Preparation for upcoming alarm functionality

lib/obp60task/PageVoltage.cpp

@@ -100,7 +100,7 @@ public:
         getdisplay().fillRect(x + 16, y + 11, 6, 3, color);
     }
 
-    virtual void displayPage(PageData &pageData){
+    int displayPage(PageData &pageData){
         GwConfigHandler *config = commonData->config;
         GwLog *logger = commonData->logger;
         
@@ -383,8 +383,7 @@ public:
 
         }
 
-        // Update display
-        getdisplay().nextPage();    // Partial update (fast)
+        return PAGE_UPDATE;
     };
 };