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Android Build a Weather App (2015) Concurrency and Error Handling Building an Alert Dialog

Hi there, i just have a question

I have no issue with my code, i was just curious as to how does the builder.create() function. The reason i'm curious is i haven't specified a builder have i? Isn't builder a nesting class within the AlertDialog class? so how does the builder know what it's creating? If anyone could clarify i would be very grateful :-)

AlertDialogFragment.java
import android.content.Context;
import android.os.Bundle;

public class AlertDialogFragment extends DialogFragment {

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        Context context = getActivity();

        // Insert code here!
        AlertDialog.Builder builder = new AlertDialog.Builder(context).setTitle("Sorry!")
          .setMessage("Try again!")
          .setPositiveButton("OK", null);

      AlertDialog = new builder.create;
      return dialog;
    }
}
MovieActivity.java
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import java.io.IOException;

public class MovieActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_movie);

        // Get some movie information!
        String apiUrl = "http://api.rottentomatoes.com/api/public/v1.0/movies.json?apikey=xyz&q=hobbit";
        OkHttpClient client = new OkHttpClient();
        Request request = new Request.Builder()
                .url(apiUrl)
                .build();

        Call call = client.newCall(request);
        call.enqueue(new Callback() {
            @Override
            public void onFailure(Request request, IOException e) {

            }

            @Override
            public void onResponse(Response response) throws IOException { }
        });
    }
}

1 Answer

J.D. Sandifer
J.D. Sandifer
18,813 Points

I think your confusion may stem from various items all being called "builder" - the object reference builder and the other Builder names.

The important point is that in the AlertDialog = new builder.create; line that you mention, the create() method is part of the object referenced by builder. Thus it "knows" because it's got access to all of the objects info, being part of the object itself.

Ah i understand now, thank you!