From 10b9632bed6ef78ef2460b71526111d89b4113c2 Mon Sep 17 00:00:00 2001
From: Scott Lahteine <github@thinkyhead.com>
Date: Thu, 4 Apr 2019 02:29:44 -0500
Subject: [PATCH] Fix menu history item selection

---
 Marlin/src/lcd/menu/menu.cpp | 23 ++++++++++-------------
 Marlin/src/lcd/menu/menu.h   |  4 ++--
 Marlin/src/lcd/ultralcd.h    |  2 +-
 3 files changed, 13 insertions(+), 16 deletions(-)

diff --git a/Marlin/src/lcd/menu/menu.cpp b/Marlin/src/lcd/menu/menu.cpp
index 77b2e18fa7..0365df2356 100644
--- a/Marlin/src/lcd/menu/menu.cpp
+++ b/Marlin/src/lcd/menu/menu.cpp
@@ -54,10 +54,12 @@
 ////////////////////////////////////////////
 
 // Menu Navigation
-int8_t encoderTopLine;
+int8_t encoderTopLine, encoderLine, screen_items;
+
 typedef struct {
   screenFunc_t menu_function;
   uint32_t encoder_position;
+  uint8_t top_line, items;
 } menuPosition;
 menuPosition screen_history[6];
 uint8_t screen_history_depth = 0;
@@ -80,20 +82,14 @@ bool no_reentry = false;
 void MarlinUI::return_to_status() { goto_screen(status_screen); }
 
 void MarlinUI::save_previous_screen() {
-  if (screen_history_depth < COUNT(screen_history)) {
-    screen_history[screen_history_depth].menu_function = currentScreen;
-    screen_history[screen_history_depth].encoder_position = encoderPosition;
-    ++screen_history_depth;
-  }
+  if (screen_history_depth < COUNT(screen_history))
+    screen_history[screen_history_depth++] = { currentScreen, encoderPosition, encoderTopLine, screen_items };
 }
 
 void MarlinUI::goto_previous_screen() {
   if (screen_history_depth > 0) {
-    --screen_history_depth;
-    goto_screen(
-      screen_history[screen_history_depth].menu_function,
-      screen_history[screen_history_depth].encoder_position
-    );
+    menuPosition &sh = screen_history[--screen_history_depth];
+    goto_screen(sh.menu_function, sh.encoder_position, sh.top_line, sh.items);
   }
   else
     return_to_status();
@@ -197,7 +193,7 @@ bool printer_busy() {
 /**
  * General function to go directly to a screen
  */
-void MarlinUI::goto_screen(screenFunc_t screen, const uint32_t encoder/*=0*/) {
+void MarlinUI::goto_screen(screenFunc_t screen, const uint32_t encoder/*=0*/, const uint8_t top/*=0*/, const uint8_t items/*=0*/) {
   if (currentScreen != screen) {
 
     #if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
@@ -246,6 +242,8 @@ void MarlinUI::goto_screen(screenFunc_t screen, const uint32_t encoder/*=0*/) {
 
     currentScreen = screen;
     encoderPosition = encoder;
+    encoderTopLine = top;
+    screen_items = items;
     if (screen == status_screen) {
       defer_status_screen(false);
       #if ENABLED(AUTO_BED_LEVELING_UBL)
@@ -314,7 +312,6 @@ void MarlinUI::synchronize(PGM_P const msg/*=NULL*/) {
  *   _thisItemNr is the index of each MENU_ITEM or STATIC_ITEM
  *   screen_items is the total number of items in the menu (after one call)
  */
-int8_t encoderLine, screen_items;
 void scroll_screen(const uint8_t limit, const bool is_menu) {
   ui.encoder_direction_menus();
   ENCODER_RATE_MULTIPLY(false);
diff --git a/Marlin/src/lcd/menu/menu.h b/Marlin/src/lcd/menu/menu.h
index c17f116775..e695a02433 100644
--- a/Marlin/src/lcd/menu/menu.h
+++ b/Marlin/src/lcd/menu/menu.h
@@ -309,8 +309,8 @@ class MenuItem_bool {
 
 #define MENU_BACK(LABEL) MENU_ITEM(back, LABEL)
 #define MENU_ITEM_DUMMY() do { _thisItemNr++; }while(0)
-#define MENU_ITEM_P(TYPE, PLABEL, ...)                       _MENU_ITEM_VARIANT_P(TYPE,              , false, PLABEL,                   ## __VA_ARGS__)
-#define MENU_ITEM(TYPE, LABEL, ...)                          _MENU_ITEM_VARIANT_P(TYPE,              , false, PSTR(LABEL),              ## __VA_ARGS__)
+#define MENU_ITEM_P(TYPE, PLABEL, ...)                       _MENU_ITEM_VARIANT_P(TYPE,      , false, PLABEL,                   ## __VA_ARGS__)
+#define MENU_ITEM(TYPE, LABEL, ...)                          _MENU_ITEM_VARIANT_P(TYPE,      , false, PSTR(LABEL),              ## __VA_ARGS__)
 #define MENU_ITEM_EDIT(TYPE, LABEL, ...)                     _MENU_ITEM_VARIANT_P(TYPE, _edit, false, PSTR(LABEL), PSTR(LABEL), ## __VA_ARGS__)
 #define MENU_ITEM_EDIT_CALLBACK(TYPE, LABEL, ...)            _MENU_ITEM_VARIANT_P(TYPE, _edit, false, PSTR(LABEL), PSTR(LABEL), ## __VA_ARGS__)
 #define MENU_MULTIPLIER_ITEM_EDIT(TYPE, LABEL, ...)          _MENU_ITEM_VARIANT_P(TYPE, _edit,  true, PSTR(LABEL), PSTR(LABEL), ## __VA_ARGS__)
diff --git a/Marlin/src/lcd/ultralcd.h b/Marlin/src/lcd/ultralcd.h
index f8899f1175..df36256ba1 100644
--- a/Marlin/src/lcd/ultralcd.h
+++ b/Marlin/src/lcd/ultralcd.h
@@ -419,7 +419,7 @@ public:
     static void synchronize(PGM_P const msg=NULL);
 
     static screenFunc_t currentScreen;
-    static void goto_screen(const screenFunc_t screen, const uint32_t encoder=0);
+    static void goto_screen(const screenFunc_t screen, const uint32_t encoder=0, const uint8_t top=0, const uint8_t items=0);
     static void save_previous_screen();
     static void goto_previous_screen();
     static void return_to_status();