Fetch a new access token in onCreate method of MainActivity when the old access token is about to expire, specifically, to expire within the next 5 minutes or is already expired to avoid refreshing the access token many times by other queries later.

app/src/main/java/ml/docilealligator/infinityforreddit/AcquireAccessToken.java

@@ -14,6 +14,7 @@ import com.android.volley.toolbox.StringRequest;
 import org.json.JSONException;
 import org.json.JSONObject;
 
+import java.util.Calendar;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -39,15 +40,16 @@ class AcquireAccessToken {
         if(mContext != null) {
             mAcquireAccessTokenListener = acquireAccessTokenListener;
             final String refreshToken = mContext.getSharedPreferences(SharedPreferencesUtils.AUTH_CODE_FILE_KEY, Context.MODE_PRIVATE).getString(SharedPreferencesUtils.REFRESH_TOKEN_KEY, "");
+            final SharedPreferences.Editor editor = mContext.getSharedPreferences(SharedPreferencesUtils.AUTH_CODE_FILE_KEY, Context.MODE_PRIVATE).edit();
             StringRequest newTokenRequest = new StringRequest(Request.Method.POST, RedditUtils.ACQUIRE_ACCESS_TOKEN_URL, new Response.Listener<String>() {
                 @Override
                 public void onResponse(String response) {
                     try {
                         JSONObject jsonObject = new JSONObject(response);
                         String newAccessToken = jsonObject.getString(RedditUtils.ACCESS_TOKEN_KEY);
-
+                        int expireIn = jsonObject.getInt(RedditUtils.EXPIRES_IN_KEY);
-                        SharedPreferences.Editor editor = mContext.getSharedPreferences(SharedPreferencesUtils.AUTH_CODE_FILE_KEY, Context.MODE_PRIVATE).edit();
                         editor.putString(SharedPreferencesUtils.ACCESS_TOKEN_KEY, newAccessToken);
+                        editor.putInt(SharedPreferencesUtils.ACCESS_TOKEN_EXPIRE_INTERVAL_KEY, expireIn);
                         editor.apply();
 
                         Log.i("access token", newAccessToken);
@@ -81,6 +83,11 @@ class AcquireAccessToken {
                 }
             };
             newTokenRequest.setTag(AcquireAccessToken.class);
+
+            long queryAccessTokenTime = Calendar.getInstance().getTimeInMillis();
+            editor.putLong(SharedPreferencesUtils.QUERY_ACCESS_TOKEN_TIME_KEY, queryAccessTokenTime);
+            editor.apply();
+
             refreshQueue.add(newTokenRequest);
         }
     }

app/src/main/java/ml/docilealligator/infinityforreddit/MainActivity.java

@@ -26,6 +26,7 @@ import com.bumptech.glide.Glide;
 import com.bumptech.glide.RequestManager;
 
 import java.util.ArrayList;
+import java.util.Calendar;
 import java.util.List;
 
 import de.hdodenhof.circleimageview.CircleImageView;
@@ -50,6 +51,7 @@ public class MainActivity extends AppCompatActivity {
     private String mBannerImageUrl;
     private String mKarma;
     private boolean mFetchUserInfoSuccess;
+    private boolean mIsInserting;
 
     private SubscribedSubredditViewModel mSubscribedSubredditViewModel;
     private SubscribedUserViewModel mSubscribedUserViewModel;
@@ -67,6 +69,25 @@ public class MainActivity extends AppCompatActivity {
         drawer.addDrawerListener(toggle);
         toggle.syncState();
 
+        Calendar now = Calendar.getInstance();
+        Calendar queryAccessTokenTime = Calendar.getInstance();
+        queryAccessTokenTime.setTimeInMillis(getSharedPreferences(SharedPreferencesUtils.AUTH_CODE_FILE_KEY, Context.MODE_PRIVATE)
+                .getLong(SharedPreferencesUtils.QUERY_ACCESS_TOKEN_TIME_KEY, 0));
+        int interval = getSharedPreferences(SharedPreferencesUtils.AUTH_CODE_FILE_KEY, Context.MODE_PRIVATE)
+                .getInt(SharedPreferencesUtils.ACCESS_TOKEN_EXPIRE_INTERVAL_KEY, 0);
+        queryAccessTokenTime.add(Calendar.SECOND, interval - 300);
+
+        if(now.after(queryAccessTokenTime)) {
+            new AcquireAccessToken(this).refreshAccessToken(Volley.newRequestQueue(this),
+                    new AcquireAccessToken.AcquireAccessTokenListener() {
+                        @Override
+                        public void onAcquireAccessTokenSuccess() {}
+
+                        @Override
+                        public void onAcquireAccessTokenFail() {}
+                    });
+        }
+
         View header = findViewById(R.id.nav_header_main_activity);
         mNameTextView = header.findViewById(R.id.name_text_view_nav_header_main);
         mKarmaTextView = header.findViewById(R.id.karma_text_view_nav_header_main);
@@ -164,14 +185,15 @@ public class MainActivity extends AppCompatActivity {
         mSubscribedSubredditViewModel.getAllSubscribedSubreddits().observe(this, new Observer<List<SubscribedSubredditData>>() {
             @Override
             public void onChanged(@Nullable final List<SubscribedSubredditData> subscribedSubredditData) {
-                // Update the cached copy of the words in the adapter.
+                if(!mIsInserting) {
-                if(subscribedSubredditData == null || subscribedSubredditData.size() == 0) {
+                    if(subscribedSubredditData == null || subscribedSubredditData.size() == 0) {
-                    subscriptionsLabelTextView.setVisibility(View.GONE);
+                        subscriptionsLabelTextView.setVisibility(View.GONE);
-                } else {
+                    } else {
-                    subscriptionsLabelTextView.setVisibility(View.VISIBLE);
+                        subscriptionsLabelTextView.setVisibility(View.VISIBLE);
-                }
+                    }
 
-                subredditadapter.setSubscribedSubreddits(subscribedSubredditData);
+                    subredditadapter.setSubscribedSubreddits(subscribedSubredditData);
+                }
             }
         });
 
@@ -181,13 +203,14 @@ public class MainActivity extends AppCompatActivity {
         mSubscribedUserViewModel.getAllSubscribedUsers().observe(this, new Observer<List<SubscribedUserData>>() {
             @Override
             public void onChanged(@Nullable final List<SubscribedUserData> subscribedUserData) {
-                // Update the cached copy of the words in the adapter.
+                if(!mIsInserting) {
-                if(subscribedUserData == null || subscribedUserData.size() == 0) {
+                    if(subscribedUserData == null || subscribedUserData.size() == 0) {
-                    followingLabelTextView.setVisibility(View.GONE);
+                        followingLabelTextView.setVisibility(View.GONE);
-                } else {
+                    } else {
-                    followingLabelTextView.setVisibility(View.VISIBLE);
+                        followingLabelTextView.setVisibility(View.VISIBLE);
+                    }
+                    userAdapter.setSubscribedUsers(subscribedUserData);
                 }
-                userAdapter.setSubscribedUsers(subscribedUserData);
             }
         });
 
@@ -197,11 +220,18 @@ public class MainActivity extends AppCompatActivity {
                     @Override
                     public void onFetchSubscribedSubredditsSuccess(ArrayList<SubscribedSubredditData> subscribedSubredditData,
                                                                    ArrayList<SubscribedUserData> subscribedUserData) {
+                        mIsInserting = true;
                         new InsertSubscribedThingsAsyncTask(
                                 SubscribedSubredditRoomDatabase.getDatabase(MainActivity.this),
                                 SubscribedUserRoomDatabase.getDatabase(MainActivity.this),
                                 subscribedSubredditData,
-                                subscribedUserData).execute();
+                                subscribedUserData,
+                                new InsertSubscribedThingsAsyncTask.InsertSubscribedThingListener() {
+                                    @Override
+                                    public void insertSuccess() {
+                                        mIsInserting = false;
+                                    }
+                                }).execute();
                     }
 
                     @Override
@@ -252,19 +282,26 @@ public class MainActivity extends AppCompatActivity {
 
     private static class InsertSubscribedThingsAsyncTask extends AsyncTask<Void, Void, Void> {
 
+        interface InsertSubscribedThingListener {
+            void insertSuccess();
+        }
+
         private final SubscribedSubredditDao mSubredditDao;
         private final SubscribedUserDao mUserDao;
         private List<SubscribedSubredditData> subscribedSubredditData;
         private List<SubscribedUserData> subscribedUserData;
+        private InsertSubscribedThingListener insertSubscribedThingListener;
 
         InsertSubscribedThingsAsyncTask(SubscribedSubredditRoomDatabase subredditDb,
                                         SubscribedUserRoomDatabase userDb,
                                         List<SubscribedSubredditData> subscribedSubredditData,
-                                        List<SubscribedUserData> subscribedUserData) {
+                                        List<SubscribedUserData> subscribedUserData,
+                                        InsertSubscribedThingListener insertSubscribedThingListener) {
             mSubredditDao = subredditDb.subscribedSubredditDao();
             mUserDao = userDb.subscribedUserDao();
             this.subscribedSubredditData = subscribedSubredditData;
             this.subscribedUserData = subscribedUserData;
+            this.insertSubscribedThingListener = insertSubscribedThingListener;
         }
 
         @Override
@@ -277,5 +314,10 @@ public class MainActivity extends AppCompatActivity {
             }
             return null;
         }
+
+        @Override
+        protected void onPostExecute(Void aVoid) {
+            insertSubscribedThingListener.insertSuccess();
+        }
     }
 }

app/src/main/java/ml/docilealligator/infinityforreddit/RedditUtils.java

@@ -34,6 +34,7 @@ class RedditUtils {
     static final String SCOPE_KEY = "scope";
     static final String SCOPE = "identity edit flair history modconfig modflair modlog modposts modwiki mysubreddits privatemessages read report save submit subscribe vote wikiedit wikiread";
     static final String ACCESS_TOKEN_KEY = "access_token";
+    static final String EXPIRES_IN_KEY = "expires_in";
 
     static final String AUTHORIZATION_KEY = "Authorization";
     static final String AUTHORIZATION_BASE = "bearer ";

app/src/main/java/ml/docilealligator/infinityforreddit/SharedPreferencesUtils.java

@@ -11,7 +11,7 @@ class SharedPreferencesUtils {
     static final String ACCESS_TOKEN_KEY = "accessToken";
     static final String REFRESH_TOKEN_KEY = "refreshToken";
     static final String QUERY_ACCESS_TOKEN_TIME_KEY = "queryAccessTokenTime";
-    static final String ACCESS_TOKEN_EXPIRE_TIME_KEY = "accessTokenExpireTime";
+    static final String ACCESS_TOKEN_EXPIRE_INTERVAL_KEY = "accessTokenExpireInterval";
     static final String MODHASH_KEY = "modhash";
     static final String USER_KEY = "user";
     static final String PROFILE_IMAGE_URL_KEY = "profileImageUrl";

app/src/main/java/ml/docilealligator/infinityforreddit/ViewSubredditDetailActivity.java

@@ -9,6 +9,8 @@ import android.support.design.widget.AppBarLayout;
 import android.support.design.widget.CollapsingToolbarLayout;
 import android.support.v7.app.AppCompatActivity;
 import android.support.v7.widget.Toolbar;
+import android.util.Log;
+import android.view.MenuItem;
 import android.widget.ImageView;
 import android.widget.TextView;
 import android.widget.Toast;
@@ -34,7 +36,11 @@ public class ViewSubredditDetailActivity extends AppCompatActivity {
         setSupportActionBar(toolbar);
 
         String id = getIntent().getExtras().getString(EXTRA_SUBREDDIT_ID);
-        final String subredditName = getIntent().getExtras().getString(EXTRA_SUBREDDIT_NAME);
+        String subredditName = getIntent().getExtras().getString(EXTRA_SUBREDDIT_NAME);
+
+        final String title = "r/" + subredditName;
+        setTitle(title);
+
         final CollapsingToolbarLayout collapsingToolbarLayout = findViewById(R.id.collapsing_toolbar_layout_view_subreddit_detail_activity);
         AppBarLayout appBarLayout = findViewById(R.id.app_bar_layout_view_subreddit_detail_activity);
         appBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
@@ -47,7 +53,8 @@ public class ViewSubredditDetailActivity extends AppCompatActivity {
                     scrollRange = appBarLayout.getTotalScrollRange();
                 }
                 if (scrollRange + verticalOffset == 0) {
-                    collapsingToolbarLayout.setTitle(subredditName);
+                    Log.i("asfasdf", "asdfasdf");
+                    collapsingToolbarLayout.setTitle(title);
                     isShow = true;
                 } else if(isShow) {
                     collapsingToolbarLayout.setTitle(" ");//carefull there should a space between double quote otherwise it wont work
@@ -114,6 +121,16 @@ public class ViewSubredditDetailActivity extends AppCompatActivity {
         });
     }
 
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        switch (item.getItemId()) {
+            case android.R.id.home:
+                finish();
+                return true;
+        }
+        return false;
+    }
+
     private static class InsertSubredditDataAsyncTask extends AsyncTask<Void, Void, Void> {
 
         private final SubredditDao mSubredditDao;

app/src/main/res/layout/activity_view_subreddit_detail.xml

@@ -82,6 +82,7 @@
                             android:layout_marginStart="16dp"
                             android:layout_marginEnd="16dp"
                             android:layout_alignParentEnd="true"
+                            android:layout_toStartOf="@id/subscriber_count_text_view_view_subreddit_detail_activity"
                             android:textColor="@android:color/black" />
 
                     </RelativeLayout>
@@ -102,9 +103,11 @@
                 android:layout_width="match_parent"
                 android:layout_height="?attr/actionBarSize"
                 app:layout_collapseMode="pin"
-                app:popupTheme="@style/AppTheme.PopupOverlay" />
+                app:popupTheme="@style/AppTheme.PopupOverlay"
+                app:navigationIcon="?attr/homeAsUpIndicator" />
 
         </android.support.design.widget.CollapsingToolbarLayout>
+
     </android.support.design.widget.AppBarLayout>
 
     <include layout="@layout/content_view_subreddit_detail" />

app/src/main/res/values/strings.xml

@@ -19,7 +19,6 @@
     <string name="profile">Profile</string>
     <string name="following">Following</string>
     <string name="subscriptions">Subscriptions</string>
-    <string name="title_activity_view_subreddit_detail">ViewSubredditDetailActivity</string>
     <string name="subscribers_number_detail">Subscribers: %1$d</string>
     <string name="online_subscribers_number_detail">Online: %1$d</string>
     <string name="large_text">