You have the following lines:
auto charge = std::to_string(i);SimpleTextDraw(lcd_get_width() / 2, lcd_get_height() / 4 + 35, charge, WHITE_TEXT, 100, LAYER_FRONT);
In the first line the call to
std::to_string
returns (and sets
charge
equal to) a new
std::string
. In the second line the third parameter, according to the error message, is expected to be a
constant char
. So you cannot pass a string when it expects a character.