Hello!
I have made a menu using switch case so when the user presses the select button a function is carried out.
Issue:
One of the functions contains another switch case that also uses buttons but when I click the buttons again only the menu is controlled and not the function i.e. it will load the function and the first case but when a button is clicked nothing happens.
What I want to happen:
I want the buttons to stop controlling the menu and control the switch in the other function. The buttons should only control the menu when the menu function is called (and the same for the other respective functions).
I'm not sure how to tackle this and don't know what the problem is.
n.b. please do not suggest any additional libraries other than the ones i have used, also the function works fine by itself when outside the menu so I know it works. I am also new to programming in C and using the arduino.
n.b. I have also tried using a nested switch case to no avail 
(although I may have been going about this in a bad way). I am open to using if statements (or anything else appropriate) as well (as a last resort) however I would much prefer to use switch cases.
I greatly appreciate any help as I am at my wits end 
#include <Wire.h>
#include <Adafruit_RGBLCDShield.h>
#include <utility/Adafruit_MCP23017.h>
#include <EEPROM.h>
Adafruit_RGBLCDShield lcd = Adafruit_RGBLCDShield();
//variables to decide which buttons are being used when
bool choosing;
bool playing;
//variables to select the users choices, 3 and 2 and the starting numbers displayed
int size_S=4;
int size_M=2;
uint8_t choice=1;
uint8_t oldButtons=0;
char buffer [12];
//function displaying the menu options
void SelectDisplay(int size_S, int size_M){
lcd.setCursor(0,0);
sprintf(buffer, "S:%02d M:%02d", size_S, size_M);
lcd.print(buffer);
lcd.setCursor (0,1);
lcd.print((choice==1?"Choose S":"Choose M"));
}
//variables to store user's choice
int choice_S;
int choice_M;
//!!THIS IS THE FUNCTION THAT DOESN'T WORK INSIDE THE MENU
//function for user to select options S and M
int Select(int choice_S, int choice_M){
uint8_t buttons, changes;
buttons = lcd.readButtons ();
changes = oldButtons & (~buttons);
if (playing==true){
//calling the menu disply function
SelectDisplay (size_S,size_M);
switch (choice){
case 1: //case S
if (changes & BUTTON_UP){
size_S = (size_S == 10 ? 4:size_S+1);
}else if (changes & BUTTON_DOWN){
size_S = (size_S == 4 ? 10:size_S-1);
}else if (changes & BUTTON_RIGHT){
choice= 2;
}
break;
case 2: //case M
if (changes & BUTTON_UP){
size_M = (size_M == 4 ? 2:size_M+1);
}else if (changes & BUTTON_DOWN){
size_M = (size_M == 2 ? 4:size_M-1);
}else if (changes & BUTTON_LEFT){
choice = 1;
}
break;
}
if (changes & BUTTON_SELECT){
choice_S=size_S;
choice_M=size_M;
}
}
oldButtons=buttons;
}
//variable to change the menu page and options
int menu=1;
//function displaying what the menu options
void displayMenu(){
switch(menu){
case 0:
menu=1;
break;
case 1:
lcd.clear();
lcd.setCursor(0,0);
lcd.print(">Play");
lcd.setCursor(0,1);
lcd.print(" Characters");
break;
case 2:
lcd.clear();
lcd.setCursor(0,0);
lcd.print(" Play");
lcd.setCursor(0,1);
lcd.print(">Characters");
break;
case 3:
break;
//etc..
}
}
//function for carrying out the user's menu selection
void menuAction (){
switch (menu){
case 1://play
Select(choice_S, choice_M); //!!HERE IS WHERE THE FUNCTION I WANT TO WORK IS CALLED
break;
case 2:
break;
case 3:
break;
//etc..
}
}
//function for navigating the menu
void mainMenu(){
int navigate = lcd.readButtons ();
if (playing==true){
choosing=false;
}else{
choosing=true;
}
if(choosing==true){
//if statement to navigate the menu
if (BUTTON_DOWN & navigate){
menu++;
displayMenu();
delay(200);
}
if (BUTTON_UP & navigate){
menu--;
displayMenu();
delay(200);
}
if (BUTTON_SELECT & navigate){
playing=true;
menuAction();
delay(200);
}
}
}
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
lcd.begin(16,2);
displayMenu();
choice=1;
choosing=true;
}
void loop() {
// put your main code here, to run repeatedly:
mainMenu();
}