doc

README.md

@@ -104,6 +104,39 @@ then you can load api key from json file.
 CocoaTweet::Authentication::Key key = CocoaTweet::Authentication::Key::fromJsonFile("api_key.json");
 ```
 
+### 3. Authenticate with API call
+※ consumer key, consumer secret are needed. in this case, get access token with api call.
+```
+CocoaTweet::API::API api(key);
+
+auto oAuthToken = api.oauth1().requestToken("oob");
+const auto signInUrl = api.oauth1().authorize(oAuthToken);
+std::cout << "signin : " << signInUrl << std::endl;
+std::string pin = "";
+std::cout << "pincode : ";
+std::cin >> pin;
+
+const auto validOAuthToken = api.oauth1().accessToken(oAuthToken, pin);
+key.accessToken(validOAuthToken.oauthToken());
+key.accessTokenSecret(validOAuthToken.oauthTokenSecret());
+api.swapKey(key);
+```
+
+
+### 4. Get BearerToken with AIP call
+if you want to call Twitter API using Bearer Token; OAuth2, you can do.
+```
+CocoaTweet::API::API api(key);
+auto bearerToken = api.oauth2().token();
+key.bearerToken(bearerToken);
+key.authType(CocoaTweet::Authentication::Key::AUTH_TYPE::OAUTH2);
+api.swapKey(key);
+```
+
+After call it, always use Bearer Token to access API which kinds of GET method.  
+no affect to POST method.  
+then, if you use this, and ONLY use kind of GET API, you DO NOT need acess token.
+
 ## Generate API object
 generating API object with Key.  
 this object is API entry point.  
@@ -115,15 +148,6 @@ CocoaTweet::API::API api(key);
 
 ```
 
-### NOTE
-if you want to call Twitter API using Bearer Token; OAuth2, you can do.
-```
-api.generateBearerToken();
-```
-After call it, always use Bearer Token to access API which kinds of GET method.  
-no affect to POST method.  
-then, if you use this, and ONLY use kind of GET API, you DO NOT need acess token.
-
 
 ## Use API
 ```