Android

@Override
    public void onMapReady(GoogleMap map) {

        this.infoWindow = (ViewGroup)getActivity().getLayoutInflater().inflate(R.layout.info_marker_window, null);
        this.mekanfoto = (ImageView) infowindow.findViewById(R.id.mekan_foto);
        googleMap = map;
   
        if(googleMap!=null){

            googleMap.setInfoWindowAdapter(new GoogleMap.InfoWindowAdapter() {
                @Override
                public View getInfoWindow(Marker marker) {
                    return null;
                }

                @Override
                public View getInfoContents(final Marker marker) {
                    if(mLastLocation.getLatitude()!=marker.getPosition().latitude||
                            mLastLocation.getLongitude()!=marker.getPosition().longitude){

                        customMarker = CustomMarker.getCustomMarker(listCustomMarker, marker);
                        final String URL = customMarker.getVenue().getFoto(); 
                        createThread(mekanfoto,URL).start();
                        mapWrapperLayout.setMarkerWithInfoWindow(marker, infoWindow);
                        return infoWindow;
                    }
                    return null;}
            });
        }
    }

private synchronized Thread createThread(final ImageView imageView, final String URL)
    {
        final Bitmap[] b = new Bitmap[1];
       Thread thread=new Thread(new Runnable() {
           @Override
           public void run() {
               b[0] =download_Image(URL,imageView);

           }
       });
        return thread;
    }

public Bitmap download_Image(String url,ImageView imageview) {
        //---------------------------------------------------
        URL newurl = null;

        try {
            newurl = new URL(url);
        } catch (MalformedURLException e) {
            e.printStackTrace();
        }

        Bitmap mIcon_val = null;

        try {
            URLConnection urlConnection=newurl.openConnection();
            InputStream is=urlConnection.getInputStream();
            mIcon_val= BitmapFactory.decodeStream(is);
        } catch (Exception e) {
            e.printStackTrace();
        }finally {

        }
        imageview.setImageBitmap(mIcon_val);
        return mIcon_val;

        //---------------------------------------------------
}

private boolean EverPlayedNextLevel(final int Level){
        locked = false;
        String Uid = acct.getId();
        DatabaseReference db = FirebaseDatabase.getInstance().getReference();
        Query query = db.child("levels/uid/" + Uid + "/" + Level);
        query.addListenerForSingleValueEvent(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                locked = ((long)dataSnapshot.getValue() == -1);
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {

            }
        });
        return locked;
    }

((long)dataSnapshot.getValue() == -1);

((long)dataSnapshot.getValue() == -1);