Playing tunes

Hi All,
I was just wondering how I would set the arduino up so it could play a tune when a push button is pressed,
I have tested the toneMelody sketch and it works perfectly, How would I edit the coding to insert a pushbutton read to start the tune.

Kind regards,
Steve

if (digitalRead (pinX)==LOW){
// play tone
}

in void setup:

pinMode (pinX, INPUT_PULLUP);
// pin with internal pullup, wire switch to close to gnd when pressed

ok, Thanks for the help.
Thankyou muchly.

Steve