Easy menu drawer to use with 16x2 character LCD for AVR. Note: This CharMenu by default uses lcd_lib.h from Scienceprog.com (GPL license). but using other library is possible by editing these wrapper function
void cm_LcdInit(void);
void cm_LcdClear(void);
void cm_LcdDelete(uint8_t xawal, uint8_t xakhir, uint8_t _Y);
void cm_LcdString(uint8_t* string, uint8_t len);
void cm_LcdGotoXY(uint8_t x, uint8_t y);
16x2 Char LCD is popular among embedded system, widely used in system debugging even for user display.
Building menu and its navigation for this limited characters LCD with good User-Experience is a bit hard. Therefore CharMenu propose the use of four buttons: [Enter] [Back] [Scroll Left] [Scroll Right] to navigate through the options displayed in the LCD.
The two scroll button will navigate the menu to the left/right which is sibling menu. Enter button will either enter the submenu (children menu) or execute some callback function to do. Back button will navigate the menu to the parent's menu
For an example, there are these menu:
[MainMenu]
[FoodMenu]------------------[DrinkMenu]
[Pizza]---[Kebab] [CocaCola]--[Pepsi]--[BigCola]
Inside the MainMenu there are two menus, to pick Food or Drink. Inside FoodMenu there are menus to pick wether to run pizza or kebab. On the image above, the Kebab menu is displayed, thus the cursor is to navigate between Kebab and Pizza. Hitting Enter will execute the function callback which is binded to the kebab menu. Hitting prev/scroll left button will navigate the menu to Pizza menu, Hitting next/scroll right menu will get the cursor to the next menu which --as kebab is already the right most menu-- will jump the cursor to the left most menu: Pizza. Back button will return the menu to its parent menu, the menu to pick either FoodMenu or DrinkMenu.
See example