I don't know if it really helps anyone, but I was playing with this library (to replace my home-grown mess) and I took the lcd_nav example and modified it to use an OLED display and a rotary encoder for input.
Since I didn't think about using a long press of the encoder for the "back" function, I simply added an extra menu item (in each submenu) with the text "back" and a callback that does a back() call (looks like I should have used a BackMenuItem instead?)
(Regarding the "back" function, one thing I wanted to do was reset the submenu when it was re-entered so the user starts at the first menu selection, not the last. To do this I needed to call reset() for Menu and not MenuSystem, so I moved reset() from protected to public for the Menu class. Not sure if this is something anyone else would want though)
I wrote this on a Teensy 3.2 (so I use the PJRC Encoder library) using a el-cheapo SH1106 OLED display on eBay (which is why I ended up using mfGFX and not the stock Adafruit GFX library - Tomash's SH1106 library seems to depend upon mfGFX) and a rotary encoder from Sparkfun.
If you have an SSD1306 display you should be able to use the stock Adafruit libraries instead.
Since I'm using oddball hardware I'm just going to post the example here
/*
* oled_nav.ino - Example code using the menu system library
*
* This example shows using the menu system with a el cheepo
* SH1106 OLED display from eBay and a Sparkfun rotary encoder
*
* Hardware used is:
*
* - Teensy 3.2 (https://www.pjrc.com/store/teensy32.html)
* - Sparkfun Rotary Encoder (https://www.sparkfun.com/products/10982)
* - Cheap eBay SH1106 OLED Display (Adafruit's SSD1306 should also work)
*
* Software used is:
*
* - Adafruit mfGFX Graphics Library (https://forums.adafruit.com/viewtopic.php?f=47&t=61388)
* - SH1106 display library (see http://tomashg.com/?p=1263)
* - Teensy Encoder Library (https://www.pjrc.com/teensy/td_libs_Encoder.html)
*
* Copyright (c) 2016 arduino-menusystem
* Licensed under the MIT license (see LICENSE)
*/
#include <Arduino.h>
#include <MenuSystem.h>
// Need these libraries for the OLED and Rotary Encoder
#include <SPI.h>
#include <Wire.h>
#include <Encoder.h>
#include <Adafruit_mfGFX.h>
#include <Adafruit_SH1106.h>
const byte ENC_LEFT_PIN = 24;
const byte ENC_RIGHT_PIN = 25;
const byte PUSH_BUTTON_PIN = 26;
const byte OLED_RESET = 33;
Encoder myEnc(ENC_LEFT_PIN, ENC_RIGHT_PIN);
Adafruit_SH1106 lcd(-1);
//Adafruit_SSD1306 lcd(OLED_RESET);
// renderer
class MyRenderer : public MenuComponentRenderer {
public:
virtual void render(Menu const& menu) const {
lcd.clearDisplay();
lcd.setTextColor(WHITE);
lcd.setCursor(0,0);
lcd.print(menu.get_name());
lcd.setCursor(0,20);
menu.get_current_component()->render(*this);
lcd.display();
}
virtual void render_menu_item(MenuItem const& menu_item) const {
lcd.print(menu_item.get_name());
lcd.display();
}
virtual void render_back_menu_item(BackMenuItem const& menu_item) const {
lcd.print(menu_item.get_name());
lcd.display();
}
virtual void render_numeric_menu_item(NumericMenuItem const& menu_item) const {
lcd.print(menu_item.get_name());
lcd.display();
}
virtual void render_menu(Menu const& menu) const {
lcd.print(menu.get_name());
lcd.display();
}
};
MyRenderer my_renderer;
// Forward declarations
void on_item1_selected(MenuItem* p_menu_item);
void on_item2_selected(MenuItem* p_menu_item);
void on_item3_selected(MenuItem* p_menu_item);
void on_back_selected(MenuItem* p_menu_item);
int readEncoder(void);
// Menu variables
MenuSystem ms(my_renderer);
MenuItem mm_mi1("Level 1 - Item 1 (Item)", &on_item1_selected);
MenuItem mm_mi2("Level 1 - Item 2 (Item)", &on_item2_selected);
Menu mu1("Level 1 - Item 3 (Menu)");
MenuItem mu1_mi1("Level 2 - Item 1 (Item)", &on_item3_selected);
MenuItem mu1_mi2("Level 2 - Back", &on_back_selected);
// Helper function(s) for OLED display
// Display (or erase) text on the OLED
void showIt(const char * text, boolean erase) {
if (erase)
lcd.setTextColor(BLACK);
else
lcd.setTextColor(WHITE);
lcd.setCursor(0,30);
lcd.print(text);
lcd.display();
}
// Main display routine for selection handling
void showSelected(const char * text) {
showIt(text, false); // Show the text
delay(1500); // Wait for a moment
showIt(text, true); // Erase text
}
// Menu callback functions
void on_item1_selected(MenuItem* p_menu_item) {
showSelected("Item1 Selected ");
}
void on_item2_selected(MenuItem* p_menu_item) {
showSelected("Item2 Selected ");
}
void on_item3_selected(MenuItem* p_menu_item) {
showSelected("Item3 Selected ");
}
// This callback should be used any time a "back" selection is needed
void on_back_selected(MenuItem* p_menu_item) {
ms.back();
}
// Get input from the Rotary Encoder
void rotaryHandler() {
short command = readEncoder();
switch (command) {
case -1: // LEFT
ms.prev();
ms.display();
break;
case 1: // RIGHT
ms.next();
ms.display();
break;
case 0: // SELECT
ms.select();
ms.display();
delay(100); // Crude debounce attempt
break;
}
}
// Read the Rotary encoder and wait for a button press or movement
//
// Based on code from
//(https://simelectronics.wordpress.com/2012/11/10/using-encoders-with-x-plane/)
int readEncoder(void) {
while (1) {
// Has a button been pressed?
if (digitalRead(PUSH_BUTTON_PIN) == HIGH) {
// Yes. Make sure it's been released
while (digitalRead(PUSH_BUTTON_PIN) == HIGH) {}
return 0;
} else {
// divide by 4 to find how many 'clicks' the encoder's gone through
short myEncDiff = myEnc.read() / 4;
if (myEncDiff) {
// only done when we've reached a detent!
myEnc.write(0);
return myEncDiff;
}
}
}
return 0; // Just to keep the compiler happy
}
// Standard arduino functions
void setup() {
pinMode(PUSH_BUTTON_PIN, INPUT);
lcd.begin(SH1106_SWITCHCAPVCC, 0x3C); // Default I2C Address
//lcd.begin(SSD1306_SWITCHCAPVCC, 0x3D); // Use I2C addr 0x3D
lcd.clearDisplay();
lcd.drawPixel(0,0,BLACK); // Remove stray pixel on screen??
lcd.setTextColor(WHITE);
lcd.display();
ms.get_root_menu().add_item(&mm_mi1);
ms.get_root_menu().add_item(&mm_mi2);
ms.get_root_menu().add_menu(&mu1);
mu1.add_item(&mu1_mi1);
mu1.add_item(&mu1_mi2);
ms.display();
}
void loop() {
rotaryHandler();
}
The example will print the menu name at the top line of the display (root menu is simply blank), then the menu item below that. Selecting an item will cause the text "Selected" to appear below the menu item for 1.5 seconds.
Strictly FWIW (Your mileage may vary, objects in mirror are closer than they appear, do not taunt happy fun ball)
Regards,
Brad
KF7FER