Make a menu on the display, control buttons on Arduino.

In order to make a button-driven menu for arduino with output to the display, we need 2 libraries.

1. LiquidCrystal_I2C
2. Wire

The video shows an example of how to make a menu in which you can select one of the items and click on the button to start some action.
eg:
Switch on / off the relay.
This is a great start for many projects.
I wanted to thank the author of this code (Video author).

Any number of items can be created in this menu. The code is projected onto the LiquidCrystal 1602 display. Arduino UNO

The sketch can be downloaded below.

#include <Wire.h>
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);

int upButton = 10;
int downButton = 11;
int selectButton = 12;
int menu = 1;

void setup() {
  lcd.begin();
  lcd.backlight();
  pinMode(upButton, INPUT_PULLUP);
  pinMode(downButton, INPUT_PULLUP);
  pinMode(selectButton, INPUT_PULLUP);
  updateMenu();
}

void loop() {
  if (!digitalRead(downButton)){
    menu++;
    updateMenu();
    delay(100);
    while (!digitalRead(downButton));
  }
  if (!digitalRead(upButton)){
    menu--;
    updateMenu();
    delay(100);
    while(!digitalRead(upButton));
  }
  if (!digitalRead(selectButton)){
    executeAction();
    updateMenu();
    delay(100);
    while (!digitalRead(selectButton));
  }
}

void updateMenu() {
  switch (menu) {
    case 0:
      menu = 1;
      break;
    case 1:
      lcd.clear();
      lcd.print(">MenuItem1");
      lcd.setCursor(0, 1);
      lcd.print(" MenuItem2");
      break;
    case 2:
      lcd.clear();
      lcd.print(" MenuItem1");
      lcd.setCursor(0, 1);
      lcd.print(">MenuItem2");
      break;
    case 3:
      lcd.clear();
      lcd.print(">MenuItem3");
      lcd.setCursor(0, 1);
      lcd.print(" MenuItem4");
      break;
    case 4:
      lcd.clear();
      lcd.print(" MenuItem3");
      lcd.setCursor(0, 1);
      lcd.print(">MenuItem4");
      break;
    case 5:
      menu = 4;
      break;
  }
}

void executeAction() {
  switch (menu) {
    case 1:
      action1();
      break;
    case 2:
      action2();
      break;
    case 3:
      action3();
      break;
    case 4:
      action4();
      break;
  }
}

void action1() {
  lcd.clear();
  lcd.print(">Executing #1");
  delay(1500);
}
void action2() {
  lcd.clear();
  lcd.print(">Executing #2");
  delay(1500);
}
void action3() {
  lcd.clear();
  lcd.print(">Executing #3");
  delay(1500);
}
void action4() {
  lcd.clear();
  lcd.print(">Executing #4");
  delay(1500);
}