如何使用Google Maps v2快照？

Question

我必须用新的"快照制造商"来解决这个问题,这是在谷歌地图发布8月份实施但我不知道如何做到这一点.可以给我一个简单的例子吗？

这是我的代码:

public class MainActivity extends Activity {
static LatLng HAMBURG = new LatLng(47.524749, 21.632745);
GoogleMap map;
File dbFile;
private File imageFile;


@SuppressLint("NewApi")
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    PolylineOptions line = new PolylineOptions();

    map = ((MapFragment) getFragmentManager().findFragmentById(R.id.map))
            .getMap();
    /*
     * Adatbázis
     */
    try {
        dbFile = getDatabasePath("/mnt/sdcard/Download/TeleSensors.db");
    } catch (Exception e) {

    }

    SQLiteDatabase myDataBase = SQLiteDatabase.openDatabase(
            dbFile.getAbsolutePath(), null, SQLiteDatabase.OPEN_READONLY);

    Cursor curTAB = myDataBase.rawQuery("SELECT * FROM  GPS_Values;", null);

    Integer count = 0;
    while (curTAB.moveToNext()) {
        String s_latitude = curTAB.getString(1);
        String s_longitude = curTAB.getString(2);
        count++;
        double latitude = Double.parseDouble(s_latitude);
        double longitude = Double.parseDouble(s_longitude);
        line.add(new LatLng(latitude, longitude));

        Log.i("Coordinates",
                s_latitude.toString() + " --- " + s_longitude.toString());

    }
    curTAB.close();
    myDataBase.close();
    // adatbázis vége

    map.addPolyline(line);

    // map.setMapType(GoogleMap.MAP_TYPE_HYBRID);
    // map.setMapType(GoogleMap.MAP_TYPE_NONE);
    map.setMapType(GoogleMap.MAP_TYPE_NORMAL);
    // map.setMapType(GoogleMap.MAP_TYPE_SATELLITE);
    // map.setMapType(GoogleMap.MAP_TYPE_TERRAIN);

    // Move the camera instantly to hamburg with a zoom of 15.
    map.moveCamera(CameraUpdateFactory.newLatLngZoom(HAMBURG, 15));

    // Zoom in, animating the camera.
    map.animateCamera(CameraUpdateFactory.zoomTo(15), 2000, null);  


}

}

谢谢你非常好!

Answer 1

你必须在一个按钮监听器中调用谷歌地图快照方法,因为如果你应该过早地使用它,它会给你错误bitmap width has to be larger than 0或类似的东西.这是代码

private void button_listener() {
        Button button = (Button) findViewById(R.id.button1);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                SnapshotReadyCallback callback = new SnapshotReadyCallback() {
                    Bitmap bitmap;

                    @Override
                    public void onSnapshotReady(Bitmap snapshot) {
                        bitmap = snapshot;
                        try {
                            FileOutputStream out = new FileOutputStream("/mnt/sdcard/Download/TeleSensors.png");
                            bitmap.compress(Bitmap.CompressFormat.PNG, 90, out);
                        } catch (Exception e) {
                            e.printStackTrace();
                        }
                    }
                };

                map.snapshot(callback);
            }
        });
    }

Answer 2

这个更好,它在拍摄快照之前等待你的地图完全渲染.

它于2013年10月31日更新.

mMap.setOnMapLoadedCallback(new GoogleMap.OnMapLoadedCallback() {
    public void onMapLoaded() {
        mMap.snapshot(new GoogleMap.SnapshotReadyCallback() {
            public void onSnapshotReady(Bitmap bitmap) {
                // Write image to disk
                FileOutputStream out = new FileOutputStream("/mnt/sdcard/map.png");
                bitmap.compress(Bitmap.CompressFormat.PNG, 90, out);
            }
        });
    }
});

摘自http://googlegeodevelopers.blogspot.sg/2013/10/ghost-markers-in-your-neighborhood-new.html

Answer 3

当点击按钮拍摄谷歌地图快照时，尝试像这样使用Kotlin Android：

val snapshotReadyCallback : GoogleMap.SnapshotReadyCallback = GoogleMap.SnapshotReadyCallback { selectedScreenShot ->
    ivMapPreview.setImageBitmap(selectedScreenShot);
}

val onMapLoadedCallback : GoogleMap.OnMapLoadedCallback = GoogleMap.OnMapLoadedCallback {
    mMap!!.snapshot(snapshotReadyCallback)
}

mMap!!.setOnMapLoadedCallback(onMapLoadedCallback)

成功的。