Twitter integration in an Android App

Prerequisites:

1. Consumer Key
2. Consumer key secret
3. Signpost-core and signpost-commonshttp libs

Approach:

launch the twitter authentication in a webview and present the login page to user in it.

When user enters the credentials, validate them and proceed.

Activity TwitterConnectWebActivity:

** You can copy the following whole activity in your code, as its a standalone code

public class TwitterConnectWebActivity extends Activity {

    private static final String TAG = "TwitterConnectWebActivity";

    private static String TWITTER_IMAGE_URL = "http://api.twitter.com/1/users/profile_image/@user.json";

    private static final int LOADING_DIALOG_ID = 0;

    protected final String CALLBACKURL = "OauthTwitter://taylorswiftapp";

    protected static CommonsHttpOAuthConsumer twitterHttpOauthConsumer;

    protected static OAuthProvider twitterHttpOauthprovider;

    protected int TWITTER_LOGIN_REQUEST_CODE = 1;

    protected int TWITTER_LOGOUT_REQUEST_CODE = 2;

    AccessToken twitterAuthToken;

    Context context;

    WebView webview;

    ProgressBar progressBar;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.tw_connect_web_activity);

        context = this;

        webview = (WebView) findViewById(R.id.webview);

        progressBar = (ProgressBar) findViewById(R.id.progress_bar);

        new RequestTokenSecretUrlTask().execute();

    }

    private class RequestTokenSecretUrlTask extends

            AsyncTask<Void, Void, String> {

        @Override

        protected void onPreExecute() {

            showDialog(LOADING_DIALOG_ID);

        }

        @Override

        protected String doInBackground(Void... params) {

            try {

                twitterHttpOauthConsumer = new CommonsHttpOAuthConsumer( "YOUR_CONSUMER_KEY",

"YOUR_CONSUMER_SECRET");

                twitterHttpOauthprovider = new DefaultOAuthProvider(

                        "https://api.twitter.com/oauth/request_token",

                        "https://api.twitter.com/oauth/access_token",

                        "https://api.twitter.com/oauth/authorize");

                String authUrl = twitterHttpOauthprovider.retrieveRequestToken(

                        twitterHttpOauthConsumer, CALLBACKURL);

                Log.e(TAG, "Load URL : " + authUrl);

                return authUrl;

            } catch (Exception e) {

                e.printStackTrace();

            }

            return null;

        }

        @Override

        protected void onPostExecute(String authUrl) {

            dismissDialog(LOADING_DIALOG_ID);

            webview.setWebViewClient(new TwitterWebViewClient());

            webview.getSettings().setPluginsEnabled(true);

            webview.getSettings().setJavaScriptEnabled(true);

            webview.getSettings().setLayoutAlgorithm(

                    WebSettings.LayoutAlgorithm.NARROW_COLUMNS);

            webview.loadUrl(authUrl);

        }

    }

    private class TwitterWebViewClient extends WebViewClient {

        @Override

        public boolean shouldOverrideUrlLoading(WebView view, String url) {

            Log.e(TAG, "shouldOverrideUrlLoading() -> url:" + url);

            progressBar.setVisibility(View.VISIBLE);

            Uri uri = Uri.parse(url);

            if (uri != null && uri.toString().startsWith(CALLBACKURL)) {

                String verifier = uri

                        .getQueryParameter(oauth.signpost.OAuth.OAUTH_VERIFIER);

                try {

                    twitterHttpOauthprovider.retrieveAccessToken(

                            twitterHttpOauthConsumer, verifier);

                    twitterAuthToken = new AccessToken(twitterHttpOauthConsumer

                            .getToken(), twitterHttpOauthConsumer

                            .getTokenSecret());

                    ConfigurationBuilder cb = new ConfigurationBuilder();

                    cb.setDebugEnabled(true).setOAuthConsumerKey(

                            twitterHttpOauthConsumer.getConsumerKey())

                            .setOAuthConsumerSecret(

                                    twitterHttpOauthConsumer

                                            .getConsumerSecret())

                            .setOAuthAccessToken(twitterAuthToken.getToken())

                            .setOAuthAccessTokenSecret(

                                    twitterAuthToken.getTokenSecret());

                    TwitterFactory tf = new TwitterFactory(cb.build());

                    Twitter twitter = tf.getInstance();

                    // if authentication is done,set result to ok finish this

                    // activity

                    Intent intent = new Intent();

                    intent

                            .putExtra("access_token", twitterAuthToken

                                    .getToken());

                    intent.putExtra("access_secret", twitterAuthToken

                            .getTokenSecret());

                    String name = twitter.getScreenName();

                    intent.putExtra("twitter_screen_name", name);

                    intent.putExtra("twitter_uid", "" + twitter.getId());

                    intent

                            .putExtra("twitter_image_url", ""

                                    + twitter.getProfileImage(name,

                                            ProfileImage.BIGGER));

                    setResult(RESULT_OK, intent);

                    finish();

                } catch (Exception e) {

                    e.printStackTrace();

                }

                return true;

            } else {

                Log.e(TAG, " ::2222:: Twitter URl --- " + url);

                view.loadUrl(url);

                return true;

            }

        }

        @Override

        public void onPageFinished(WebView view, String url) {

            progressBar.setVisibility(View.INVISIBLE);

        }

    }

    @Override

    protected Dialog onCreateDialog(int id) {

        switch (id) {

        case LOADING_DIALOG_ID:

            ProgressDialog dialog = new ProgressDialog(this);

            dialog.setMessage("Loading...");

            dialog.setOnCancelListener(new DialogInterface.OnCancelListener() {

                public void onCancel(DialogInterface arg0) {

                    finish();

                }

            });

            return dialog;

        default:

            return super.onCreateDialog(id);

        }

    }

}

NOW, from the point where you wanna start this twitter stuff, just call:

startActivity(new Intent(this, TwitterConnectWebActivity.class));

In manifest add this permission:

<uses-permission

        android:name="android.permission.INTERNET" />

You are done.

Android: Broadcast Receivers made simple

Lets say you have a requirement:
App starts with Activities A,B and C and then Activity D is started.
A,B and C are the activities for just one time like Terms and Conditions etc, that user should not be able to see them once he has successfully navigated from A->B->C and then to D.

Lets solve this basic problem using BroadcastReceivers:

In your Activity A:

Activity A{

public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

...

IntentFilter myFilter = new IntentFilter("finish"); // "finish" can be any string you wanna provide
registerReceiver(myReceiver, myFilter);


}


BroadcastReceiver myReceiver = new BroadcastReceiver() {

@Override
public void onReceive(Context context, Intent intent) {
Log.d("ActivityA", "finishing A");
finish();
}
};

@Override
protected void onDestroy() {
unregisterReceiver(myReceiver);
super.onDestroy();
}


}

Similarly register for this broadcast receiver in all other activities you wanna finish at a single action.

Now in Activity D,

you just need to call
sendBroadcast(new Intent("finish"));


at the point where you want that all the activities who have registered for your receiver must get finished.

P.S. Its mandatory to unregister the receiver at some point else there can be a possible exception.