Android/Java网络加载框架Retrofit（二）load bitmap into ListView

package zhangphil.http;

import android.app.ListActivity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;

import java.util.ArrayList;

import okhttp3.ResponseBody;
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
import retrofit2.Retrofit;
import retrofit2.http.GET;
import retrofit2.http.Path;

public class MainActivity extends ListActivity {
    private MyRetrofitService mRetrofitService;
    private ArrayList<Call> mCalls = new ArrayList<>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        Retrofit mRetrofit = new Retrofit.Builder()
                .baseUrl("https://www.baidu.com/")
                .build();

        mRetrofitService = mRetrofit.create(MyRetrofitService.class);

        ArrayAdapter mArrayAdapter = new ArrayAdapter(this, 0) {
            @NonNull
            @Override
            public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
                ImageView imageView = new ImageView(getContext());
                setBitmap("bd_logo1.png", imageView);
                return imageView;
            }

            @Override
            public int getCount() {
                return 10;
            }
        };

        setListAdapter(mArrayAdapter);
    }

    private void setBitmap(String picName, final ImageView imageView) {
        final Call mCall = mRetrofitService.getImagesByName(picName);
        mCall.enqueue(new Callback<ResponseBody>() {
            @Override
            public void onResponse(Call<ResponseBody> call, Response<ResponseBody> response) {
                try {
                    Log.d("请求的网络链接", String.valueOf(mCall.request().url()));

                    byte[] bytes = response.body().bytes();
                    Bitmap bmp = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);

                    imageView.setImageBitmap(bmp);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }

            @Override
            public void onFailure(Call<ResponseBody> call, Throwable t) {
                t.printStackTrace();
            }
        });

        mCalls.add(mCall);
    }

    private interface MyRetrofitService {
        @GET("img/{picName}")
        Call<ResponseBody> getImagesByName(@Path("picName") String picName);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();

        for (Call call : mCalls) {
            call.cancel();
        }
    }
}