Instagram accesstoken (sample)

InstaModel

public class InstaModel {
  public static final String CLIENT_ID = "31f1cc932c264e5da2711ad437753c78";
  public static final String CLIENT_SECRET = "3db8f5ff74474cadba35a6a2bf518b5d";
  public static final String CALLBACK_URL = "https://medium.com/@vutiendunguit";
  public static final String GRANT_TYPE = "authorization_code";

  public static final String AUTH_URL = "https://api.instagram.com/oauth/authorize/";
  public static final String TOKEN_URL = "https://api.instagram.com/oauth/access_token";
  public static final String API_URL = "https://api.instagram.com/v1";

  private static final String TAG = InstaModel.class.getSimpleName();
  private AppPreference appPreference;
  private InstaService instaService;
  public InstaModel(AppPreference appPreference, InstaService instaService) {
    this.appPreference = appPreference;
    this.instaService = instaService;
  }
  public interface ResponseListener<T>{
    void onSuccess(T data);
    void onError(String message);
  }
  public Observable<AccessToken> getAccessToken(String code){
    return instaService.getAccessToken(CLIENT_ID, CLIENT_SECRET, GRANT_TYPE, CALLBACK_URL, code)
        .doOnNext(accessToken -> appPreference.storeAccessToken(accessToken));
  }

  public Observable<List<UserDetail>> findUsersFromLocation(LatLng latLng){
    final String accessToken = appPreference.getAccessToken();
    return instaService.searchMedia(10.815157, 106.695171 /*latLng.latitude, latLng.longitude*/, accessToken, 5)
        .flatMap((Media media) -> instaService.getUserDetail(media.user.getId(), accessToken))
        .toList()
        .toObservable();
  }

}

LoginFragment

public class LoginFragment extends DaggerFragment<MainComponent> {

  @BindView(R.id.webview) WebView webview;
  @BindView(R.id.loading) ProgressBar loading;
  private String mAuthUrl;
  private String mTokenUrl;
  @Inject InstaModel instaModel;
  private Callback callback;

  private final String TAG = LoginFragment.class.getSimpleName();

  @Override protected int layoutResId() {
    return R.layout.fragment_login;
  }

  @Override public void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    daggerComponent().inject(this);
    mTokenUrl = InstaModel.TOKEN_URL + "?client_id=" + InstaModel.CLIENT_ID + "&client_secret="
        + InstaModel.CLIENT_SECRET + "&redirect_uri=" + InstaModel.CALLBACK_URL + "&grant_type=authorization_code";
    mAuthUrl = InstaModel.AUTH_URL + "?client_id=" + InstaModel.CLIENT_ID + "&redirect_uri="
        + InstaModel.CALLBACK_URL + "&response_type=code&display=touch&scope=public_content+likes+comments+relationships";
  }

  @Override public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);

    callback = (Callback)getActivity();

    CookieManager cookieManager = CookieManager.getInstance();
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
      Log.i(TAG, "REMOVING COOKIES");
      cookieManager.removeAllCookies(null);
      CookieManager.getInstance().flush();
    }else{
      cookieManager.removeAllCookie();
    }

    webview.setVerticalScrollBarEnabled(false);
    webview.setHorizontalScrollBarEnabled(false);
    webview.setWebViewClient(new OAuthWebViewClient());
    webview.getSettings().setJavaScriptEnabled(true);
    webview.loadUrl(mAuthUrl);
  }


  private class OAuthWebViewClient extends WebViewClient {

    @Override public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {
      Log.d(TAG, "Redirecting URL " + view.getUrl());
      return super.shouldOverrideUrlLoading(view, request);
    }

    @Override
    public void onReceivedError(WebView view, WebResourceRequest request, WebResourceError error) {
      super.onReceivedError(view, request, error);
      Log.d(TAG, "Page error: ");
      showAlertError("Received error");
    }

    @Override
    public void onReceivedError(WebView view, int errorCode,
        String description, String failingUrl) {
      Log.d(TAG, "Page error: " + description);

      super.onReceivedError(view, errorCode, description, failingUrl);
      showAlertError(description);

    }

    @Override
    public void onPageStarted(WebView view, String url, Bitmap favicon) {
      Log.d(TAG, "Loading URL: " + url);
      super.onPageStarted(view, url, favicon);
      if (url.startsWith(InstaModel.CALLBACK_URL)) {
        String urls[] = url.split("=");
        getAccessTokenFromCode(urls[1]);
      }
      showLoading(true);
    }

    @Override
    public void onPageFinished(WebView view, String url) {
      super.onPageFinished(view, url);
      Log.d(TAG, "onPageFinished URL: " + url);

      showLoading(false);
    }

  }

  private void showAlertError(String error){
    new AlertDialog.Builder(new ContextThemeWrapper(getActivity(), R.style.AlertDialogCustom))
        .setTitle("Error")
        .setMessage(error)
        .setPositiveButton("OK", null)
        .create()
        .show();
  }

  private void getAccessTokenFromCode(String code){
    showLoading(true);
    instaModel.getAccessToken(code)
        .subscribeOn(Schedulers.io())
        .observeOn(AndroidSchedulers.mainThread())
        .subscribe(accessToken -> {
          Log.i(TAG,"Response: " + accessToken.access_token);
          callback.onSuccess();
        }, throwable -> {
          throwable.printStackTrace();
          showAlertError(throwable.getMessage());});

    Log.e(TAG, "Code: " + code);
  }

  private void showLoading(boolean show){
    if(loading != null) {
      loading.setVisibility(show ? View.VISIBLE : View.GONE);
    }
  }


  public interface Callback{
    void onSuccess();
  }
}