Motor Encoder help

I am trying to code something for the turning point competition. Using a motor encoder i want to be able to press a button and have our lift extend to a specific point for easy scoring. I figured out how to make a motor rotate a certain amount and then stop, but still haven’t figured out how to map it to a button.

You need to detect the button press in this way.

  if( vexRT[Btn5D] == 1 ) {
      // start motor
      // wait for motor to reach the encoder value
      // stop motor

      // optionally, wait for button release here
      while( vexRT[Btn5D] == 1 ) {