Get Set Screen Orientation Android Code

final String ERROR = "my error message....";

 private class DownloadWebPageTask extends AsyncTask<String, Void, String> {
// some code and method ..... see AsyncTask

       @Override
        protected String doInBackground(String... urls) {

              URL urlL = null;
                try {
                    urlL = new URL(url);//"//chmi.cz..../"
                    HttpURLConnection urlConnection = null;
                    try {
                         urlConnection = (HttpURLConnection) urlL.openConnection();
                        InputStream in = new BufferedInputStream(urlConnection.getInputStream());
                      response =  readStream(in);
                        return response;
                    } catch (IOException e) {
                        //throw new RuntimeException(e);

                    } finally {
                        if(urlConnection != null)
                            urlConnection.disconnect();
                        return ERROR;
                    }
                } catch (MalformedURLException e) {
                    e.printStackTrace();
                    return ERROR;
                }
           }
            return response;
        }

        private String readStream(InputStream is) {
            try {
                ByteArrayOutputStream bo = new ByteArrayOutputStream();
                int i = is.read();
                while(i != -1) {
                    bo.write(i);
                    i = is.read();
                }
                return bo.toString();
            } catch (IOException e) {
                return "";
            }
        }

 <activity android:name=".MainActivity"
                  android:label="@string/app_name"
                  android:configChanges="keyboardHidden|orientation|screenSize"
                  >

// Context instead Activity as a parameter
@Override
public void onAttach(Context context) {
    super.onAttach(context);

    Activity a;

    if (context instanceof Activity){
        a=(Activity) context;
    }

}

OnNoteClickedListener listener;
/* old emxample of usage
	@Override
	public void onAttach(Activity activity) {
		super.onAttach(activity);
		try {
			listener = (OnNoteClickedListener) activity;
		} catch (ClassCastException e) {
			throw new ClassCastException(activity.toString()
					+ " must implement OnNoteClickedListener");
		}
	}
*/
// new version of code
	@Override
	public void onAttach(Context context) {
		super.onAttach(context);

		Activity a;

		if (context instanceof Activity){
			a=(Activity) context;
			try {
				listener = (OnNoteClickedListener) a;
			} catch (ClassCastException e) {
				throw new ClassCastException(a.toString()
						+ " must implement OnNoteClickedListener");
			}
		}

	}

<activity android:name="com.google.android.gms.ads.AdActivity"
              android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize"
              android:theme="@android:style/Theme.Translucent" />