An OAuth test for the JRAW library on Android

MainActivity.java

import net.dean.jraw.RedditClient;
import net.dean.jraw.http.LoggingMode;
import net.dean.jraw.http.NetworkException;
import net.dean.jraw.http.UserAgent;
import net.dean.jraw.http.oauth.Credentials;
import net.dean.jraw.http.oauth.OAuthData;
import net.dean.jraw.http.oauth.OAuthException;
import net.dean.jraw.http.oauth.OAuthHelper;

import android.app.Activity;
import android.graphics.Bitmap;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.webkit.CookieManager;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ProgressBar;
import android.widget.TextView;


public class MainActivity extends Activity {

    private static final String LOG_TAG = MainActivity.class.getSimpleName();

    private static final String CLIENT_ID = "THE_APP_PUBLIC_ID";

    private static final String REDIRECT_URL = "https://example.com/auth/";

    private static RedditClient mRedditClient;

    private TextView mTextView;

    private String mRefreshToken = "PUT_TOKEN_HERE";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        Log.v(LOG_TAG, "onCreate()");
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        final Activity activity = this;
        final ProgressBar progressBar = (ProgressBar) findViewById(R.id.progress_bar);
        WebView webView = (WebView) findViewById(R.id.web_view);
        mTextView = (TextView) findViewById(R.id.text_view);

        mRedditClient = new RedditClient(UserAgent.of("JrawTest 0.1"));
        mRedditClient.setLoggingMode(LoggingMode.ALWAYS);
        final OAuthHelper oAuthHelper = mRedditClient.getOAuthHelper();
        // This is Android, so our OAuth app should be an installed app.
        final Credentials credentials = Credentials.installedApp(CLIENT_ID, REDIRECT_URL);

        // Try to refresh the token
        if(!mRefreshToken.isEmpty()) {
            new TokenRefreshTask().execute();
            return;
        }

        // If this is true, then you will be able to refresh to access token
        boolean permanent = true;

        // OAuth2 scopes to request. See https://www.reddit.com/dev/api/oauth for a full list
        String[] scopes = {"identity", "read", "vote", "save", "mysubreddits"};

        String authorizationUrl = oAuthHelper.getAuthorizationUrl(credentials, permanent, scopes)
                .toExternalForm();
        authorizationUrl = authorizationUrl.replace("www.", "i.");
        Log.v(LOG_TAG, "Auth URL: " + authorizationUrl);

        // Load the authorization URL into the browser
        CookieManager cookieManager = CookieManager.getInstance();
        cookieManager.removeAllCookie();

        webView.loadUrl(authorizationUrl);
        webView.setWebChromeClient(new WebChromeClient() {
            @Override
            public void onProgressChanged(WebView view, int newProgress) {
//                activity.setProgress(newProgress * 1000);
                progressBar.setProgress(newProgress);
            }
        });

        webView.setWebViewClient(new WebViewClient() {
            @Override
            public void onPageStarted(WebView view, String url, Bitmap favicon) {
                if (url.contains("code=")) {
                    Log.v(LOG_TAG, "WebView URL: " + url);
                    // We've detected the redirect URL
                    new UserChallengeTask(oAuthHelper, credentials).execute(url);
                }
            }
        });
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        Log.v(LOG_TAG, "onCreateOptionsMenu()");
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        Log.v(LOG_TAG, "onOptionsItemSelected()");
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    private void performRedditLogin() {

    }

    private final class TokenRefreshTask extends AsyncTask<String, Void, OAuthData> {

        @Override
        protected OAuthData doInBackground(String... params) {

            if (!mRefreshToken.isEmpty()) {
                final Credentials credentials = Credentials.installedApp(CLIENT_ID, REDIRECT_URL);
                OAuthHelper oAuthHelper = mRedditClient.getOAuthHelper();
                oAuthHelper.setRefreshToken(mRefreshToken);
                try {
                    OAuthData finalData = oAuthHelper.refreshToken(credentials);
                    mRedditClient.authenticate(finalData);
                    if (mRedditClient.isAuthenticated()) {
                        Log.v(LOG_TAG, "Authenticated");
                    }
                } catch (OAuthException e) {
                    e.printStackTrace();
                }
            }
            return null;
        }
    }

    private final class UserChallengeTask extends AsyncTask<String, Void, OAuthData> {

        private OAuthHelper mOAuthHelper;

        private Credentials mCredentials;

        public UserChallengeTask(OAuthHelper oAuthHelper, Credentials credentials) {
            Log.v(LOG_TAG, "UserChallengeTask()");
            mOAuthHelper = oAuthHelper;
            mCredentials = credentials;
        }

        @Override
        protected OAuthData doInBackground(String... params) {
            Log.v(LOG_TAG, "doInBackground()");
            Log.v(LOG_TAG, "params[0]: " + params[0]);
            try {
                return mOAuthHelper.onUserChallenge(params[0], mCredentials);
            } catch (IllegalStateException | NetworkException | OAuthException e) {
                // Handle me gracefully
                Log.e(LOG_TAG, "OAuth failed");
                Log.e(LOG_TAG, e.getMessage());
            }
            return null;
        }

        @Override
        protected void onPostExecute(OAuthData oAuthData) {
            Log.v(LOG_TAG, "onPostExecute()");
            if (oAuthData != null) {
                mRedditClient.authenticate(oAuthData);
                Log.v(LOG_TAG, "Reddit client authentication: " + mRedditClient.isAuthenticated());
                mTextView.setText("Logged in");
                //TODO: Save refresh token:
                String refreshToken = mRedditClient.getOAuthData().getRefreshToken();
                Log.v(LOG_TAG, "Refresh Token: " + refreshToken);
            } else {
                Log.e(LOG_TAG, "Passed in OAuthData was null");
            }
        }
    }
}