            connection.connect();
            return BitmapFactory.decodeStream(connection.getInputStream());
        }
        catch (IOException e)
        {
            Log.d(TAG, "exception when retrieving bitmap from internet" + e.toString());
            return null;
        }
    }
}

因此您可以通过 x/y 和缩放将切片缓存到您的数据库中。或者您可以保存特定区域。在重用它们之后。要为 google 个地图设置它,请使用:

tileProvider = new GoogleMapOfflineTileProvider(file);
offlineOverlay = googleMap.addTileOverlay(new TileOverlayOptions().tileProvider(tileProvider).zIndex(3000));

重要提示:根据google许可协议,您只能暂时在移动设备上使用这种缓存。