Improve LCD leveling edits

Marlin/src/lcd/ultralcd.cpp

@@ -1906,11 +1906,12 @@ void kill_screen(const char* lcd_msg) {
       enqueue_and_echo_commands_P(PSTR("G28"));
     }
 
-    static bool _level_state;
-    void _lcd_toggle_bed_leveling() { set_bed_leveling_enabled(_level_state); }
+    static bool new_level_state;
+    void _lcd_toggle_bed_leveling() { set_bed_leveling_enabled(new_level_state); }
 
     #if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
-      void _lcd_set_z_fade_height() { set_z_fade_height(planner.z_fade_height); }
+      static float new_z_fade_height;
+      void _lcd_set_z_fade_height() { set_z_fade_height(new_z_fade_height); }
     #endif
 
     /**
@@ -1934,13 +1935,11 @@ void kill_screen(const char* lcd_msg) {
       if (!(axis_known_position[X_AXIS] && axis_known_position[Y_AXIS] && axis_known_position[Z_AXIS]))
         MENU_ITEM(gcode, MSG_AUTO_HOME, PSTR("G28"));
       else if (leveling_is_valid()) {
-        _level_state = planner.leveling_active;
-        MENU_ITEM_EDIT_CALLBACK(bool, MSG_BED_LEVELING, &_level_state, _lcd_toggle_bed_leveling);
+        MENU_ITEM_EDIT_CALLBACK(bool, MSG_BED_LEVELING, &new_level_state, _lcd_toggle_bed_leveling);
       }
 
       #if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
-        //set_z_fade_height(planner.z_fade_height);
-        MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(float62, MSG_Z_FADE_HEIGHT, &planner.z_fade_height, 0.0, 100.0, _lcd_set_z_fade_height);
+        MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(float62, MSG_Z_FADE_HEIGHT, &new_z_fade_height, 0.0, 100.0, _lcd_set_z_fade_height);
       #endif
 
       //
@@ -1971,6 +1970,16 @@ void kill_screen(const char* lcd_msg) {
       END_MENU();
     }
 
+    void _lcd_goto_bed_leveling() {
+      currentScreen = lcd_bed_leveling;
+      #if ENABLED(LCD_BED_LEVELING)
+        new_level_state = planner.leveling_active;
+      #endif
+      #if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
+        new_z_fade_height = planner.z_fade_height;
+      #endif
+    }
+
   #elif ENABLED(AUTO_BED_LEVELING_UBL)
 
     void _lcd_ubl_level_bed();
@@ -2541,7 +2550,13 @@ void kill_screen(const char* lcd_msg) {
       #if ENABLED(PROBE_MANUALLY)
         if (!g29_in_progress)
       #endif
-      MENU_ITEM(submenu, MSG_BED_LEVELING, lcd_bed_leveling);
+          MENU_ITEM(submenu, MSG_BED_LEVELING,
+            #if ENABLED(ENABLE_LEVELING_FADE_HEIGHT)
+              _lcd_goto_bed_leveling
+            #else
+              lcd_bed_leveling
+            #endif
+          );
     #else
       #if PLANNER_LEVELING
         MENU_ITEM(gcode, MSG_BED_LEVELING, PSTR("G28\nG29"));