Add menu items with function?

[mscosti]

Hello, I was curious if it is possible to create menu items programmatically by using a function. One section of my menu I want to be the names of files on an SD card (which will be limited), which I only know at runtime. This is something that would only happen once in the program's lifetime.

[Jomelo]

Hi,
at the moment it is not possible because some items are saved in flash (PROGMEM), not in ram. I check tomorrow, if i can create a dynamic menu function, thats locks like a tree.

[Jomelo]

In next beta i add an example for dynamic lists with scrollbars. The current code is not perfektly commented. It can be that there are variables without a function. I have no time to optimaze the code.
I hope the code can help.

DISP function code looks like this.

// this needs some bytes in ram
#define MAX_FILES_IN_LIST 20

uint8_t scroll_row;
uint8_t cursor_real_pos;
uint8_t current_max_list_count;
uint8_t cursor_position_cur;
char file_name_buffer[20];
static char filelist[MAX_FILES_IN_LIST][20];


// *********************************************************************
void LCDML_DISP_setup(LCDML_FUNC_list_files)
// *********************************************************************
{
  // set max file counter
  current_max_list_count = 0;
  // set current cursor position
  cursor_position_cur = 0;
  // 
  scroll_row = 0;
  cursor_real_pos = 0;


  // read sd card files here 
  uint8_t n=0;
  // for example, here with a for loop
  for(uint8_t i = 0; i<10; i++) {
    if(i < MAX_FILES_IN_LIST) { 
      memcpy(filelist[i], "File  .txt", 10);      
      filelist[i][5] = i+48;
      current_max_list_count++; 
    }
  } 
}

void LCDML_DISP_loop(LCDML_FUNC_list_files) 
{
  // loop function, can be run in a loop when LCDML_DISP_triggerMenu(xx) is set
  // the quit button works in every DISP function without any checks; it starts the loop_end function


  uint8_t n_max             = (current_max_list_count >= _LCDML_DISP_rows) ? _LCDML_DISP_rows : (current_max_list_count);;
  uint8_t scrollbar_min     = 0;
  uint8_t scrollbar_max     = current_max_list_count;
  //uint8_t scrollbar_cur_pos = cursor_position_cur;
  uint8_t scroll_pos        = ((1.*n_max * _LCDML_DISP_rows) / (scrollbar_max - 1) * cursor_position_cur);



  // clear display
  // ================
  lcd.clear();

  // display content
  // ==================
  for (uint8_t n = scroll_row; n < (scroll_row+_LCDML_DISP_rows); n++)
  {   
    // set cursor
    lcd.setCursor(1, n-scroll_row);
    // set content
    lcd.print(filelist[n]);
  }

  // set cursor and scrollbar
  // =============================
  for (uint8_t n = scroll_row; n <(scroll_row+_LCDML_DISP_rows); n++)
  {
      lcd.setCursor(0, n-scroll_row);

    // set cursor
    // =====================
    if (n == cursor_position_cur) {
      lcd.write(_LCDML_DISP_cfg_cursor);
      cursor_real_pos = n-scroll_row;
    } else {
      lcd.write(' ');
    }    

    // display scrollbar
    // ==============================
    // delete or reset scrollbar
    if (scrollbar_max > n_max) {
      lcd.setCursor((_LCDML_DISP_cols - 1), n-scroll_row);
      lcd.write((uint8_t)0);
    }
    else {
      lcd.setCursor((_LCDML_DISP_cols - 1), n-scroll_row);
      lcd.print(' ');
    }

    // set scrollbar
    if (scrollbar_max > n_max) {
      //set scroll position
      if (cursor_position_cur == scrollbar_min) {
        // min pos
        lcd.setCursor((_LCDML_DISP_cols - 1), 0);
        lcd.write((uint8_t)1);
      } else if (cursor_position_cur == (scrollbar_max - 1)) {
        // max pos
        lcd.setCursor((_LCDML_DISP_cols - 1), (n_max - 1));
        lcd.write((uint8_t)4);
      } else {
        // between
        lcd.setCursor((_LCDML_DISP_cols - 1), scroll_pos / n_max);
        lcd.write((uint8_t)(scroll_pos % n_max) + 1);
      }
    }


  }



  // control
  // =====================================
  if(LCDML_BUTTON_checkUp()) {
    LCDML_BUTTON_resetAll();
    // scroll up   
    if(cursor_position_cur > 0) {
      cursor_position_cur--;
      if(cursor_real_pos == 0) {
        scroll_row--;    
      }      
    }
    // update content above or remove this line and copy button checks on top of this function
    LCDML_BACK_start(LCDML_BACKEND_menu);    
  }


  if(LCDML_BUTTON_checkDown()) {
    LCDML_BUTTON_resetAll();   
    // scroll down
    if(cursor_position_cur < (current_max_list_count-1)) {
      cursor_position_cur++;
      if(cursor_position_cur > (_LCDML_DISP_rows-1)) {
        scroll_row++; 
      } 
    }
    // update content above or remove this line and copy button checks on top of this function
    LCDML_BACK_start(LCDML_BACKEND_menu);             
  }


  if(LCDML_BUTTON_checkEnter()) {
    LCDML_BUTTON_resetAll();   
    // save selected file (serial.print)
    LCDML_DISP_funcend();
    // output of current line
    Serial.println(filelist[cursor_position_cur]);  
  }  
}

void LCDML_DISP_loop_end(LCDML_FUNC_list_files)
{
  // this functions is ever called when a DISP function is quit
  // you can here reset some global vars or do nothing 

  // Display selected file name

}