This is a simple funcion that get input from a keypad (like we used to do on old phones before the smartphone's era).
It depends on:
- Keypad library for input
- TFT_eSPI library for screen output
Add t9.h to your code and you can get the String by passing the two objects to the function:
// start the t9 loop and get the string from the user input
String result = t9(&tft, &keypad);
to write on the T9 keyboard, use 1-0 keys. Use "D" key to move cursor forward, "C" button to move backward, "A" button to exit loop and get the resulting string.
Example is on main.cpp.
NB: you can find an alternative version using PCF8574 and I2CKeyPad library on the PCF8574 branch.
