Fix menu reset bug

`select` can no longer be used to reset the menu. Instead, a separate
`reset` function is provided.

Fixes #14

Author: jonblack

MenuSystem.cpp

@@ -92,6 +92,14 @@ MenuComponent* Menu::select()
     return this;
 }
 
+void Menu::reset()
+{
+    for (int i = 0; i < _num_menu_components; ++i)
+        _menu_components[i]->reset();
+    _cur_menu_component_num = 0;
+    _p_sel_menu_component = _menu_components[0];
+}
+
 void Menu::add_item(MenuItem* pItem, void (*on_select)(MenuItem*))
 {
     // Resize menu component list, keeping existing items.
@@ -187,6 +195,11 @@ MenuComponent* MenuItem::select()
     return 0;
 }
 
+void MenuItem::reset()
+{
+    // Do nothing.
+}
+
 // *********************************************************
 // MenuSystem
 // *********************************************************
@@ -207,22 +220,18 @@ boolean MenuSystem::prev(boolean loop)
     return _p_curr_menu->prev(loop);
 }
 
-void MenuSystem::select(boolean return_to_root)
+void MenuSystem::reset()
+{
+    _p_curr_menu = _p_root_menu;
+    _p_root_menu->reset();
+}
+
+void MenuSystem::select()
 {
     MenuComponent* pComponent = _p_curr_menu->activate();
 
     if (pComponent != NULL)
-    {
         _p_curr_menu = (Menu*) pComponent;
-    }
-    else
-    {
-        // A menu item was selected.
-        // If return_to_root is true, reset the menu ready for when it's used
-        // again; otherwise, the current menu is remembered.
-        if (return_to_root)
-            _p_curr_menu = _p_root_menu;
-    }
 }
 
 boolean MenuSystem::back()

MenuSystem.h

@@ -21,6 +21,7 @@ class MenuComponent
     const char* get_name() const;
 
     virtual MenuComponent* select() = 0;
+    virtual void reset() = 0;
 
 protected:
     const char* _name;
@@ -35,6 +36,7 @@ class MenuItem : public MenuComponent
     void set_select_function(void (*on_select)(MenuItem*));
 
     virtual MenuComponent* select();
+    virtual void reset();
 
 private:
     void (*_on_select)(MenuItem*);
@@ -50,6 +52,7 @@ class Menu : public MenuComponent
     boolean prev(boolean loop=false);
     MenuComponent* activate();
     virtual MenuComponent* select();
+    virtual void reset();
 
     void add_item(MenuItem* pItem, void (*on_select)(MenuItem*));
     Menu const* add_menu(Menu* pMenu);
@@ -79,7 +82,8 @@ class MenuSystem
 
     boolean next(boolean loop=false);
     boolean prev(boolean loop=false);
-    void select(boolean return_to_root=true);
+    void reset();
+    void select();
     boolean back();
 
     void set_root_menu(Menu* p_root_menu);

examples/current_item/current_item.ino

@@ -16,19 +16,17 @@ MenuItem mm_mi1("Level 1 - Item 1 (Item)");
 MenuItem mm_mi2("Level 1 - Item 2 (Item)");
 Menu mu1("Level 1 - Item 3 (Menu)");
 MenuItem mu1_mi1("Level 2 - Item 1 (Item)");
-
-// Example variables
-bool bRanCallback = false;
-bool bForward = true;
+MenuItem mu1_mi2("Level 2 - Item 2 (Item)");
 
 // Menu callback function
 // In this example all menu items use the same callback.
 
+bool bRanCallback = false;
+
 void on_item1_selected(MenuItem* p_menu_item)
 {
   Serial.println("Item1 Selected");
   bRanCallback = true;
-  bForward = true;
 }
 
 void on_item2_selected(MenuItem* p_menu_item)
@@ -41,42 +39,40 @@ void on_item3_selected(MenuItem* p_menu_item)
 {
   Serial.println("Item3 Selected");
   bRanCallback = true;
-  bForward = false;
+}
+
+void on_item4_selected(MenuItem* p_menu_item)
+{
+  Serial.println("Item4 Selected");
+  bRanCallback = false;
+  ms.reset();
 }
 
 // Standard arduino functions
 
 void setup()
 {
   Serial.begin(9600);
-  
+
   // Menu setup
   mm.add_item(&mm_mi1, &on_item1_selected);
   mm.add_item(&mm_mi2, &on_item2_selected);
   mm.add_menu(&mu1);
   mu1.add_item(&mu1_mi1, &on_item3_selected);
+  mu1.add_item(&mu1_mi2, &on_item4_selected);
   ms.set_root_menu(&mm);
 }
 
 void loop()
 {
-  Serial.println("");
-  
-  // Display the menu
   Serial.println(ms.get_current_menu()->get_selected()->get_name());
-  
-  // Simulate using the menu by walking over the entire structure.
   ms.select();
-  
   if (bRanCallback)
   {
-    if (bForward)
       ms.next();
-    else
-      ms.prev();
-    bRanCallback = false;
+      bRanCallback = false;
   }
-  
+
   // Wait for two seconds so the output is viewable
   delay(2000);
 }