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Re: What does keyword 'this' refer to in the following code?

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On Tuesday, April 12, 2016 at 3:03:56 PM UTC-7, Jeff Higgins wrote:
> On Mon, 11 Apr 2016 21:44:21 -0700, cdalten wrote:
> 
> > https://developers.google.com/maps/documentation/android-api/
> > 
> > Does 'this' refer to refer to the instance of MapPane or Activity?
> 
> It refers to the instance of MapPane as an
> com.google.android.gms.maps.OnMapReadyCallback
> 
> 
> import com.google.android.gms.maps.*;
> import com.google.android.gms.maps.model.*;
> import android.app.Activity;
> import android.os.Bundle;
> 
> public class MapPane extends Activity implements OnMapReadyCallback {
> 
> @Override
> protected void onCreate(Bundle savedInstanceState) {
> 
>   /*
>    * From the android.app.Activity javadoc:
>    * Derived classes must call through to the super class's 
>    * implementation of this method. If they do not,
>    * an exception will be thrown.
>    */
>   super.onCreate(savedInstanceState);
> 
>   setContentView(R.layout.map_activity);
> 
>   MapFragment mapFragment = (MapFragment) getFragmentManager()
>     .findFragmentById(R.id.map);
> 
>   /*
>    * MapFragment.getMapAsync (OnMapReadyCallback callback)
>    * 
>    * public interface OnMapReadyCallback {
>    *   abstract void onMapReady(GoogleMap googleMap)
>    * }
>    *
>    * So here, "this" refers to this instance of MapPane
>    * as an com.google.android.gms.maps.OnMapReadyCallback
>    */
>   mapFragment.getMapAsync(this);
> }
> 
> 
>   /*
>    * Implementing com.google.android.gms.maps.OnMapReadyCallback
>    */
> @Override
> public void onMapReady(GoogleMap map) {
>   LatLng sydney = new LatLng(-33.867, 151.206);
> 
>   map.setMyLocationEnabled(true);
>   map.moveCamera(CameraUpdateFactory.newLatLngZoom(sydney, 13));
> 
>   map.addMarker(new MarkerOptions()
>     .title("Sydney")
>     .snippet("The most populous city in Australia.")
>   .position(sydney));
> }
> }

I have another question. What's the significance of map.addMarker().title().snippet().position()?

Why not just do something like
map.addMarker()
map.title()
map.snippet()
map.position()
?

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What does keyword 'this' refer to in the following code? cdalten@gmail.com - 2016-04-11 21:44 -0700
  Re: What does keyword 'this' refer to in the following code? Jukka Lahtinen <jtfjdehf@hotmail.com.invalid> - 2016-04-12 12:16 +0300
  Re: What does keyword 'this' refer to in the following code? Eric Douglas <e.d.programmer@gmail.com> - 2016-04-12 04:57 -0700
    Re: What does keyword 'this' refer to in the following code? cdalten@gmail.com - 2016-04-12 08:28 -0700
      Re: What does keyword 'this' refer to in the following code? Lew <lewbloch@gmail.com> - 2016-04-12 14:03 -0700
        Re: What does keyword 'this' refer to in the following code? cdalten@gmail.com - 2016-04-12 18:23 -0700
          Re: What does keyword 'this' refer to in the following code? Jukka Lahtinen <jtfjdehf@hotmail.com.invalid> - 2016-04-13 11:39 +0300
          Re: What does keyword 'this' refer to in the following code? Eric Douglas <e.d.programmer@gmail.com> - 2016-04-13 05:07 -0700
  Re: What does keyword 'this' refer to in the following code? Jeff Higgins <jeff@invalid.invalid> - 2016-04-12 22:00 +0000
    Re: What does keyword 'this' refer to in the following code? cdalten@gmail.com - 2016-04-12 20:03 -0700
      Re: What does keyword 'this' refer to in the following code? cdalten@gmail.com - 2016-04-12 21:01 -0700
      Re: What does keyword 'this' refer to in the following code? Lars Enderin <lars.enderin@telia.com> - 2016-04-13 10:58 +0200
      Re: What does keyword 'this' refer to in the following code? Eric Douglas <e.d.programmer@gmail.com> - 2016-04-13 05:12 -0700

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