image not loading from URL in custom infoWindow us

I am trying to load an image from the URL in custom infoWindow when the user click on the marker. I was able to load the other details but the image is not loading int it. i'm using Picasso library to do this for me. I have search many related topics and see the solutions but was not able to understand which solution to apply to solve my problem. I am using an web service call to get the required data.

This is my code:

  @Override
        public View getInfoContents(Marker arg0) {

            //marker.showInfoWindow();
            return null;
        }

        @Override
        public View getInfoWindow(Marker arg0) 
        {

            View v = getLayoutInflater().inflate(R.layout.map_infowindow, null);


             for(int i=0 ; i<lstMain.size();i++)
                {
                    Pojo b=lstMain.get(i);
                    double slat= Double.parseDouble(b.getLatitude());
                    double slng= Double.parseDouble(b.getLongitude());

                    double lat= Math.round(slat*100000.0)/100000.0;
                    double lng= Math.round(slng*100000.0)/100000.0;

                    String s1=String.valueOf(lat);
                    String s2=String.valueOf(lng);

                    Log.v("comparing latilongi pojo===>", lat+" , "+lng);
                    Log.v("comparing latilongi marker===>", Clickedlatitude+" , "+Clickedlongitude);

                    if(s1.equals(String.valueOf(Clickedlatitude)) && s2.equals(String.valueOf(Clickedlongitude)))
                    {
                        txtDname=(TextView)v.findViewById(R.id.infoDoctorName);
                        txtDspe=(TextView)v.findViewById(R.id.infoDoctorSpe);
                        txtDaddress=(TextView)v.findViewById(R.id.infoDoctorAddress);
                        imgUrl=(ImageView)v.findViewById(R.id.infoDoctorImage);
                        String url=b.getPhotoURL();

                        txtDname.setText(b.getDoctorName());
                        txtDspe.setText(b.getSpecialization());
                        txtDaddress.setText(b.getAddress1()+" , "+b.getAddress2());


                        Picasso.with(MapActivity.this)
                        .load(url)
                        .placeholder(R.drawable.ic_launcher)
                        .error(R.drawable.ic_launcher).resize(50, 50)
                        .into(imgUrl);


                    }

                }
            return v;
        }

I have already seen these solutions, But not understanding exactly what will solve my problem:

Why Custom InfoWindow of google map v2 ,Not load url Image?

Android Google maps APIv2 InfoWindow and Markers

Add an Image from url into custom InfoWindow google maps v2

You can use a Picasso Callback onsuccess loading the image, like this

if (image != null) {
   Picasso.with(getApplicationContext())
          .load(image)
          .placeholder(R.drawable.ic_launcher)
          .into(i, new MarkerCallback(marker));
}

and create a new class to handle the Picasso Callback like this MarkerCallback.java

public class MarkerCallback implements Callback {
   Marker marker=null;

   MarkerCallback(Marker marker) {
     this.marker=marker;
   }

   @Override
   public void onError() {
     Log.e(getClass().getSimpleName(), "Error loading thumbnail!");
   }

   @Override
   public void onSuccess() {
     if (marker != null && marker.isInfoWindowShown()) {
       marker.hideInfoWindow();
       marker.showInfoWindow();
     }
   }
}