Added menu item to show/hide child folders in the nav menu

app/src/main/java/eu/faircode/email/AdapterFolder.java

@@ -662,7 +662,9 @@ public class AdapterFolder extends RecyclerView.Adapter<AdapterFolder.ViewHolder
                 submenu.add(Menu.FIRST, R.string.title_synchronize_batch_disable, 3, R.string.title_synchronize_batch_disable);
                 submenu.add(Menu.FIRST, R.string.title_notify_batch_enable, 4, R.string.title_notify_batch_enable);
                 submenu.add(Menu.FIRST, R.string.title_notify_batch_disable, 5, R.string.title_notify_batch_disable);
-                submenu.add(Menu.FIRST, R.string.title_synchronize_more, 6, R.string.title_synchronize_more);
+                submenu.add(Menu.FIRST, R.string.title_navigation_folder, 6, R.string.title_navigation_folder);
+                submenu.add(Menu.FIRST, R.string.title_navigation_folder_hide, 7, R.string.title_navigation_folder_hide);
+                submenu.add(Menu.FIRST, R.string.title_synchronize_more, 8, R.string.title_synchronize_more);
             }
 
             if (folder.account != null && folder.accountProtocol == EntityAccount.TYPE_IMAP)
@@ -695,6 +697,12 @@ public class AdapterFolder extends RecyclerView.Adapter<AdapterFolder.ViewHolder
                         } else if (itemId == R.string.title_notify_batch_disable) {
                             onActionEnableNotify(false);
                             return true;
+                        } else if (itemId == R.string.title_navigation_folder) {
+                            onActionEnableNavigationMenu(true);
+                            return true;
+                        } else if (itemId == R.string.title_navigation_folder_hide) {
+                            onActionEnableNavigationMenu(false);
+                            return true;
                         } else if (itemId == R.string.title_synchronize_more) {
                             onActionSyncMore(true);
                             return true;
@@ -921,6 +929,42 @@ public class AdapterFolder extends RecyclerView.Adapter<AdapterFolder.ViewHolder
                     }.execute(context, owner, args, "enable");
                 }
 
+                private void onActionEnableNavigationMenu(boolean enabled) {
+                    Bundle args = new Bundle();
+                    args.putLong("id", folder.id);
+                    args.putBoolean("enabled", enabled);
+
+                    new SimpleTask<Void>() {
+                        @Override
+                        protected Void onExecute(Context context, Bundle args) throws Throwable {
+                            long id = args.getLong("id");
+                            boolean enabled = args.getBoolean("enabled");
+
+                            DB db = DB.getInstance(context);
+                            try {
+                                db.beginTransaction();
+                                List<EntityFolder> childs = db.folder().getChildFolders(id);
+                                if (childs == null)
+                                    return null;
+
+                                for (EntityFolder child : childs)
+                                    db.folder().setFolderNavigation(child.id, enabled);
+
+                                db.setTransactionSuccessful();
+                            } finally {
+                                db.endTransaction();
+                            }
+
+                            return null;
+                        }
+
+                        @Override
+                        protected void onException(Bundle args, Throwable ex) {
+                            Log.unexpectedError(parentFragment.getParentFragmentManager(), ex);
+                        }
+                    }.execute(context, owner, args, "enable");
+                }
+
                 private void onActionSyncMore(boolean children) {
                     Bundle args = new Bundle();
                     args.putLong("folder", folder.id);

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

@@ -1146,6 +1146,7 @@
     <string name="title_hide_seen_folder_hint">Only in the folder list shown on the start screen</string>
     <string name="title_unified_folder">Show in unified inbox</string>
     <string name="title_navigation_folder">Show in navigation menu</string>
+    <string name="title_navigation_folder_hide">Hide in navigation menu</string>
     <string name="title_synchronize_folder">Synchronize (receive messages)</string>
     <string name="title_poll_folder">Check periodically instead of continuous synchronize</string>
     <string name="title_poll_folder_remark">Most email servers allow push messages for a handful of folders only!</string>