class mit übergebenen array Größen erstellen

[HaWe]

also dies funktioniert nicht

class tMenu {
  
  protected:    
        int16_t  MENULEN, CAPTLEN;     
        char    list[MENULEN][CAPTLEN];      
              
  
  public:      
    
     tMenu (int16_t menulen, int16_t captlen) // constructor
     {
        MENULEN = menulen;
        CAPTLEN = captlen;
       
        list = new char*[menulen];
        for(int i = 0; i < captlen; i++)
        {
          list[i] = new char[captlen];
        }
        
     }      

};

exit status 1
invalid use of non-static data member 'tMenu::MENULEN'

so auch nicht:

class tMenu {
  
  protected:    
        int16_t  MENULEN, CAPTLEN;                  
        char    **list;      
  
  public:      
      
     tMenu (int16_t menulen, int16_t captlen) // constructor
     {
        MENULEN = menulen;
        CAPTLEN = captlen;
       
        list = new char*[menulen];
        for(int i = 0; i < captlen; i++)
        {
          list[i] = new char[captlen];
        }
        
     }      
}; 

tMenu mymenu(20,10);
//...
  char test[15]="5 newline_";
  strcpy(mymenu.list[5], test);

exit status 1
'char** tMenu::list' is protected

dies funktioniert offenbar, von außen aufgerufen

class tMenu {
  
  protected:    
        int16_t  MENULEN, CAPTLEN;                  
          
  
  public:      
     char    **list;     
     tMenu (int16_t menulen, int16_t captlen) // constructor
     {
        MENULEN = menulen;
        CAPTLEN = captlen;
       
        list = new char*[menulen];
        for(int i = 0; i < captlen; i++)
        {
           list[i] = new char[captlen];
        }
        
     }      

 
     ~tMenu() // destructor
     {
       // Dynamically delete the array we allocated earlier
       delete[] list ;
     }

};
 

tMenu mymenu(20,10);

void setup(void)
{
  // Start Serial
  
  Serial.begin(115200);
  delay(2000); // wait for Serial()
  Serial.println("Serial started");
  
  char test[15]="5 newline_";
  strcpy(mymenu.list[5], test);
  Serial.println(mymenu.list[5]);
  mymenu.list[5][0]='>';
  Serial.println(mymenu.list[5]);
  //
}

- - - Aktualisiert - - -

was allerdings nicht funktioniert, ist die Benutzung der array Zellen intern,
z.B. per init cstrings reinkopieren:

class tMenu {
  
  protected:    
        int16_t  MENULEN, CAPTLEN; 
        char buf[20];                 
          
  
  public:      
     char    **list;     
     tMenu (int16_t menulen, int16_t captlen) // constructor
     {
        MENULEN = menulen;
        CAPTLEN = captlen;
       
        list = new char*[MENULEN];
        for(int i = 0; i < CAPTLEN; i++)
        {
          list[i] = new char[CAPTLEN];
        }        
     }      
     
     void init() {
        for(int i=0; i<MENULEN; i++) {
           sprintf(buf,"%d line %d", i);
           strcpy(list[i], buf);
        }
     }

 
     ~tMenu() // destructor
     {
       // Dynamically delete the array we allocated earlier
       delete[] list ;
     }

};

//
  tMenu mymenu;
  mymenu.init();

Exception (29):
epc1=0x40205d7b epc2=0x00000000 epc3=0x00000000 excvaddr=0x00000000 depc=0x00000000

ctx: cont
sp: 3fff0250 end: 3fff0550 offset: 01a0

>>>stack>>>
3fff03f0: 00000022 3ffef4fc 00000028 402025a3
3fff0400: 3ffe9d80 4010560e feefeffe feefeffe
3fff0410: feefeffe feefeffe 00000000 4000050c
3fff0420: 3fffc278 40105464 3fffc200 00000022
3fff0430: 3fff0440 feefeffe feefeffe feefeffe
3fff0440: 402040f9 00000030 0000001e ffffffff
(usw...)
<<<stack<<<

- - - Aktualisiert - - -

auch so geht es nicht:

   void init() {
        for(int i=0; i<MENULEN; i++) {
           sprintf(buf,"%d line %d", i);
           strcpy(list[i*CAPTLEN], buf);
        }
     }

wie muss man jetzt stattdessen this->init() richtig codieren?