From 5a420c381abb1cc926481d33c88206e01c239292 Mon Sep 17 00:00:00 2001
From: KlausMu <kmusch@gmail.com>
Date: Sun, 21 Apr 2024 17:53:28 +0200
Subject: [PATCH] reorganized deletion and creation of tabs

---
 .../ESP32/preferencesStorage_hal_esp32.cpp    |  39 +-
 .../ESP32/preferencesStorage_hal_esp32.h      |  10 +-
 .../preferencesStorage_hal_windows_linux.cpp  |  57 ++-
 .../preferencesStorage_hal_windows_linux.h    |  10 +-
 .../src/applicationInternal/gui/guiBase.cpp   |  55 ++-
 .../src/applicationInternal/gui/guiBase.h     |   5 +-
 .../gui/guiMemoryOptimizer.cpp                | 440 ++++++++++--------
 .../gui/guiMemoryOptimizer.h                  |  26 +-
 .../hardware/hardwarePresenter.cpp            |  22 +-
 .../hardware/hardwarePresenter.h              |  10 +-
 Platformio/src/applicationInternal/keys.cpp   |  17 +-
 .../scenes/sceneHandler.cpp                   |  48 +-
 .../applicationInternal/scenes/sceneHandler.h |   2 +-
 .../scenes/sceneRegistry.cpp                  |  60 +--
 .../scenes/sceneRegistry.h                    |   4 +-
 Platformio/src/guis/gui_numpad.cpp            |   4 +-
 Platformio/src/main.cpp                       |   2 +-
 17 files changed, 469 insertions(+), 342 deletions(-)

diff --git a/Platformio/hardware/ESP32/preferencesStorage_hal_esp32.cpp b/Platformio/hardware/ESP32/preferencesStorage_hal_esp32.cpp
index 6666e4b..2577482 100644
--- a/Platformio/hardware/ESP32/preferencesStorage_hal_esp32.cpp
+++ b/Platformio/hardware/ESP32/preferencesStorage_hal_esp32.cpp
@@ -4,8 +4,9 @@
 
 Preferences preferences;
 
-std::string currentScene;
-std::string currentGUIname;
+std::string activeScene;
+std::string activeGUIname;
+int activeGUIlist;
 
 void init_preferences_HAL(void) {
   // Restore settings from internal flash memory
@@ -17,10 +18,11 @@ void init_preferences_HAL(void) {
     // from tft.h
     set_backlightBrightness_HAL(preferences.getUChar("blBrightness"));
     // from here
-    currentScene = std::string(preferences.getString("currentScene").c_str());
-    currentGUIname = std::string(preferences.getString("currentGUIname").c_str());
+    activeScene = std::string(preferences.getString("currentScene").c_str());
+    activeGUIname = std::string(preferences.getString("currentGUIname").c_str());
+    activeGUIlist =(preferences.getInt("currentGUIlist"));
 
-    // Serial.printf("Preferences restored: brightness %d, GUI %s, scene %s\r\n", get_backlightBrightness_HAL(), get_currentGUIname().c_str(), get_currentScene().c_str());
+    // Serial.printf("Preferences restored: brightness %d, GUI %s, scene %s\r\n", get_backlightBrightness_HAL(), get_activeGUIname().c_str(), get_activeScene().c_str());
   } else {
     // Serial.printf("No preferences to restore\r\n");
   }
@@ -35,23 +37,30 @@ void save_preferences_HAL(void) {
   preferences.putUInt("slpTimeout", get_sleepTimeout_HAL());
   preferences.putUChar("blBrightness", get_backlightBrightness_HAL());
   // from here
-  preferences.putString("currentScene", currentScene.c_str());
-  preferences.putString("currentGUIname", currentGUIname.c_str());
+  preferences.putString("currentScene", activeScene.c_str());
+  preferences.putString("currentGUIname", activeGUIname.c_str());
+  preferences.putInt("currentGUIlist", activeGUIlist);
   if (!preferences.getBool("alreadySetUp")) {
     preferences.putBool("alreadySetUp", true);
   }
   preferences.end();
 }
 
-std::string get_currentScene_HAL() {
-  return currentScene;
+std::string get_activeScene_HAL() {
+  return activeScene;
 }
-void set_currentScene_HAL(std::string aCurrentScene) {
-  currentScene = aCurrentScene;
+void set_activeScene_HAL(std::string anActiveScene) {
+  activeScene = anActiveScene;
 }
-std::string get_currentGUIname_HAL(){
-  return currentGUIname;
+std::string get_activeGUIname_HAL(){
+  return activeGUIname;
 }
-void set_currentGUIname_HAL(std::string aCurrentGUIname) {
-  currentGUIname = aCurrentGUIname;
+void set_activeGUIname_HAL(std::string anActiveGUIname) {
+  activeGUIname = anActiveGUIname;
+}
+int get_activeGUIlist_HAL() {
+  return activeGUIlist;
+}
+void set_activeGUIlist_HAL(int anActiveGUIlist) {
+  activeGUIlist = anActiveGUIlist;
 }
diff --git a/Platformio/hardware/ESP32/preferencesStorage_hal_esp32.h b/Platformio/hardware/ESP32/preferencesStorage_hal_esp32.h
index f94f0f4..9f4d98e 100644
--- a/Platformio/hardware/ESP32/preferencesStorage_hal_esp32.h
+++ b/Platformio/hardware/ESP32/preferencesStorage_hal_esp32.h
@@ -5,7 +5,9 @@
 void init_preferences_HAL(void);
 void save_preferences_HAL(void);
 
-std::string get_currentScene_HAL();
-void set_currentScene_HAL(std::string aCurrentScene);
-std::string get_currentGUIname_HAL();
-void set_currentGUIname_HAL(std::string aCurrentGUIname);
+std::string get_activeScene_HAL();
+void set_activeScene_HAL(std::string anActiveScene);
+std::string get_activeGUIname_HAL();
+void set_activeGUIname_HAL(std::string anActiveGUIname);
+int get_activeGUIlist_HAL();
+void set_activeGUIlist_HAL(int anActiveGUIlist);
diff --git a/Platformio/hardware/windows_linux/preferencesStorage_hal_windows_linux.cpp b/Platformio/hardware/windows_linux/preferencesStorage_hal_windows_linux.cpp
index af5d257..5d45c89 100644
--- a/Platformio/hardware/windows_linux/preferencesStorage_hal_windows_linux.cpp
+++ b/Platformio/hardware/windows_linux/preferencesStorage_hal_windows_linux.cpp
@@ -1,31 +1,50 @@
 #include <string>
 
-std::string currentScene;
-std::string currentGUIname;
+enum GUIlists {
+// MAIN_GUI_LIST: we are in the main_gui_list (with the scene selector as first gui), either if a scene is active or not
+// SCENE_GUI_LIST: a scene is active and we are not in the main_gui_list. In that case, we try to use the scene specific gui list, if the scene defined one.
+  MAIN_GUI_LIST,
+  SCENE_GUI_LIST
+};
+
+/*
+Possible example:
+main_gui_list : "Scene selection", "Smart Home", "Settings", "IR Receiver"};
+
+"Off"        :
+"TV"         : "Numpad"
+"Fire TV"    : "Numpad",   "Settings"
+"Chromecast" : 
+"Apple TV"   : "Apple TV", "Settings", "IR Receiver"
+*/
+std::string activeScene;
+std::string activeGUIname;
+int activeGUIlist;
 
 void init_preferences_HAL(void) {
+  // set some values for tests
+  activeScene = "";              // "Off", "TV", "Fire TV", "Chromecast", "Apple TV";
+  activeGUIname = "";            // "Scene selection", "Smart Home", "Settings", "IR Receiver"    // "Numpad", "Apple TV"
+  activeGUIlist = MAIN_GUI_LIST; // // MAIN_GUI_LIST, SCENE_GUI_LIST;
 }
 void save_preferences_HAL(void) {
 }
 
-std::string get_currentScene_HAL() {
-  // if (currentScene == "") {
-  // // set here something if you need it for a test at startup
-  //   return "Apple TV";
-  // } else
-  {return currentScene;}
-
+std::string get_activeScene_HAL() {
+  return activeScene;
 }
-void set_currentScene_HAL(std::string aCurrentScene) {
-  currentScene = aCurrentScene;
+void set_activeScene_HAL(std::string anActiveScene) {
+  activeScene = anActiveScene;
 }
-std::string get_currentGUIname_HAL(){
-  // if (currentGUIname == "") {
-  // // set here something if you need it for a test at startup
-  //   return "IR Receiver"; // "Numpad"; // "Apple TV";
-  // } else
-  {return currentGUIname;}
+std::string get_activeGUIname_HAL(){
+  return activeGUIname;
 }
-void set_currentGUIname_HAL(std::string aCurrentGUIname) {
-  currentGUIname = aCurrentGUIname;
+void set_activeGUIname_HAL(std::string anActiveGUIname) {
+  activeGUIname = anActiveGUIname;
+}
+int get_activeGUIlist_HAL() {
+  return activeGUIlist;
+}
+void set_activeGUIlist_HAL(int anActiveGUIlist) {
+  activeGUIlist = anActiveGUIlist;
 }
diff --git a/Platformio/hardware/windows_linux/preferencesStorage_hal_windows_linux.h b/Platformio/hardware/windows_linux/preferencesStorage_hal_windows_linux.h
index f94f0f4..9f4d98e 100644
--- a/Platformio/hardware/windows_linux/preferencesStorage_hal_windows_linux.h
+++ b/Platformio/hardware/windows_linux/preferencesStorage_hal_windows_linux.h
@@ -5,7 +5,9 @@
 void init_preferences_HAL(void);
 void save_preferences_HAL(void);
 
-std::string get_currentScene_HAL();
-void set_currentScene_HAL(std::string aCurrentScene);
-std::string get_currentGUIname_HAL();
-void set_currentGUIname_HAL(std::string aCurrentGUIname);
+std::string get_activeScene_HAL();
+void set_activeScene_HAL(std::string anActiveScene);
+std::string get_activeGUIname_HAL();
+void set_activeGUIname_HAL(std::string anActiveGUIname);
+int get_activeGUIlist_HAL();
+void set_activeGUIlist_HAL(int anActiveGUIlist);
diff --git a/Platformio/src/applicationInternal/gui/guiBase.cpp b/Platformio/src/applicationInternal/gui/guiBase.cpp
index b96d232..c8e9f86 100644
--- a/Platformio/src/applicationInternal/gui/guiBase.cpp
+++ b/Platformio/src/applicationInternal/gui/guiBase.cpp
@@ -13,8 +13,6 @@ lv_obj_t* BluetoothLabel = NULL;
 lv_obj_t* BattPercentageLabel = NULL;
 lv_obj_t* BattIconLabel = NULL;
 lv_obj_t* SceneLabel = NULL;
-uint32_t currentTabID = -1; // id of the current tab
-uint32_t oldTabID = -1;
 
 lv_obj_t* tabview = NULL;
 // page indicator
@@ -28,8 +26,8 @@ lv_style_t panel_style;
 lv_style_t style_red_border;
 #endif
 
-void guis_doTabCreationAtStartup();
-void guis_doAfterSliding(int oldTabID, int newTabID, bool newGuiList);
+void guis_doTabCreationOnStartup();
+void guis_doTabCreationAfterSliding(int newTabID);
 
 // Helper Functions -----------------------------------------------------------------------------------------------------------------------
 
@@ -87,28 +85,28 @@ void tabview_content_is_scrolling_event_cb(lv_event_t* e){
 // -----------------------
 static bool waitBeforeActionAfterSlidingAnimationEnded = false;
 static unsigned long waitBeforeActionAfterSlidingAnimationEnded_timerStart;
+static int newTabID_forLateTabCreation;
 // This is the callback when the animation of the tab sliding ended
 static void tabview_animation_ready_cb(lv_anim_t* a) {
   // Unfortunately, the animation has not completely ended here. We cannot do the recreation of the tabs here.
   // We have to wait some more milliseconds or at least one cycle of lv_timer_handler();
   // calling lv_timer_handler(); here does not help
   // lv_timer_handler();
-  // guis_doAfterSliding(oldTabID, currentTabID, false);
+  // guis_doTabCreationAfterSliding(newTabID_forLateTabCreation);
 
   waitBeforeActionAfterSlidingAnimationEnded = true;
   waitBeforeActionAfterSlidingAnimationEnded_timerStart = millis();
 }
 
-// Update currentTabID when a new tab is selected
+// Update gui when a new tab is selected
 // this is a callback if the tabview is changed (LV_EVENT_VALUE_CHANGED)
 // Sent when a new tab is selected by sliding or clicking the tab button. lv_tabview_get_tab_act(tabview) returns the zero based index of the current tab.
 void tabview_tab_changed_event_cb(lv_event_t* e) {
   if (lv_event_get_code(e) == LV_EVENT_VALUE_CHANGED) {
     
-    oldTabID = currentTabID;
-    currentTabID = lv_tabview_get_tab_act(lv_event_get_target(e));
+    int newTabID = lv_tabview_get_tab_active((lv_obj_t*)lv_event_get_target(e));
 
-    // Wait until the animation ended, then call "guis_doAfterSliding(oldTabID, currentTabID, false);"
+    // Wait until the animation ended, then call "guis_doTabCreationAfterSliding(newTabID);"
     // https://forum.lvgl.io/t/delete-a-tab-after-the-tabview-scroll-animation-is-complete/3155/4
     lv_obj_t* myTabview = lv_event_get_target(e);
     lv_obj_t* tabContainer = lv_tabview_get_content(myTabview);
@@ -116,11 +114,12 @@ void tabview_tab_changed_event_cb(lv_event_t* e) {
     if(anim) {
       // Swipe is not yet complete. User released the touch screen, an animation will bring it to the end.
       // That's the normal (and only?) case for the tft touchscreen
+      newTabID_forLateTabCreation = newTabID;
       lv_anim_set_ready_cb(anim, tabview_animation_ready_cb);
     } else {
       // Swipe is complete, no additional animation is needed. Most likely only possible in simulator
       Serial.println("Change of tab detected, without animation at the end. Will directly do my job after sliding.");
-      guis_doAfterSliding(oldTabID, currentTabID, false);
+      guis_doTabCreationAfterSliding(newTabID);
     }
   }
 }
@@ -154,8 +153,8 @@ void init_gui(void) {
   lv_obj_set_style_bg_color(lv_scr_act(), lv_color_black(), LV_PART_MAIN);
   // set default height and position of main widgets
   setMainWidgetsHeightAndPosition();
-  // At startup, set current GUI according to get_currentGUIname(), and create the content of that tab (and the previous and the next) for the first time
-  guis_doTabCreationAtStartup();
+  // On startup, set current GUIname and GUIlist according to last state before going to sleep
+  guis_doTabCreationOnStartup();
   // memoryUsage bar
   init_gui_memoryUsage_bar();
   // status bar
@@ -288,12 +287,12 @@ void gui_loop(void) {
     waitBeforeActionAfterSlidingAnimationEnded = false;
   } else if (waitOneLoop) {
     waitOneLoop = false;
-    guis_doAfterSliding(oldTabID, currentTabID, false);
+    guis_doTabCreationAfterSliding(newTabID_forLateTabCreation);
   };
   // // as alternative, we could wait some milliseconds. But one cycle of gui_loop() works well.
   // if (waitBeforeActionAfterSlidingAnimationEnded) {
   //   if (millis() - waitBeforeActionAfterSlidingAnimationEnded_timerStart >= 5) {
-  //     guis_doAfterSliding(oldTabID, currentTabID, false);
+  //     guis_doTabCreationAfterSliding(newTabID_forLateTabCreation);
   //     waitBeforeActionAfterSlidingAnimationEnded = false;
   //   }
   // }
@@ -301,19 +300,25 @@ void gui_loop(void) {
   lv_timer_handler();
 }
 
-void guis_doTabCreationAtStartup() {
-  gui_memoryOptimizer_prepare_startup();
-
-  guis_doAfterSliding(-1, -1, false);
-}
-
-void guis_doAfterSliding(int oldTabID, int newTabID, bool newGuiList) {
-  // With parameter newGuiList it is signaled that we are changing from a scene specific list to the main list or vice versa
-  // In that case, we have to do special treatment because we are not simply sliding to the left or to the right, but we start newly with a different gui list.
-  gui_memoryOptimizer_doAfterSliding_deletionAndCreation(&tabview, oldTabID, newTabID, newGuiList, &panel, &img1, &img2);
-
+// ------------------------------------------------------------------------------------------------------------
+// There are several reasons why the tabs could get recreated. All are going through these functions in "guiBase.cpp", which are calling functions in "guiMemoryOptimizer.cpp"
+// 1. tab creation on startup (called by init_gui())
+void guis_doTabCreationOnStartup() {
+  Serial.printf("Startup: try to resume at scene \"%s\" with GUI \"%s\"\r\n", gui_memoryOptimizer_getActiveSceneName().c_str(), gui_memoryOptimizer_getActiveGUIname().c_str());
+  gui_memoryOptimizer_onStartup(&tabview, &panel, &img1, &img2);
   doLogMemoryUsage();
 }
+// 2. tab creation after sliding (called by tabview_tab_changed_event_cb())
+void guis_doTabCreationAfterSliding(int newTabID) {
+  gui_memoryOptimizer_afterSliding(&tabview, &panel, &img1, &img2, newTabID);
+  doLogMemoryUsage();
+}
+// 3. after gui list has changed (called by handleScene()), when switching between main_gui_list and scene specific list
+void guis_doTabCreationAfterGUIlistChanged(GUIlists newGUIlist) {
+  gui_memoryOptimizer_afterGUIlistChanged(&tabview, &panel, &img1, &img2, newGUIlist);
+  doLogMemoryUsage();
+}
+// ------------------------------------------------------------------------------------------------------------
 
 void setActiveTab(uint32_t index, lv_anim_enable_t anim_en, bool send_tab_changed_event) {
   // unsigned long startTime = millis();
diff --git a/Platformio/src/applicationInternal/gui/guiBase.h b/Platformio/src/applicationInternal/gui/guiBase.h
index eb7ceab..2a8c2a0 100644
--- a/Platformio/src/applicationInternal/gui/guiBase.h
+++ b/Platformio/src/applicationInternal/gui/guiBase.h
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <lvgl.h>
+#include "applicationInternal/gui/guiMemoryOptimizer.h"
 
 // used by memoryUsage.cpp
 extern lv_obj_t* MemoryUsageLabel;
@@ -15,7 +16,6 @@ extern lv_style_t panel_style;
 extern int tabviewTop;
 extern int tabviewHeight;
 extern int panelHeight;
-extern uint32_t currentTabID;
 // used by almost all gui_*.cpp
 extern lv_color_t color_primary;
 
@@ -32,10 +32,9 @@ void tabview_content_is_scrolling_event_cb(lv_event_t* e);
 void tabview_tab_changed_event_cb(lv_event_t* e);
 void sceneLabel_or_pageIndicator_event_cb(lv_event_t* e);
 void pageIndicator_navigate_event_cb(lv_event_t* e);
+void guis_doTabCreationAfterGUIlistChanged(GUIlists newGUIlist);
 void setActiveTab(uint32_t index, lv_anim_enable_t anim_en, bool send_tab_changed_event = false);
 // used by memoryUsage.cpp
 void showMemoryUsageBar(bool showBar);
 // used by commandHandler to show WiFi status
 void showWiFiConnected(bool connected);
-
-void guis_doAfterSliding(int oldTabID, int newTabID, bool newGuiList);
diff --git a/Platformio/src/applicationInternal/gui/guiMemoryOptimizer.cpp b/Platformio/src/applicationInternal/gui/guiMemoryOptimizer.cpp
index 8c03a70..e3a1643 100644
--- a/Platformio/src/applicationInternal/gui/guiMemoryOptimizer.cpp
+++ b/Platformio/src/applicationInternal/gui/guiMemoryOptimizer.cpp
@@ -1,47 +1,90 @@
 #include <lvgl.h>
 #include "applicationInternal/gui/guiBase.h"
+#include "applicationInternal/gui/guiMemoryOptimizer.h"
 #include "applicationInternal/gui/guiRegistry.h"
-#include "applicationInternal/scenes/sceneRegistry.h"
 #include "applicationInternal/hardware/hardwarePresenter.h"
+#include "applicationInternal/scenes/sceneRegistry.h"
 
-struct tab_in_memory {
+struct t_gui_on_tab {
   lv_obj_t* tab;
-  int listIndex;
-  std::string guiName;
+  std::string GUIname;
+  int gui_list_index;
+  int gui_list_index_previous;
 };
-tab_in_memory tabs_in_memory[3] = {{NULL, -1, ""}, {NULL, -1, ""}, {NULL, -1, ""}};
-// holds the ids of the tabs we had in memory before, so that we can determine the next or previous id
-int tabs_in_memory_previous_listIndex[3]= {-1 , -1, -1};
+struct t_gui_state {
+  // the next three are saved in the preferenceStorage every time they change
+  std::string activeScene_internalDontUse;
+  std::string activeGUIname_internalDontUse;
+  GUIlists activeGUIlist_internalDontUse;
+  // ---
+  int activeTabID = -1;      // id of the active tab (one of 0,1,2)
+  int oldTabID = -1;         // id of the tab before swiping (one of 0,1,2)
+  t_gui_on_tab gui_on_tab[3] = {{NULL, "", -1, -1}, {NULL, "", -1, -1}, {NULL, "", -1, -1}};
+};
+t_gui_state gui_state;
+
+// Both the gui_state and the preferenceStorage should know at any time the current state (scene, GUIname, and GUIlist)
+// preferenceStorage should know it because when going to sleep, it should persist the state in NVM.
+// So whenever values change, it should be done through these functions.
+// On startup, the gui_state is set by gui_memoryOptimizer_onStartup()
+std::string gui_memoryOptimizer_getActiveSceneName() {
+  gui_state.activeScene_internalDontUse = get_activeScene();
+  return gui_state.activeScene_internalDontUse;
+}
+void gui_memoryOptimizer_setActiveSceneName(std::string aSceneName) {
+  gui_state.activeScene_internalDontUse = aSceneName;
+  set_activeScene(aSceneName);
+}
+std::string gui_memoryOptimizer_getActiveGUIname() {
+  gui_state.activeGUIname_internalDontUse = get_activeGUIname();
+  return gui_state.activeGUIname_internalDontUse;
+}
+void gui_memoryOptimizer_setActiveGUIname(std::string aGUIname) {
+  gui_state.activeGUIname_internalDontUse = aGUIname;
+  set_activeGUIname(aGUIname);
+}
+GUIlists gui_memoryOptimizer_getActiveGUIlist() {
+  gui_state.activeGUIlist_internalDontUse = (GUIlists)get_activeGUIlist();
+  return gui_state.activeGUIlist_internalDontUse;
+}
+void gui_memoryOptimizer_setActiveGUIlist(GUIlists aGUIlist) {
+  gui_state.activeGUIlist_internalDontUse = aGUIlist;
+  set_activeGUIlist(aGUIlist);
+}
+
+int gui_memoryOptimizer_getActiveTabID() {
+  return gui_state.activeTabID;
+}
 
 bool gui_memoryOptimizer_isTabIDInMemory(int tabID) {
   // range check
   if ((tabID < 0) || (tabID >= 3)) {
     return false;
   }
-  return (tabs_in_memory[tabID].listIndex != -1);
+  return (gui_state.gui_on_tab[tabID].gui_list_index != -1);
 }
 
-bool gui_memoryOptimizer_isGUInameInMemory(std::string guiName) {
+bool gui_memoryOptimizer_isGUInameInMemory(std::string GUIname) {
   for (uint8_t index=0; index <= 2; index++) {
-    if (tabs_in_memory[index].guiName == guiName) {
+    if (gui_state.gui_on_tab[index].GUIname == GUIname) {
       return true;
     }
   }
   return false;
 }
 
-void notify_active_tabs_before_delete() {
+void notify_active_tabs_before_delete(t_gui_state *gui_state) {
   Serial.printf("  Will notify tabs about deletion\r\n");
   std::string nameOfTab;
   for (int index=0; index <= 2; index++) {
-    if (tabs_in_memory[index].listIndex == -1) {
+    if (gui_state->gui_on_tab[index].gui_list_index == -1) {
       Serial.printf("    Will not notify tab %d about deletion because it does not exist\r\n", index);
       continue;
     }
 
-    // For deletion, do not use the listIndex, but the name of the gui.
+    // For deletion, do not use the gui_list_index, but the name of the gui.
     // The gui_list might have changed (when switching from a scene specific list to the main list or vice versa), so index could have changed as well.
-    nameOfTab = tabs_in_memory[index].guiName;
+    nameOfTab = gui_state->gui_on_tab[index].GUIname;
     if (nameOfTab == "") {
       Serial.printf("    Will not notify tab %d about deletion because it is not set\r\n", index);
     } else if (registered_guis_byName_map.count(nameOfTab) == 0) {
@@ -53,7 +96,7 @@ void notify_active_tabs_before_delete() {
   }
 }
 
-void clear_tabview(lv_obj_t* tabview) {
+void clear_tabview(lv_obj_t* tabview, t_gui_state *gui_state) {
   if (tabview != NULL) {
     // first remove events for the tabview
     lv_obj_remove_event_cb(tabview, tabview_tab_changed_event_cb);
@@ -63,10 +106,10 @@ void clear_tabview(lv_obj_t* tabview) {
     tabview = NULL;
   }
 
-  // set struct tabs_in_memory to NULL
-  tabs_in_memory[0] = {NULL, -1, ""};
-  tabs_in_memory[1] = {NULL, -1, ""};
-  tabs_in_memory[2] = {NULL, -1, ""};
+  // the gui_list_index_previous is needed for setGUIlistIndicesToBeShown_afterSlide();
+  gui_state->gui_on_tab[0] = {NULL, "", -1, gui_state->gui_on_tab[0].gui_list_index};
+  gui_state->gui_on_tab[1] = {NULL, "", -1, gui_state->gui_on_tab[1].gui_list_index};
+  gui_state->gui_on_tab[2] = {NULL, "", -1, gui_state->gui_on_tab[2].gui_list_index};
 
 }
 
@@ -114,162 +157,161 @@ lv_obj_t* create_panel() {
 std::string get_name_of_gui_to_be_shown(int index) {
   if (index == -1) {
     return "";
-  } else if (index <= get_gui_list(get_currentScene())->size() -1) {
-    return get_gui_list(get_currentScene())->at(index);
+  } else if (index <= get_gui_list_active()->size() -1) {
+    return get_gui_list_active()->at(index);
   } else {
     return "";
   }
 }
 
-void create_new_tab(lv_obj_t* tabview, uint32_t tabs_in_memory_index) {
-  std::string nameOfTab = get_name_of_gui_to_be_shown(tabs_in_memory[tabs_in_memory_index].listIndex);
+void create_new_tab(lv_obj_t* tabview, t_gui_on_tab *gui_on_tab) {
+  std::string nameOfTab = get_name_of_gui_to_be_shown(gui_on_tab->gui_list_index);
 
   if (nameOfTab == "") {
-    Serial.printf("    Will not create new tab at index %d because no name was provided\r\n", tabs_in_memory_index);
+    Serial.printf("    Will not create new tab because no name was provided\r\n");
   } else if (registered_guis_byName_map.count(nameOfTab) == 0) {
-    Serial.printf("    Will not create new tab at index %d because name %s was not found in registry\r\n", tabs_in_memory_index, nameOfTab.c_str());
+    Serial.printf("    Will not create new tab because name %s was not found in registry\r\n", nameOfTab.c_str());
   } else {
-    Serial.printf("    Will create tab with name \"%s\" at index %d\r\n", nameOfTab.c_str(), tabs_in_memory_index);
+    Serial.printf("    Will create tab with name \"%s\" \r\n", nameOfTab.c_str());
     // save name of tab for deletion later
-    tabs_in_memory[tabs_in_memory_index].guiName = nameOfTab;
-    // create tab and save pointer to tab in tabs_in_memory
-    tabs_in_memory[tabs_in_memory_index].tab = lv_tabview_add_tab(tabview, nameOfTab.c_str());
+    gui_on_tab->GUIname = nameOfTab;
+    // create tab and save pointer to tab in gui_on_tab
+    gui_on_tab->tab = lv_tabview_add_tab(tabview, nameOfTab.c_str());
     // let the gui create it's content
-    registered_guis_byName_map.at(nameOfTab).this_create_tab_content(tabs_in_memory[tabs_in_memory_index].tab);
+    registered_guis_byName_map.at(nameOfTab).this_create_tab_content(gui_on_tab->tab);
   }
 }
 
-void doTabCreation_strategyMax3(lv_obj_t* tabview, uint32_t oldTabID, uint32_t newTabID) {
-  // create up to three tabs and the content of the tabs
-  /*
-  example: gui_list: 0 1 2 3 4
-  in memory  active
-  0 1 -1     0 <- first state, special case - also the initial state
-  0 1 2      1
-  1 2 3      1
-  2 3 4      1
-  3 4 -1     1 <- last state, special case
-  */
+// create up to three tabs and the content of the tabs
+/*
+example: gui_list: 0 1 2 3 4
+in memory  active
+0 1 -1     0 <- first state, special case - also the initial state
+0 1 2      1
+1 2 3      1
+2 3 4      1
+3 4 -1     1 <- last state, special case
+*/
+void setGUIlistIndicesToBeShown_forSpecificGUIlistIndex(int gui_list_index, t_gui_state *gui_state) {
+  // Set the gui_list_indeces to be shown for a specific gui_list_index
+  if (gui_list_index == 0) {
+    // first state
+    Serial.printf("  GUIlistIndices: will resume at specific index with \"first state\"\r\n");
+    gui_state->gui_on_tab[0] = {NULL, "", 0};
+    // take care if there is only one gui in list
+    gui_state->gui_on_tab[1] = {NULL, "", get_gui_list_active()->size() >= 2 ? 1 : -1};
+    gui_state->gui_on_tab[2] = {NULL, "", -1};
+    gui_state->activeTabID = 0;
+  } else if (gui_list_index == get_gui_list_active()->size() -1) {
+    // last state
+    Serial.printf("  GUIlistIndices: will resume at specific index with \"last state\"\r\n");
+    gui_state->gui_on_tab[0] = {NULL, "", gui_list_index -1};
+    gui_state->gui_on_tab[1] = {NULL, "", gui_list_index};
+    gui_state->gui_on_tab[2] = {NULL, "", -1};
+    gui_state->activeTabID = 1;
+  } else {
+    // any other state
+    Serial.printf("  GUIlistIndices: will resume at specific index with \"state between\"\r\n");
+    gui_state->gui_on_tab[0] = {NULL, "", gui_list_index -1};
+    gui_state->gui_on_tab[1] = {NULL, "", gui_list_index};
+    gui_state->gui_on_tab[2] = {NULL, "", gui_list_index +1};
+    gui_state->activeTabID = 1;
+  }
+}
 
-  int tabToBeActivated = -1;
+void setGUIlistIndicesToBeShown_forFirstGUIinGUIlist(t_gui_state *gui_state) {
+  Serial.printf("  GUIlistIndices: will show the first gui from \"gui_list\" as initial state\r\n");
+  // take care if there is no gui in list
+  gui_state->gui_on_tab[0] = {NULL, "", get_gui_list_active()->size() != 0 ? 0 : -1};
+  // take care if there is only one gui in list
+  gui_state->gui_on_tab[1] = {NULL, "", get_gui_list_active()->size() >= 2 ? 1 : -1};
+  gui_state->gui_on_tab[2] = {NULL, "", -1};
+  gui_state->activeTabID = 0;
+}
+
+void setGUIlistIndicesToBeShown_afterSlide(t_gui_state *gui_state) {
   int oldListIndex = -1;
-
-  if ((oldTabID == -1) && (newTabID == -1)) {
-    // This is the initialization after the ESP32 has booted.
-
-    if ((tabs_in_memory_previous_listIndex[0] < get_gui_list(get_currentScene())->size()) && (tabs_in_memory_previous_listIndex[0] != -1)) {
-      // In gui_memoryOptimizer_prepare_startup, the index of get_currentGUIname() in gui_list was saved, if found.
-      // We can resume at this old state.
-      oldListIndex = tabs_in_memory_previous_listIndex[0] ; 
-      if (oldListIndex == 0) {
-        // first state
-        Serial.printf("  Startup: will resume where we went to sleep with \"first state\"\r\n");
-        tabs_in_memory[0] = {NULL, 0};
-        // take care if there is only one gui in list
-        tabs_in_memory[1] = {NULL, get_gui_list(get_currentScene())->size() >= 2 ? 1 : -1};
-        tabs_in_memory[2] = {NULL, -1};
-        tabToBeActivated = 0;
-      } else if (oldListIndex == get_gui_list(get_currentScene())->size() -1) {
-        // last state
-        Serial.printf("  Startup: will resume where we went to sleep with \"last state\"\r\n");
-        tabs_in_memory[0] = {NULL, oldListIndex -1};
-        tabs_in_memory[1] = {NULL, oldListIndex};
-        tabs_in_memory[2] = {NULL, -1};
-        tabToBeActivated = 1;
-      } else {
-        // any other state
-        Serial.printf("  Startup: will resume where we went to sleep with \"state between\"\r\n");
-        tabs_in_memory[0] = {NULL, oldListIndex -1};
-        tabs_in_memory[1] = {NULL, oldListIndex};
-        tabs_in_memory[2] = {NULL, oldListIndex +1};
-        tabToBeActivated = 1;
-      }
-    } else {
-      Serial.printf("  Startup: cannot resume old state, so we will show the first tabs from \"gui_list\" as initial state\r\n");
-      // take care if there is no gui in list
-      tabs_in_memory[0] = {NULL, get_gui_list(get_currentScene())->size() != 0 ? 0 : -1};
-      // take care if there is only one gui in list
-      tabs_in_memory[1] = {NULL, get_gui_list(get_currentScene())->size() >= 2 ? 1 : -1};
-      tabs_in_memory[2] = {NULL, -1};
-      tabToBeActivated = 0;
-    }
-  } else if (oldTabID > newTabID) {
+ 
+  if (gui_state->oldTabID > gui_state->activeTabID) {
     // swipe to previous item in list
     Serial.printf("  Will swipe to previous item in list\r\n");
-    oldListIndex = tabs_in_memory_previous_listIndex[1];
+    oldListIndex = gui_state->gui_on_tab[1].gui_list_index_previous;
     if ((oldListIndex == 1)) {
       // next state is the "first state"
-      tabs_in_memory[0] = {NULL, 0};
-      tabs_in_memory[1] = {NULL, 1};
-      tabs_in_memory[2] = {NULL, -1};
-      tabToBeActivated = 0;
+      gui_state->gui_on_tab[0] = {NULL, "", 0};
+      gui_state->gui_on_tab[1] = {NULL, "", 1};
+      gui_state->gui_on_tab[2] = {NULL, "", -1};
+      gui_state->activeTabID = 0;
     } else {
-      tabs_in_memory[0] = {NULL, oldListIndex -2};
-      tabs_in_memory[1] = {NULL, oldListIndex -1};
-      tabs_in_memory[2] = {NULL, oldListIndex};
-      tabToBeActivated = 1;
+      gui_state->gui_on_tab[0] = {NULL, "", oldListIndex -2};
+      gui_state->gui_on_tab[1] = {NULL, "", oldListIndex -1};
+      gui_state->gui_on_tab[2] = {NULL, "", oldListIndex};
+      gui_state->activeTabID = 1;
     }
   } else {
     // swipe to next item in list
     Serial.printf("  Will swipe to next item in list\r\n");
-    if (tabs_in_memory_previous_listIndex[2] == -1) {
+    if (gui_state->gui_on_tab[2].gui_list_index_previous == -1) {
       // last state was the first state
-      oldListIndex = tabs_in_memory_previous_listIndex[0]; // is always 0
+      oldListIndex = gui_state->gui_on_tab[0].gui_list_index_previous; // is always 0
     } else {
-      oldListIndex = tabs_in_memory_previous_listIndex[1];
+      oldListIndex = gui_state->gui_on_tab[1].gui_list_index_previous;
     }
-    if (oldListIndex == get_gui_list(get_currentScene())->size() -2) {
+    if (oldListIndex == get_gui_list_active()->size() -2) {
       // next state is the "last state"
-      tabs_in_memory[0] = {NULL, oldListIndex};
-      tabs_in_memory[1] = {NULL, oldListIndex +1};
-      tabs_in_memory[2] = {NULL, -1};
-      tabToBeActivated = 1;
+      gui_state->gui_on_tab[0] = {NULL, "", oldListIndex};
+      gui_state->gui_on_tab[1] = {NULL, "", oldListIndex +1};
+      gui_state->gui_on_tab[2] = {NULL, "", -1};
+      gui_state->activeTabID = 1;
     } else {
-      tabs_in_memory[0] = {NULL, oldListIndex};
-      tabs_in_memory[1] = {NULL, oldListIndex +1};
-      tabs_in_memory[2] = {NULL, oldListIndex +2};
-      tabToBeActivated = 1;
+      gui_state->gui_on_tab[0] = {NULL, "", oldListIndex};
+      gui_state->gui_on_tab[1] = {NULL, "", oldListIndex +1};
+      gui_state->gui_on_tab[2] = {NULL, "", oldListIndex +2};
+      gui_state->activeTabID = 1;
     }
   }
+ 
+}
 
+void doTabCreation_strategyMax3(lv_obj_t* tabview, t_gui_state *gui_state) {
+  
   // create the tabs
-  Serial.printf("  Will create tabs. List indices of the three tabs are %d, %d, %d, tab nr %d will be activated\r\n", tabs_in_memory[0].listIndex, tabs_in_memory[1].listIndex, tabs_in_memory[2].listIndex, tabToBeActivated);
+  Serial.printf("  Will create tabs. List indices of the three tabs are %d, %d, %d, tab nr %d will be activated\r\n", gui_state->gui_on_tab[0].gui_list_index, gui_state->gui_on_tab[1].gui_list_index, gui_state->gui_on_tab[2].gui_list_index, gui_state->activeTabID);
   for (int i=0; i<3; i++) {
-    create_new_tab(tabview, i);
+    create_new_tab(tabview, &gui_state->gui_on_tab[i]);
   }
 
-  if (get_gui_list(get_currentScene())->size() > 0) {
-    std::string nameOfNewActiveTab = get_gui_list(get_currentScene())->at(tabs_in_memory[tabToBeActivated].listIndex);
+  if (get_gui_list_active()->size() > 0) {
+    std::string nameOfNewActiveTab = get_gui_list_active()->at(gui_state->gui_on_tab[gui_state->activeTabID].gui_list_index);
     Serial.printf("  New visible tab is \"%s\"\r\n", nameOfNewActiveTab.c_str());
 
-    // set the tab we swiped to as active
-    setActiveTab(tabToBeActivated, LV_ANIM_OFF);
-    set_currentGUIname(nameOfNewActiveTab);
-    currentTabID = tabToBeActivated;
+    // set active tab
+    setActiveTab(gui_state->activeTabID, LV_ANIM_OFF);
+    gui_memoryOptimizer_setActiveGUIname(nameOfNewActiveTab);
   }
 }
 
 LV_IMG_DECLARE(gradientLeft);
 LV_IMG_DECLARE(gradientRight);
 
-void getBreadcrumpPosition(uint8_t* breadcrumpPosition, std::string nameOfTab) {
+void getBreadcrumpPosition(uint8_t* breadcrumpPosition, std::string nameOfGUI) {
   *breadcrumpPosition = 0;
 
-  gui_list currentGUIlist = get_gui_list(get_currentScene());
+  gui_list gui_list_active = get_gui_list_active();
   uint8_t counter = 0;
-  for (std::vector<std::string>::iterator it = currentGUIlist->begin() ; it != currentGUIlist->end(); ++it) {
+  for (std::vector<std::string>::iterator it = gui_list_active->begin() ; it != gui_list_active->end(); ++it) {
     counter++;
-    if (*it == nameOfTab) {
+    if (*it == nameOfGUI) {
       *breadcrumpPosition = counter;
       return;
     }
   }
 }
 
-void fillPanelWithPageIndicator_strategyMax3(lv_obj_t* panel, lv_obj_t* img1, lv_obj_t* img2) {
+void fillPanelWithPageIndicator_strategyMax3(lv_obj_t* panel, lv_obj_t* img1, lv_obj_t* img2, t_gui_state *gui_state) {
   Serial.printf("  Will fill panel with page indicators\r\n");
 
-  if (get_gui_list(get_currentScene())->size() == 0) {
+  if (get_gui_list_active()->size() == 0) {
     Serial.printf("    no tab available, so no page indicators\r\n");
     // at least add the style
     lv_obj_add_style(panel, &panel_style, 0);
@@ -301,33 +343,33 @@ void fillPanelWithPageIndicator_strategyMax3(lv_obj_t* panel, lv_obj_t* img1, lv
   btn = lv_btn_create(panel);
   lv_obj_clear_flag(btn, LV_OBJ_FLAG_CLICKABLE);
   lv_obj_set_size(btn, 150, lv_pct(100));
-  if (tabs_in_memory[0].listIndex == 0) {
+  if (gui_state->gui_on_tab[0].gui_list_index == 0) {
     lv_obj_set_style_bg_color(btn, lv_color_black(), LV_PART_MAIN);
   } else {
     lv_obj_set_style_bg_color(btn, color_primary,    LV_PART_MAIN);
   }
 
-  uint8_t breadcrumpLength = get_gui_list(get_currentScene())->size();
+  uint8_t breadcrumpLength = get_gui_list_active()->size();
   uint8_t breadcrumpDotSize =  8; // should be an even number
   uint8_t breadcrumpDotDistance = 2; // should be an even number
   int8_t breadcrumpStartPositionX = (-1) * (breadcrumpLength -1) * (breadcrumpDotSize + breadcrumpDotDistance) / 2;
 
   // create the panel content for the three guis (or less) which are currently in memory
-  std::string nameOfTab;
+  std::string nameOfGUI;
   uint8_t breadcrumpPosition;
   for (int i=0; i<3; i++) {
-    if (tabs_in_memory[i].listIndex != -1) {
-      nameOfTab = tabs_in_memory[i].guiName;
-      getBreadcrumpPosition(&breadcrumpPosition, nameOfTab);
+    if (gui_state->gui_on_tab[i].gui_list_index != -1) {
+      nameOfGUI = gui_state->gui_on_tab[i].GUIname;
+      getBreadcrumpPosition(&breadcrumpPosition, nameOfGUI);
 
       // Create actual buttons for every tab
       lv_obj_t* btn = lv_btn_create(panel);
       // only if this is the button for the currently active tab, make it clickable to get to scene selection gui
-      if (nameOfTab == get_currentGUIname()) {
+      if (nameOfGUI == gui_memoryOptimizer_getActiveGUIname()) {
         lv_obj_add_flag(btn, LV_OBJ_FLAG_CLICKABLE);
         lv_obj_add_event_cb(btn, sceneLabel_or_pageIndicator_event_cb, LV_EVENT_CLICKED, NULL);
 
-      } else if ((i==0 || i==1) && (tabs_in_memory[i+1].listIndex != -1)) {
+      } else if ((i==0 || i==1) && (gui_state->gui_on_tab[i+1].gui_list_index != -1)) {
         // this is the button on the previous tab, which can be seen on the active tab
         // activate click to prev tab
         lv_obj_add_flag(btn, LV_OBJ_FLAG_CLICKABLE);
@@ -367,7 +409,7 @@ void fillPanelWithPageIndicator_strategyMax3(lv_obj_t* panel, lv_obj_t* img1, lv
       }
       lv_obj_t* label = lv_label_create(btn);
       lv_obj_set_style_text_font(label, &lv_font_montserrat_10, LV_PART_MAIN);
-      lv_label_set_text_fmt(label, "%s", nameOfTab.c_str());
+      lv_label_set_text_fmt(label, "%s", nameOfGUI.c_str());
       lv_obj_align(label, LV_ALIGN_BOTTOM_MID, 0, 6);
 
     }
@@ -377,8 +419,8 @@ void fillPanelWithPageIndicator_strategyMax3(lv_obj_t* panel, lv_obj_t* img1, lv
   btn = lv_btn_create(panel);
   lv_obj_clear_flag(btn, LV_OBJ_FLAG_CLICKABLE);
   lv_obj_set_size(btn, 150, lv_pct(100));
-  //   4 at last position                                                            4 at middle position                                                           only one tab available overall
-  if ((tabs_in_memory[2].listIndex == get_gui_list(get_currentScene())->size()-1) || (tabs_in_memory[1].listIndex == get_gui_list(get_currentScene())->size()-1) || (tabs_in_memory[1].listIndex == -1)) {
+  //   4 at last position                                                              4 at middle position                                                           only one tab available overall
+  if ((gui_state->gui_on_tab[2].gui_list_index == get_gui_list_active()->size()-1) || (gui_state->gui_on_tab[1].gui_list_index == get_gui_list_active()->size()-1) || (gui_state->gui_on_tab[1].gui_list_index == -1)) {
     lv_obj_set_style_bg_color(btn, lv_color_black(), LV_PART_MAIN);
   } else {
     lv_obj_set_style_bg_color(btn, color_primary,    LV_PART_MAIN);
@@ -419,71 +461,76 @@ void fillPanelWithPageIndicator_strategyMax3(lv_obj_t* panel, lv_obj_t* img1, lv
 
 }
 
-void gui_memoryOptimizer_prepare_startup() {
-  // find index of get_currentGUIname() in gui_list
-  for (int i=0; i<get_gui_list(get_currentScene())->size(); i++) {
-    if (get_gui_list(get_currentScene())->at(i) == get_currentGUIname()) {
-      Serial.printf("Startup: found GUI with name \"%s\" in \"gui_list\" at position %d\r\n", get_currentGUIname().c_str(), i);
-      // save position so that "guis_doAfterSliding" can use it
-      tabs_in_memory[0].listIndex = i;
-    }
-  }
+void gui_memoryOptimizer_notifyAndClear(lv_obj_t** tabview, lv_obj_t** panel, lv_obj_t** img1, lv_obj_t** img2, t_gui_state *gui_state) {
 
-  // if the gui was not found in main_gui_list, try to find it in scene specific list
-  if (tabs_in_memory[0].listIndex == -1) {
-    useSceneGUIlist = true;
-    for (int i=0; i<get_gui_list(get_currentScene())->size(); i++) {
-      if (get_gui_list(get_currentScene())->at(i) == get_currentGUIname()) {
-        Serial.printf("Startup: found GUI with name \"%s\" in scene specific \"gui_list\" at position %d\r\n", get_currentGUIname().c_str(), i);
-        // save position so that "guis_doAfterSliding" can use it
-        tabs_in_memory[0].listIndex = i;
-      }
-    }
-  }
-
-  // if the gui was still not found, reset useSceneGUIlist
-  if (tabs_in_memory[0].listIndex == -1) {
-    useSceneGUIlist = false;
-  }
+  // 1. notify old guis that they will be deleted so that they can persist their state if needed
+  notify_active_tabs_before_delete(gui_state);
+  // 2. clear current tabview and save gui_list_index_previous (needed for swipe)
+  clear_tabview(*tabview, gui_state);
+  // 3. clear current panel for page indicator
+  clear_panel(*panel, *img1, *img2);
 
 }
 
-void gui_memoryOptimizer_doAfterSliding_deletionAndCreation(lv_obj_t** tabview, int oldTabID, int newTabID, bool newGuiList, lv_obj_t** panel, lv_obj_t** img1, lv_obj_t** img2) {
+void gui_memoryOptimizer_doContentCreation(lv_obj_t** tabview, lv_obj_t** panel, lv_obj_t** img1, lv_obj_t** img2, t_gui_state *gui_state);
+
+// find the position of the current GUI in the gui list which was active last (both were automatically saved in the preferences) 
+void gui_memoryOptimizer_onStartup(lv_obj_t** tabview, lv_obj_t** panel, lv_obj_t** img1, lv_obj_t** img2) {
+
+  // Get last state from preferences and save it in gui_state
+  // So it is ok to call them without using the return values.
+  gui_memoryOptimizer_getActiveSceneName();
+  gui_memoryOptimizer_getActiveGUIname();
+  gui_memoryOptimizer_getActiveGUIlist();
+  
+  // 1. find last used gui
+  int gui_list_index = -1;
+  // find index of gui_memoryOptimizer_getActiveGUIname() in gui_list_active
+  for (int i=0; i<get_gui_list_active()->size(); i++) {
+    if (get_gui_list_active()->at(i) == gui_memoryOptimizer_getActiveGUIname()) {
+      Serial.printf("Startup: found GUI with name \"%s\" in \"gui_list_active\" at position %d\r\n", gui_memoryOptimizer_getActiveGUIname().c_str(), i);
+      gui_list_index = i;
+      break;
+    }
+  }
+  
+  // 2. set gui_list_indices and the tab to be activated
+  if ((gui_list_index >= 0) && (gui_list_index < get_gui_list_active()->size())) {
+    // gui was found
+    setGUIlistIndicesToBeShown_forSpecificGUIlistIndex(gui_list_index, &gui_state);
+
+  } else {
+    // gui was not found
+    Serial.printf("Startup: GUI with name \"%s\" was not found. Will start with first GUI of main_gui_list\r\n", gui_memoryOptimizer_getActiveGUIname().c_str());
+    gui_memoryOptimizer_setActiveGUIlist(MAIN_GUI_LIST);
+    setGUIlistIndicesToBeShown_forFirstGUIinGUIlist(&gui_state);
+
+  }  
+
+  // 3. create content
+  gui_memoryOptimizer_doContentCreation(tabview, panel, img1, img2, &gui_state);
+
+}
+
+void gui_memoryOptimizer_afterSliding(lv_obj_t** tabview, lv_obj_t** panel, lv_obj_t** img1, lv_obj_t** img2, int newTabID) {
+
   // Here the magic for dynamic creation and deletion of lvgl objects happens to keep memory usage low.
   // The next and previous tab must always be available in the tabview, because they can already been seen during the animation.
   // And you always need 3 tabs, otherwise you even could not slide to the next or previous tab.
   // So we always have 3 tabs.
   // After the animation, the tabview and hence all tabs are deleted and recreated.
 
-  // With parameter newGuiList it is signaled that we are changing from a scene specific list to the main list or vice versa
-  // In that case, we have to do special treatment because we are not simply sliding to the left or to the right, but we start newly with a different gui list.
-  // only called by guis_doTabCreationAtStartup():
-  //   oldTabID = -1, newTabID = -1, newGuiList = false
-  // called by handleScene()
-  //   oldTabID = -1, newTabID = -1, newGuiList = true
-
   Serial.printf("--- Start of tab deletion and creation\r\n");
 
-  bool isInitialization = ((oldTabID == -1) && (newTabID == -1));
-  if (isInitialization) {
-    Serial.printf("Startup: will initially create the tabs to be shown\r\n");
-  } else {
-    Serial.printf("Changing from oldTabID %d \"%s\" to newTabID %d \"%s\"\r\n",
-      oldTabID, get_gui_list(get_currentScene())->at(tabs_in_memory[oldTabID].listIndex).c_str(),
-      newTabID, get_gui_list(get_currentScene())->at(tabs_in_memory[newTabID].listIndex).c_str());
-  }
+  gui_state.oldTabID = gui_state.activeTabID;
+  gui_state.activeTabID = newTabID;
 
-  // Save the ids of the tabs we had in memory before. This is only used by doTabCreation_strategyMax3() to know where we come from and where we have to go to.
-  for (int i=0; i<3; i++) {
-    tabs_in_memory_previous_listIndex[i] = tabs_in_memory[i].listIndex;
-  }
+  Serial.printf("Changing from oldTabID %d \"%s\" to newTabID %d \"%s\"\r\n",
+    gui_state.oldTabID,    gui_state.gui_on_tab[gui_state.oldTabID].GUIname.c_str(),
+    gui_state.activeTabID, gui_state.gui_on_tab[gui_state.activeTabID].GUIname.c_str());
 
-  // the old tabs need to be notified that they will be deleted so that they can persist their state if needed
-  notify_active_tabs_before_delete();
-  // clear current tabview
-  clear_tabview(*tabview);
-  // clear current panel for page indicator
-  clear_panel(*panel, *img1, *img2);
+  // 1. notify old guis and clear tabview and panel
+  gui_memoryOptimizer_notifyAndClear(tabview, panel, img1, img2, &gui_state);
 
   // only optional: delete and create the whole screen. Not necessary.
   // Only used for a test. init_gui_status_bar() would need to be called again at a suitable place, because the status bar would also be deleted.
@@ -494,25 +541,44 @@ void gui_memoryOptimizer_doAfterSliding_deletionAndCreation(lv_obj_t** tabview,
   // lv_scr_load(newscr);
   // lv_obj_del(oldscr);
 
-  if (newGuiList) {
-    // If we are switching to a new gui list, then we need to set tabs_in_memory_previous_listIndex[0] = -1;
-    // Doing so, doTabCreation_strategyMax3() knows that we cannot resume an old state.
-    tabs_in_memory_previous_listIndex[0] = -1;
-  }
+  // 2. set gui_list_indices and the tab to be activated
+  setGUIlistIndicesToBeShown_afterSlide(&gui_state);
 
+  // 3. create content
+  gui_memoryOptimizer_doContentCreation(tabview, panel, img1, img2, &gui_state);
+}
+
+void gui_memoryOptimizer_afterGUIlistChanged(lv_obj_t** tabview, lv_obj_t** panel, lv_obj_t** img1, lv_obj_t** img2, GUIlists newGUIlist) {
+
+  Serial.printf("--- Will change to new gui_list\r\n");
+
+  // 1. notify old guis and clear tabview and panel
+  gui_memoryOptimizer_notifyAndClear(tabview, panel, img1, img2, &gui_state);
+
+  // 2. set gui_list_indices and the tab to be activated
+  gui_memoryOptimizer_setActiveGUIlist(newGUIlist);
+  setGUIlistIndicesToBeShown_forFirstGUIinGUIlist(&gui_state);
+
+  // 3. create content
+  gui_memoryOptimizer_doContentCreation(tabview, panel, img1, img2, &gui_state);
+
+}
+
+void gui_memoryOptimizer_doContentCreation(lv_obj_t** tabview, lv_obj_t** panel, lv_obj_t** img1, lv_obj_t** img2, t_gui_state *gui_state) {
   // recreate the tabview
   lv_obj_t* newTabview = create_tabview();
   *tabview = newTabview;
+  
   // Create the tabs. Use strategy "3 tabs at maximum" to keep memory usage low.
   // Set the tab we swiped to as active
-  doTabCreation_strategyMax3(*tabview, oldTabID, newTabID);
+  doTabCreation_strategyMax3(*tabview, gui_state);
 
   // Create the panel for the page indicator. Panel itself takes about 2136 bytes for three tabs.
   lv_obj_t* newPanel = create_panel();
   *panel = newPanel;
   *img1 = lv_img_create(lv_scr_act());
   *img2 = lv_img_create(lv_scr_act());
-  fillPanelWithPageIndicator_strategyMax3(*panel, *img1, *img2);
+  fillPanelWithPageIndicator_strategyMax3(*panel, *img1, *img2, gui_state);
 
   // now, as the correct tab is active, register again the events for the tabview
   lv_obj_add_event_cb(*tabview, tabview_tab_changed_event_cb, LV_EVENT_VALUE_CHANGED, NULL);
diff --git a/Platformio/src/applicationInternal/gui/guiMemoryOptimizer.h b/Platformio/src/applicationInternal/gui/guiMemoryOptimizer.h
index 83a87c4..47ec812 100644
--- a/Platformio/src/applicationInternal/gui/guiMemoryOptimizer.h
+++ b/Platformio/src/applicationInternal/gui/guiMemoryOptimizer.h
@@ -1,6 +1,26 @@
 #pragma once
+#include <string>
+#include <lvgl.h>
 
-void gui_memoryOptimizer_prepare_startup();
-void gui_memoryOptimizer_doAfterSliding_deletionAndCreation(lv_obj_t** tabview, int oldTabID, int newTabID, bool newGuiList, lv_obj_t** panel, lv_obj_t** img1, lv_obj_t** img2);
+enum GUIlists {
+// MAIN_GUI_LIST: we are in the main_gui_list (with the scene selector as first gui), either if a scene is active or not
+// SCENE_GUI_LIST: a scene is active and we are not in the main_gui_list. In that case, we try to use the scene specific gui list, if the scene defined one.
+  MAIN_GUI_LIST,
+  SCENE_GUI_LIST
+};
+
+void gui_memoryOptimizer_onStartup(lv_obj_t** tabview, lv_obj_t** panel, lv_obj_t** img1, lv_obj_t** img2);
+void gui_memoryOptimizer_afterSliding(lv_obj_t** tabview, lv_obj_t** panel, lv_obj_t** img1, lv_obj_t** img2, int newTabID);
+void gui_memoryOptimizer_afterGUIlistChanged(lv_obj_t** tabview, lv_obj_t** panel, lv_obj_t** img1, lv_obj_t** img2, GUIlists newGUIlist);
+
+int gui_memoryOptimizer_getActiveTabID();
 bool gui_memoryOptimizer_isTabIDInMemory(int tabID);
-bool gui_memoryOptimizer_isGUInameInMemory(std::string guiName);
+bool gui_memoryOptimizer_isGUInameInMemory(std::string GUIname);
+
+std::string gui_memoryOptimizer_getActiveSceneName();
+void gui_memoryOptimizer_setActiveSceneName(std::string aSceneName);
+std::string gui_memoryOptimizer_getActiveGUIname();
+void gui_memoryOptimizer_setActiveGUIname(std::string aGUIname);
+GUIlists gui_memoryOptimizer_getActiveGUIlist();
+void gui_memoryOptimizer_setActiveGUIlist(GUIlists aGUIlist);
+
diff --git a/Platformio/src/applicationInternal/hardware/hardwarePresenter.cpp b/Platformio/src/applicationInternal/hardware/hardwarePresenter.cpp
index eeb20b3..4a78631 100644
--- a/Platformio/src/applicationInternal/hardware/hardwarePresenter.cpp
+++ b/Platformio/src/applicationInternal/hardware/hardwarePresenter.cpp
@@ -26,17 +26,23 @@ void init_preferences(void) {
 void save_preferences(void) {
   save_preferences_HAL();
 };
-std::string get_currentScene() {
-  return get_currentScene_HAL();
+std::string get_activeScene() {
+  return get_activeScene_HAL();
 }
-void set_currentScene(std::string aCurrentScene) {
-  set_currentScene_HAL(aCurrentScene);
+void set_activeScene(std::string anActiveScene) {
+  set_activeScene_HAL(anActiveScene);
 }
-std::string get_currentGUIname() {
-  return get_currentGUIname_HAL();
+std::string get_activeGUIname() {
+  return get_activeGUIname_HAL();
 }
-void set_currentGUIname(std::string aCurrentGUIname) {
-  set_currentGUIname_HAL(aCurrentGUIname);
+void set_activeGUIname(std::string anActiveGUIname) {
+  set_activeGUIname_HAL(anActiveGUIname);
+}
+int get_activeGUIlist() {
+  return get_activeGUIlist_HAL();
+}
+void set_activeGUIlist(int anActiveGUIlist) {
+  set_activeGUIlist_HAL(anActiveGUIlist);
 }
 
 // --- user led ---------------------------------------------------------------
diff --git a/Platformio/src/applicationInternal/hardware/hardwarePresenter.h b/Platformio/src/applicationInternal/hardware/hardwarePresenter.h
index 1145f1c..f01111e 100644
--- a/Platformio/src/applicationInternal/hardware/hardwarePresenter.h
+++ b/Platformio/src/applicationInternal/hardware/hardwarePresenter.h
@@ -10,10 +10,12 @@ void init_hardware_general(void);
 // --- preferences ------------------------------------------------------------
 void init_preferences(void);
 void save_preferences(void);
-std::string get_currentScene();
-void set_currentScene(std::string aCurrentScene);
-std::string get_currentGUIname();
-void set_currentGUIname(std::string aCurrentGUIname);
+std::string get_activeScene();
+void set_activeScene(std::string anActiveScene);
+std::string get_activeGUIname();
+void set_activeGUIname(std::string anActiveGUIname);
+int get_activeGUIlist();
+void set_activeGUIlist(int anActiveGUIlist);
 
 // --- user led ---------------------------------------------------------------
 void init_userled(void);
diff --git a/Platformio/src/applicationInternal/keys.cpp b/Platformio/src/applicationInternal/keys.cpp
index 75f2241..f46cdcb 100644
--- a/Platformio/src/applicationInternal/keys.cpp
+++ b/Platformio/src/applicationInternal/keys.cpp
@@ -1,7 +1,8 @@
 #include <string>
+#include "applicationInternal/gui/guiMemoryOptimizer.h"
+#include "applicationInternal/hardware/hardwarePresenter.h"
 #include "applicationInternal/scenes/sceneRegistry.h"
 #include "applicationInternal/commandHandler.h"
-#include "applicationInternal/hardware/hardwarePresenter.h"
 
 const uint8_t ROWS = 5; //five rows
 const uint8_t COLS = 5; //five columns
@@ -33,7 +34,7 @@ void doShortPress(char keyChar, int keyCode){
   if ((currentMillis - lastTimeSent[keyCode/ROWS][keyCode%ROWS]) > repeatRate) {
     lastTimeSent[keyCode/ROWS][keyCode%ROWS] = currentMillis;
 
-    uint16_t command = get_command_short(get_currentScene(), keyChar);
+    uint16_t command = get_command_short(gui_memoryOptimizer_getActiveSceneName(), keyChar);
     if (command != COMMAND_UNKNOWN) {
       Serial.printf("key: key '%c', will use command '%u'\r\n", keyChar, command);
       executeCommand(command);
@@ -44,7 +45,7 @@ void doShortPress(char keyChar, int keyCode){
 }
 
 void doLongPress(char keyChar, int keyCode){
-  uint16_t command = get_command_long(get_currentScene(), keyChar);
+  uint16_t command = get_command_long(gui_memoryOptimizer_getActiveSceneName(), keyChar);
   if (command != COMMAND_UNKNOWN) {
     Serial.printf("key: key '%c' (long press), will use command '%u'\r\n", keyChar, command);
     executeCommand(command);
@@ -70,11 +71,11 @@ void keypad_loop(void) {
     if (keypad_keys[i].kstate == PRESSED) {
       // Serial.println("pressed");
       
-      if ((get_key_repeatMode(get_currentScene(), keyChar) == SHORT) && (lastKeyState[keyCode/ROWS][keyCode%ROWS] != PRESSED)) {
+      if ((get_key_repeatMode(gui_memoryOptimizer_getActiveSceneName(), keyChar) == SHORT) && (lastKeyState[keyCode/ROWS][keyCode%ROWS] != PRESSED)) {
         // Serial.printf("key: PRESSED of SHORT key %c (%d)\r\n", keyChar, keyCode);
         doShortPress(keyChar, keyCode);
       
-      } else if ((get_key_repeatMode(get_currentScene(), keyChar) == SHORT_REPEATED) && (lastKeyState[keyCode/ROWS][keyCode%ROWS] != PRESSED)) { // here do not repeat it too early, do the repeat only in HOLD
+      } else if ((get_key_repeatMode(gui_memoryOptimizer_getActiveSceneName(), keyChar) == SHORT_REPEATED) && (lastKeyState[keyCode/ROWS][keyCode%ROWS] != PRESSED)) { // here do not repeat it too early, do the repeat only in HOLD
         // Serial.printf("key: PRESSED of SHORT_REPEATED key %c (%d)\r\n", keyChar, keyCode);
         doShortPress(keyChar, keyCode);
 
@@ -84,13 +85,13 @@ void keypad_loop(void) {
     } else if (keypad_keys[i].kstate == HOLD) {
       // Serial.println("hold");
       
-      if ((get_key_repeatMode(get_currentScene(), keyChar) == SHORTorLONG) && (lastKeyState[keyCode/ROWS][keyCode%ROWS] != HOLD)) {
+      if ((get_key_repeatMode(gui_memoryOptimizer_getActiveSceneName(), keyChar) == SHORTorLONG) && (lastKeyState[keyCode/ROWS][keyCode%ROWS] != HOLD)) {
         // Serial.printf("key: HOLD of SHORTorLONG key %c (%d)\r\n", keyChar, keyCode);
         // Serial.printf("will set keyIsHold to TRUE for keycode %d\r\n", keyCode);
         keyIsHold[keyCode/ROWS][keyCode%ROWS] = true;
         doLongPress(keyChar, keyCode);
       
-      } else if (get_key_repeatMode(get_currentScene(), keyChar) == SHORT_REPEATED) { // this is the only case where we do not check the lastKeyState, because here it is intended to repeat the action
+      } else if (get_key_repeatMode(gui_memoryOptimizer_getActiveSceneName(), keyChar) == SHORT_REPEATED) { // this is the only case where we do not check the lastKeyState, because here it is intended to repeat the action
         // Serial.printf("key: HOLD of SHORT_REPEATED key %c (%d)\r\n", keyChar, keyCode);
         doShortPress(keyChar, keyCode);
 
@@ -99,7 +100,7 @@ void keypad_loop(void) {
 
     } else if (keypad_keys[i].kstate == RELEASED) {
       // Serial.println("released");
-      if ((get_key_repeatMode(get_currentScene(), keyChar) == SHORTorLONG) && !keyIsHold[keyCode/ROWS][keyCode%ROWS] && (lastKeyState[keyCode/ROWS][keyCode%ROWS] != RELEASED)) {
+      if ((get_key_repeatMode(gui_memoryOptimizer_getActiveSceneName(), keyChar) == SHORTorLONG) && !keyIsHold[keyCode/ROWS][keyCode%ROWS] && (lastKeyState[keyCode/ROWS][keyCode%ROWS] != RELEASED)) {
         // Serial.printf("value of keyIsHold for keycode %d is %d\r\n", keyCode, keyIsHold[keyCode/ROWS][keyCode%ROWS]);
         // Serial.printf("key: RELEASED of SHORTorLONG key %c (%d)\r\n", keyChar, keyCode);
         doShortPress(keyChar, keyCode);
diff --git a/Platformio/src/applicationInternal/scenes/sceneHandler.cpp b/Platformio/src/applicationInternal/scenes/sceneHandler.cpp
index 8e35b94..fc0f4aa 100644
--- a/Platformio/src/applicationInternal/scenes/sceneHandler.cpp
+++ b/Platformio/src/applicationInternal/scenes/sceneHandler.cpp
@@ -7,6 +7,12 @@
 #include "applicationInternal/commandHandler.h"
 #include "scenes/scene__default.h"
 
+void setLabelActiveScene() {
+  if ((SceneLabel != NULL) && sceneExists(gui_memoryOptimizer_getActiveSceneName())) {
+    lv_label_set_text(SceneLabel, gui_memoryOptimizer_getActiveSceneName().c_str());
+  }
+}
+
 void handleScene(uint16_t command, commandData commandData, std::string additionalPayload = "") {
 
   // FORCE can be either as second payload in commandData
@@ -25,27 +31,26 @@ void handleScene(uint16_t command, commandData commandData, std::string addition
 
   // do not really switch scene, but show sceneSelection gui. From that on, we are in the main_gui_list.
   if (scene_name == scene_name_selection) {
-    useSceneGUIlist = false;
-    guis_doAfterSliding(-1, -1, true);
+    guis_doTabCreationAfterGUIlistChanged(MAIN_GUI_LIST);
     return;
   }
 
   // do not switch scene, but navigate to the prev or next gui in the currently active list of guis
   if ((scene_name == scene_gui_next) || (scene_name == scene_gui_prev)) {
     if (scene_name == scene_gui_prev) {
-      if (currentTabID == 0) {
+      if (gui_memoryOptimizer_getActiveTabID() == 0) {
         Serial.println("scene: cannot navigate to prev gui, because there is none");
       } else {
         Serial.println("scene: will navigate to prev gui");
-        setActiveTab(currentTabID -1, LV_ANIM_ON, true);
+        setActiveTab(gui_memoryOptimizer_getActiveTabID() -1, LV_ANIM_ON, true);
       }
 
     } else if (scene_name == scene_gui_next) {
-      if (!gui_memoryOptimizer_isTabIDInMemory(currentTabID +1)) {
+      if (!gui_memoryOptimizer_isTabIDInMemory(gui_memoryOptimizer_getActiveTabID() +1)) {
         Serial.println("scene: cannot navigate to next gui, because there is none");
       } else {
         Serial.println("scene: will navigate to next gui");
-        setActiveTab(currentTabID +1, LV_ANIM_ON, true);
+        setActiveTab(gui_memoryOptimizer_getActiveTabID() +1, LV_ANIM_ON, true);
       }
 
     }
@@ -57,15 +62,15 @@ void handleScene(uint16_t command, commandData commandData, std::string addition
     Serial.printf("scene: cannot start scene %s, because it is unknown\r\n", scene_name.c_str());
     return;
   } else {
-    Serial.printf("scene: will switch from old scene %s to new scene %s\r\n", get_currentScene().c_str(), scene_name.c_str());
+    Serial.printf("scene: will switch from old scene %s to new scene %s\r\n", gui_memoryOptimizer_getActiveSceneName().c_str(), scene_name.c_str());
   }
 
   // do not activate the same scene again, only when forced to do so (e.g. by long press on the gui or when selected by hardware key)
   bool callEndAndStartSequences;
-  if ((scene_name == get_currentScene()) && ((isForcePayload != "FORCE") && (additionalPayload != "FORCE"))) {
+  if ((scene_name == gui_memoryOptimizer_getActiveSceneName()) && ((isForcePayload != "FORCE") && (additionalPayload != "FORCE"))) {
     Serial.printf("scene: will not start scene again, because it is already active\r\n");
     callEndAndStartSequences = false;
-  } else if ((scene_name == get_currentScene()) && ((isForcePayload == "FORCE") || (additionalPayload == "FORCE"))) {
+  } else if ((scene_name == gui_memoryOptimizer_getActiveSceneName()) && ((isForcePayload == "FORCE") || (additionalPayload == "FORCE"))) {
     Serial.printf("scene: scene is already active, but FORCE was set, so start scene again\r\n");
     callEndAndStartSequences = true;
   } else {
@@ -78,13 +83,13 @@ void handleScene(uint16_t command, commandData commandData, std::string addition
 
   if (callEndAndStartSequences) {
     // end old scene
-    if (!sceneExists(get_currentScene()) && (get_currentScene() != "")) {
-      Serial.printf("scene: WARNING: cannot end scene %s, because it is unknown\r\n", get_currentScene().c_str());
+    if (!sceneExists(gui_memoryOptimizer_getActiveSceneName()) && (gui_memoryOptimizer_getActiveSceneName() != "")) {
+      Serial.printf("scene: WARNING: cannot end scene %s, because it is unknown\r\n", gui_memoryOptimizer_getActiveSceneName().c_str());
   
     } else {
-      if (get_currentScene() != "") {
-        Serial.printf("scene: will call end sequence for scene %s\r\n", get_currentScene().c_str());
-        scene_end_sequence_from_registry(get_currentScene());
+      if (gui_memoryOptimizer_getActiveSceneName() != "") {
+        Serial.printf("scene: will call end sequence for scene %s\r\n", gui_memoryOptimizer_getActiveSceneName().c_str());
+        scene_end_sequence_from_registry(gui_memoryOptimizer_getActiveSceneName());
       }
   
     }
@@ -94,19 +99,12 @@ void handleScene(uint16_t command, commandData commandData, std::string addition
     scene_start_sequence_from_registry(scene_name);
   }
 
-  set_currentScene(scene_name);
+  gui_memoryOptimizer_setActiveSceneName(scene_name);
 
-  if (SceneLabel != NULL) {lv_label_set_text(SceneLabel, get_currentScene().c_str());}
+  if (SceneLabel != NULL) {lv_label_set_text(SceneLabel, gui_memoryOptimizer_getActiveSceneName().c_str());}
 
-  Serial.printf("scene: scene handling finished, new scene %s is active\r\n", get_currentScene().c_str());
+  Serial.printf("scene: scene handling finished, new scene %s is active\r\n", gui_memoryOptimizer_getActiveSceneName().c_str());
 
-  useSceneGUIlist = true;
-  // recreate the gui based on the current scene
-  guis_doAfterSliding(-1, -1, true);
+  guis_doTabCreationAfterGUIlistChanged(SCENE_GUI_LIST);
 }
 
-void setLabelCurrentScene() {
-  if ((SceneLabel != NULL) && sceneExists(get_currentScene())) {
-    lv_label_set_text(SceneLabel, get_currentScene().c_str());
-  }
-}
diff --git a/Platformio/src/applicationInternal/scenes/sceneHandler.h b/Platformio/src/applicationInternal/scenes/sceneHandler.h
index 16c6c7b..ef2e217 100644
--- a/Platformio/src/applicationInternal/scenes/sceneHandler.h
+++ b/Platformio/src/applicationInternal/scenes/sceneHandler.h
@@ -3,5 +3,5 @@
 #include <string>
 #include "applicationInternal/commandHandler.h"
 
+void setLabelActiveScene();
 void handleScene(uint16_t command, commandData commandData, std::string additionalPayload = "");
-void setLabelCurrentScene();
diff --git a/Platformio/src/applicationInternal/scenes/sceneRegistry.cpp b/Platformio/src/applicationInternal/scenes/sceneRegistry.cpp
index c1be9d8..50162ec 100644
--- a/Platformio/src/applicationInternal/scenes/sceneRegistry.cpp
+++ b/Platformio/src/applicationInternal/scenes/sceneRegistry.cpp
@@ -1,16 +1,12 @@
 #include <map>
 #include <stdexcept>
-#include "applicationInternal/commandHandler.h"
-#include "applicationInternal/scenes/sceneRegistry.h"
+#include "applicationInternal/gui/guiMemoryOptimizer.h"
 #include "applicationInternal/hardware/hardwarePresenter.h"
+#include "applicationInternal/scenes/sceneRegistry.h"
+#include "applicationInternal/commandHandler.h"
 // scenes
 #include "scenes/scene__default.h"
 
-// If useSceneGUIlist == true, then a scene is active and we are not in the main_gui_list (with the scene selector as first gui).
-//   In that case, we try to use the scene specific gui list, if the scene defined one.
-// If useSceneGUIlist == false, then we are in the main_gui_list, either if a scene is active or not.
-bool useSceneGUIlist = false;
-
 // https://stackoverflow.com/questions/840501/how-do-function-pointers-in-c-work
 struct scene_definition {
   scene_setKeys this_scene_setKeys;
@@ -90,7 +86,7 @@ void scene_end_sequence_from_registry(std::string sceneName) {
 
 repeatModes get_key_repeatMode(std::string sceneName, char keyChar) {
   try {
-    // look if the map of the current scene has a definition for it
+    // look if the map of the active scene has a definition for it
     if ((registered_scenes.count(sceneName) > 0) && (registered_scenes.at(sceneName).this_key_repeatModes->count(keyChar) > 0)) {
       // Serial.printf("get_key_repeatMode: will use key from scene %s\r\n", sceneName.c_str());
       return registered_scenes.at(sceneName).this_key_repeatModes->at(keyChar);
@@ -114,7 +110,7 @@ repeatModes get_key_repeatMode(std::string sceneName, char keyChar) {
 
 uint16_t get_command_short(std::string sceneName, char keyChar) {
   try {
-    // look if the map of the current scene has a definition for it
+    // look if the map of the active scene has a definition for it
     if ((registered_scenes.count(sceneName) > 0) && (registered_scenes.at(sceneName).this_key_commands_short->count(keyChar) > 0)) {
       // Serial.printf("get_command_short: will use key from scene %s\r\n", sceneName.c_str());
       return registered_scenes.at(sceneName).this_key_commands_short->at(keyChar);
@@ -139,7 +135,7 @@ uint16_t get_command_short(std::string sceneName, char keyChar) {
 
 uint16_t get_command_long(std::string sceneName, char keyChar) {
   try {
-    // look if the map of the current scene has a definition for it
+    // look if the map of the active scene has a definition for it
     if ((registered_scenes.count(sceneName) > 0) && (registered_scenes.at(sceneName).this_key_commands_long->count(keyChar) > 0)) {
       // Serial.printf("get_command_long: will use key from scene %s\r\n", sceneName.c_str());
       return registered_scenes.at(sceneName).this_key_commands_long->at(keyChar);
@@ -162,40 +158,44 @@ uint16_t get_command_long(std::string sceneName, char keyChar) {
 
 }
 
-gui_list get_gui_list(std::string sceneName) {
+gui_list get_gui_list(GUIlists gui_list) {
   try {
-    // If useSceneGUIlist == true, then a scene is active and we are not in the main_gui_list (with the scene selector as first gui).
+    // If gui_list == MAIN_GUI_LIST, then we are in the main_gui_list, either if a scene is active or not.
+    // If gui_list == SCENE_GUI_LIST, then a scene is active and we are not in the main_gui_list (with the scene selector as first gui).
     //   In that case, we try to use the scene specific gui list, if the scene defined one.
-    // If useSceneGUIlist == false, then we are in the main_gui_list, either if a scene is active or not.
 
-    #if (USE_SCENE_SPECIFIC_GUI_LIST != 0)
-    // look if the current scene has a definition for a gui list
-    if (useSceneGUIlist &&
-        (registered_scenes.count(sceneName) > 0) && (registered_scenes.at(sceneName).this_gui_list != NULL)) {
-      // Serial.printf("get_gui_list: will use gui_list from scene %s\r\n", sceneName.c_str());
-      return registered_scenes.at(sceneName).this_gui_list;
-    
-    // if there is no scene specific gui list, simply return the main_gui_list
-    } else {
-      // Serial.printf("get_gui_list: will use main_gui_list\r\n");
+    if (gui_list == MAIN_GUI_LIST) {
       return &main_gui_list;
-    
-    }
-    #else
-    // never use scene specific gui list
-    return &main_gui_list;
-    #endif
+
+    } else {
+      #if (USE_SCENE_SPECIFIC_GUI_LIST != 0)
+        // look if the active scene has a definition for a gui list
+        if ((registered_scenes.count(gui_memoryOptimizer_getActiveSceneName()) > 0) && (registered_scenes.at(gui_memoryOptimizer_getActiveSceneName()).this_gui_list != NULL)) {
+          // Serial.printf("get_gui_list: will use gui_list from scene %s\r\n", sceneName.c_str());
+          return registered_scenes.at(gui_memoryOptimizer_getActiveSceneName()).this_gui_list;
+        } else {
+          // no scene specific gui list was defined
+          return &main_gui_list;
+        }
+      #else
+        // never use scene specific gui list
+        return &main_gui_list;
+      #endif
+    }  
   }
   catch (const std::out_of_range& oor) {
     Serial.printf("get_gui_list: internal error, sceneName not registered\r\n");
     return NULL;
   }
+}
 
+gui_list get_gui_list_active() {
+  return get_gui_list(gui_memoryOptimizer_getActiveGUIlist());
 }
 
 uint16_t get_activate_scene_command(std::string sceneName) {
   try {
-    // look if the current scene is known
+    // look if the active scene is known
     if ((registered_scenes.count(sceneName) > 0)) {
       // Serial.printf("get_activate_scene_command: will use activate_scene_command from scene %s\r\n", sceneName.c_str());
       return registered_scenes.at(sceneName).this_activate_scene_command;
diff --git a/Platformio/src/applicationInternal/scenes/sceneRegistry.h b/Platformio/src/applicationInternal/scenes/sceneRegistry.h
index dbc8f56..beb045a 100644
--- a/Platformio/src/applicationInternal/scenes/sceneRegistry.h
+++ b/Platformio/src/applicationInternal/scenes/sceneRegistry.h
@@ -6,8 +6,6 @@
 #include <vector>
 #include "applicationInternal/keys.h"
 
-extern bool useSceneGUIlist;
-
 typedef std::vector<std::string> t_gui_list;
 typedef std::vector<std::string> t_scene_list;
 
@@ -37,7 +35,7 @@ void scene_end_sequence_from_registry(std::string sceneName);
 repeatModes get_key_repeatMode(std::string sceneName, char keyChar);
 uint16_t get_command_short(std::string sceneName, char keyChar);
 uint16_t get_command_long(std::string sceneName, char keyChar);
-gui_list get_gui_list(std::string sceneName);
+gui_list get_gui_list_active();
 uint16_t get_activate_scene_command(std::string sceneName);
 scene_list get_scenes_on_sceneSelectionGUI();
 void set_scenes_on_sceneSelectionGUI(t_scene_list a_scene_list);
diff --git a/Platformio/src/guis/gui_numpad.cpp b/Platformio/src/guis/gui_numpad.cpp
index 6bb2e96..a853ffa 100644
--- a/Platformio/src/guis/gui_numpad.cpp
+++ b/Platformio/src/guis/gui_numpad.cpp
@@ -18,12 +18,12 @@ static void virtualKeypad_event_cb(lv_event_t* e) {
   
   int user_data = (intptr_t)(target->user_data);
   // send corrensponding number
-  if (get_currentScene() == scene_name_TV) {
+  if (gui_memoryOptimizer_getActiveSceneName() == scene_name_TV) {
     uint16_t virtualKeyMapTVNumbers[10] = {SAMSUNG_NUM_1, SAMSUNG_NUM_2, SAMSUNG_NUM_3, SAMSUNG_NUM_4, SAMSUNG_NUM_5, SAMSUNG_NUM_6, SAMSUNG_NUM_7, SAMSUNG_NUM_8, SAMSUNG_NUM_9, SAMSUNG_NUM_0};
     uint16_t command = virtualKeyMapTVNumbers[user_data];
     executeCommand(command);
 
-  } else if (get_currentScene() == scene_name_fireTV) {
+  } else if (gui_memoryOptimizer_getActiveSceneName() == scene_name_fireTV) {
     int virtualKeyMapFireTVNumbers[10] = {0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0x0};
     int number = virtualKeyMapFireTVNumbers[user_data];
     std::string numberStr = std::to_string(number);
diff --git a/Platformio/src/main.cpp b/Platformio/src/main.cpp
index 0515123..33ff548 100644
--- a/Platformio/src/main.cpp
+++ b/Platformio/src/main.cpp
@@ -125,7 +125,7 @@ int main(int argc, char *argv[]) {
   #endif
   // init GUI - will initialize tft, touch and lvgl
   init_gui();
-  setLabelCurrentScene();
+  setLabelActiveScene();
   gui_loop(); // Run the LVGL UI once before the loop takes over
 
   // setup the Inertial Measurement Unit (IMU) for motion detection. Has to be after init_gui(), otherwise I2C will not work