Use cached conversation list to display quickly an old version of it

app/src/main/java/org/communiquons/android/comunic/client/data/helpers/ConversationsListDbHelper.java

@@ -18,7 +18,25 @@ import java.util.ArrayList;
  * Created by pierre on 12/13/17.
  */
 
-public class ConversationsListDbHelper {
+class ConversationsListDbHelper {
+
+    /**
+     * Debug tag
+     */
+    private static final String TAG = ConversationsListDbHelper.class.getSimpleName();
+
+    /**
+     * The list of all the columns of the database
+     */
+    private static final String[] mAllColumns = {
+            ConversationsListSchema.COLUMN_NAME_CONVERSATION_ID,
+            ConversationsListSchema.COLUMN_NAME_CONVERSATION_ID_OWNER,
+            ConversationsListSchema.COLUMN_NAME_CONVERSATION_LAST_ACTIVE,
+            ConversationsListSchema.COLUMN_NAME_CONVERSATION_NAME,
+            ConversationsListSchema.COLUMN_NAME_CONVERSATION_FOLLOWING,
+            ConversationsListSchema.COLUMN_NAME_CONVERSATION_SAW_LAST_MESSAGES,
+            ConversationsListSchema.COLUMN_NAME_CONVERSATION_MEMBERS,
+    };
 
     /**
      * Pointer on the database
@@ -35,11 +53,40 @@ public class ConversationsListDbHelper {
      *
      * @param databaseHelper Object pointing on database helper
      */
-    public ConversationsListDbHelper(@NonNull DatabaseHelper databaseHelper){
+    ConversationsListDbHelper(@NonNull DatabaseHelper databaseHelper){
         this.databaseHelper = databaseHelper;
     }
 
 
+    /**
+     * Get the list of conversation stored in the database
+     *
+     * @return The list of conversations
+     */
+    ArrayList<ConversationInfo> getList(){
+
+        SQLiteDatabase db = databaseHelper.getReadableDatabase();
+
+        Cursor c = db.query(TABLE_NAME, mAllColumns, null, null, null,
+                null,
+                ConversationsListSchema.COLUMN_NAME_CONVERSATION_LAST_ACTIVE + " DESC");
+
+        ArrayList<ConversationInfo> list = new ArrayList<>();
+        if(c.getCount() < 1)
+            return list;
+
+        c.moveToFirst();
+
+        while(!c.isAfterLast()){
+            list.add(getConvObj(c));
+            c.moveToNext();
+        }
+
+        c.close();
+
+        return list;
+    }
+
     /**
      * Update the list of conversations currently installed in the system with a new list
      *
@@ -60,7 +107,6 @@ public class ConversationsListDbHelper {
                 success = false;
         }
 
-        //db.close();
 
         return success;
     }
@@ -77,35 +123,25 @@ public class ConversationsListDbHelper {
 
         //Prepare database request
         String table = ConversationsListSchema.TABLE_NAME;
-        String[] columns = {
-                ConversationsListSchema.COLUMN_NAME_CONVERSATION_ID,
-                ConversationsListSchema.COLUMN_NAME_CONVERSATION_ID_OWNER,
-                ConversationsListSchema.COLUMN_NAME_CONVERSATION_LAST_ACTIVE,
-                ConversationsListSchema.COLUMN_NAME_CONVERSATION_NAME,
-                ConversationsListSchema.COLUMN_NAME_CONVERSATION_FOLLOWING,
-                ConversationsListSchema.COLUMN_NAME_CONVERSATION_SAW_LAST_MESSAGES,
-                ConversationsListSchema.COLUMN_NAME_CONVERSATION_MEMBERS,
-        };
         String selection = ConversationsListSchema.COLUMN_NAME_CONVERSATION_ID + " = ?";
         String[] selectionArgs = {""+convID};
 
         //Perform database request
-        Cursor c = db.query(table, columns, selection, selectionArgs, null, null, null);
+        Cursor c = db.query(table, mAllColumns, selection, selectionArgs, null, null, null);
 
-        ConversationInfo infos = null;
+        ConversationInfo info = null;
 
         //Check for result
         if(c.getCount() != 0){
             c.moveToFirst();
 
             //Parse result
-            infos = getConvObj(c);
+            info = getConvObj(c);
         }
 
         c.close();
-        //db.close();
 
-        return infos;
+        return info;
 
     }
 
@@ -135,7 +171,6 @@ public class ConversationsListDbHelper {
         //Prepare the request
         db.delete(TABLE_NAME, null, null);
 
-        //db.close();
     }
 
     /**

app/src/main/java/org/communiquons/android/comunic/client/data/helpers/ConversationsListHelper.java

@@ -85,6 +85,15 @@ public class ConversationsListHelper extends BaseHelper {
         return list;
     }
 
+    /**
+     * Get the cached version of the list of conversation
+     *
+     * @return The cached list of conversations
+     */
+    public ArrayList<ConversationInfo> getCachedList(){
+        return convDBHelper.getList();
+    }
+
     /**
      * Get information about a conversation
      *

app/src/main/java/org/communiquons/android/comunic/client/ui/asynctasks/GetConversationsListTask.java

@@ -12,17 +12,24 @@ import java.util.ArrayList;
  *
  * @author Pierre HUBERT
  */
-public class GetConversationsListTask extends SafeAsyncTask<Void, Void, ArrayList<ConversationInfo>> {
+public class GetConversationsListTask extends SafeAsyncTask<Boolean, Void, ArrayList<ConversationInfo>> {
 
     public GetConversationsListTask(Context context) {
         super(context);
     }
 
     @Override
-    protected ArrayList<ConversationInfo> doInBackground(Void... voids) {
+    protected ArrayList<ConversationInfo> doInBackground(Boolean... booleans) {
         ConversationsListHelper conversationsListHelper = new ConversationsListHelper(getContext());
 
-        ArrayList<ConversationInfo> list = conversationsListHelper.getOnline();
+        boolean getOnline = booleans[0];
+        ArrayList<ConversationInfo> list;
+
+
+        if(getOnline)
+            list = conversationsListHelper.getOnline();
+        else
+            list = conversationsListHelper.getCachedList();
 
         if(list == null || !conversationsListHelper.getConversationsDisplayName(list))
             return null;

app/src/main/java/org/communiquons/android/comunic/client/ui/fragments/ConversationsListFragment.java

@@ -30,6 +30,7 @@ import org.communiquons.android.comunic.client.ui.listeners.openConversationList
 import org.communiquons.android.comunic.client.ui.listeners.updateConversationListener;
 
 import java.util.ArrayList;
+import java.util.Objects;
 
 /**
  * Conversation list fragment
@@ -92,6 +93,11 @@ public class ConversationsListFragment extends AbstractFragment implements Adapt
      */
     private ProgressBar mProgressBar;
 
+    /**
+     * Specify whether we got the first version of the list of conversation
+     */
+    private boolean mGotFirstList = false;
+
     @Nullable
     @Override
     public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
@@ -106,7 +112,7 @@ public class ConversationsListFragment extends AbstractFragment implements Adapt
         DatabaseHelper dbHelper = DatabaseHelper.getInstance(getActivity());
 
         //Instantiate the user information helper
-        userHelper = new GetUsersHelper(getActivity(), dbHelper);
+        userHelper = new GetUsersHelper(Objects.requireNonNull(getActivity()), dbHelper);
 
         //Create the conversation list helper
         conversationsListHelper = new ConversationsListHelper(getActivity(), dbHelper);
@@ -122,7 +128,7 @@ public class ConversationsListFragment extends AbstractFragment implements Adapt
         mNoConversationNotice.setVisibility(View.GONE);
 
         //Refresh conversations list
-        refresh_conversations_list();
+        refresh_conversations_list(false);
 
         //Set the open and update conversation listener
         try {
@@ -143,14 +149,14 @@ public class ConversationsListFragment extends AbstractFragment implements Adapt
         super.onResume();
 
         //Update activity title
-        getActivity().setTitle(R.string.fragment_conversationslist_title);
+        Objects.requireNonNull(getActivity()).setTitle(R.string.fragment_conversationslist_title);
         MainActivity.SetNavbarSelectedOption(getActivity(), R.id.action_conversations);
     }
 
     /**
      * Refresh the list of conversations
      */
-    private void refresh_conversations_list(){
+    private void refresh_conversations_list(boolean online){
 
         //Display loading wheel
         mProgressBar.setVisibility(View.VISIBLE);
@@ -158,7 +164,7 @@ public class ConversationsListFragment extends AbstractFragment implements Adapt
         //Get the list of conversations
         GetConversationsListTask getConversationsListTask = new GetConversationsListTask(getActivity());
         getConversationsListTask.setOnPostExecuteListener(this::display_conversations_list);
-        getConversationsListTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
+        getConversationsListTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, online);
         getTasksManager().addTask(getConversationsListTask);
     }
 
@@ -167,13 +173,20 @@ public class ConversationsListFragment extends AbstractFragment implements Adapt
      *
      * @param list The list to display
      */
-    public void display_conversations_list(ArrayList<ConversationInfo> list){
+    public void display_conversations_list(@Nullable ArrayList<ConversationInfo> list){
+
+        display_progress_bar(false);
+
+        //Check if we were fetching the local list of conversation
+        if(!mGotFirstList) {
+            mGotFirstList = true;
+            refresh_conversations_list(true);
+        }
 
         //Check if we got a list
         if(list == null) {
             Toast.makeText(getActivity(), R.string.fragment_conversationslist_err_get_list,
                     Toast.LENGTH_LONG).show();
-            display_progress_bar(false);
             return;
         }
 
@@ -189,17 +202,11 @@ public class ConversationsListFragment extends AbstractFragment implements Adapt
         //Add click listener
         conversationsListView.setOnItemClickListener(this);
 
-        conversationsListView.setOnCreateContextMenuListener(new View.OnCreateContextMenuListener() {
+        conversationsListView.setOnCreateContextMenuListener((menu, v, menuInfo) -> {
-            @Override
+            MenuInflater inflater = Objects.requireNonNull(getActivity()).getMenuInflater();
-            public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
-                MenuInflater inflater = getActivity().getMenuInflater();
             inflater.inflate(R.menu.menu_fragment_conversationslist_item, menu);
-            }
         });
 
-        //Remove progress bar
-        display_progress_bar(false);
-
         //Update the visibility of the no conversation notice
         updateNoConversationNotice();
     }
@@ -272,12 +279,8 @@ public class ConversationsListFragment extends AbstractFragment implements Adapt
                 .setMessage(R.string.popup_deleteconversation_messsage)
                 .setNegativeButton(R.string.popup_deleteconversation_cancel, null)
 
-                .setPositiveButton(R.string.popup_deleteconversation_confirm, new DialogInterface.OnClickListener() {
+                .setPositiveButton(R.string.popup_deleteconversation_confirm,
-                    @Override
+                        (dialog, which) -> delete_conversation(convID))
-                    public void onClick(DialogInterface dialog, int which) {
-                        delete_conversation(convID);
-                    }
-                })
 
                 .show();
 
@@ -303,7 +306,7 @@ public class ConversationsListFragment extends AbstractFragment implements Adapt
                 if(getActivity() == null)
                     return;
 
-                refresh_conversations_list();
+                refresh_conversations_list(true);
 
                 //Display a toast if an error occurred
                 if(!result)