问OAuth:缺少参数response_type

EN

{"error":"invalid_request","error_description":"Missing required parameter: response_type"}

public class OAuthActivity extends Activity {

public static String OAUTH_URL = "https://api.misfitwearables.com/auth/dialog/authorize";
public static String OAUTH_ACCESS_TOKEN_URL = "https://api.misfitwearables.com/auth/tokens/exchange";

public static String CLIENT_ID = "Here's a client ID";
public static String CLIENT_SECRET = "and the secret, that obviously stays hidden.";
public static String CALLBACK_URL = "http://localhost";

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

    String url = OAUTH_URL + "?client_id=" + CLIENT_ID;

    WebView webview = (WebView)findViewById(R.id.webview);
    webview.getSettings().setJavaScriptEnabled(true);
    final SharedPreferences prefs = this.getSharedPreferences(
            "com.iss_fitness.myapplication", Context.MODE_PRIVATE);
    webview.setWebViewClient(new WebViewClient() {
        public void onPageStarted(WebView view, String URL, Bitmap favicon) {
            String accessTokenFragment = "access_token=";
            String accessCodeFragment = "code=";

            // We hijack the GET request to extract the OAuth parameters

            if (url.contains(accessTokenFragment)) {
                // the GET request contains directly the token
                String accessToken = url.substring(url.indexOf(accessTokenFragment));
                prefs.edit().putString("Token", accessToken);

            } else if(url.contains(accessCodeFragment)) {
                // the GET request contains an authorization code
                String accessCode = url.substring(url.indexOf(accessCodeFragment));
                prefs.edit().putString("Code", accessCode);


                String query = "&client_id=" + CLIENT_ID + "&client_secret=" + CLIENT_SECRET + "&code=" + accessCode;
                view.postUrl(OAUTH_ACCESS_TOKEN_URL, query.getBytes());
            }

        }



    });
    webview.loadUrl(url);


}