if(mMap != null && location != null){
        LatLng gps = new LatLng(location.getLatitude(),
        location.getLongitude());
        marker = mMap.addMarker(new MarkerOptions().position(gps).icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_BLUE)));
        marker.setDraggable(true);


        return marker;
    }
    return null;
}


public void drawMarker(View view) {
    if (marker == null) {
        Location loc = returnLocation();
        Double lat = loc.getLatitude();
        Double lon = loc.getLongitude();
        //para guardar un marker en sharedPreferences
        sharedPreferences.edit().putString("Lat",String.valueOf(lat)).apply();
        sharedPreferences.edit().putString("Lng",String.valueOf(lon)).apply();
        sharedPreferences.edit().putLong("time",System.currentTimeMillis()).apply();
        marker = addMarker(loc);
        dialogPlayas.dismiss();
        removeMarker.setVisibility(View.VISIBLE);

    }
}

customAdapter adapter = new customAdapter(this, imgid);
    list = (GridView) playasView.findViewById(R.id.list);
    list.setAdapter(adapter);
    list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
            listaReporte.add(list.getSelectedItem());
        }
    });
    //Log.i("Mostrando lista",listaReporte.getFirst().toString());
    addMarker = playasView.findViewById(R.id.addMarker);
    dialogPlayas = mBuilder.create();
    dialogPlayas.getWindow().setBackgroundDrawable(new ColorDrawable(android.graphics.Color.TRANSPARENT));
    dialogPlayas.show();
}