kanel:
I will try to use them but the program does not compile properly.
For example I use this function: "char getKey () -Returns the key pressed That Is, if any. This function is non-blocking"
in this way:char key = getKey ();
and so does not compile .. while the same function used in their example becomes:
char key = keypad.getKey ();
this is not the same thing. is not it? and why?
If you don't know the difference, you need to read basics of object oriented programming. There's endless tutorials on that topic. There is no point explaining the code to you before you understand the basic.