Removing Rollover state w/ Actionscript

programming flash
1

Hello.

I am trying to remove a rollover and rollout states from a button, AFTER
the button has been pressed. I want to KEEP that button in its pressed state once pressed. How might I do this? Thanks for anyone’s thoughts.

Here is my code:

stop();

bttnEv.onRollOver = function() {
overOne.gotoAndPlay(2);
}

bttnEv.onRollOut = function() {
overOne.gotoAndPlay(5);
}

bttnEv.onPress = function() {
overOne.gotoAndStop(9);
delete bttnEv.onRollOver;
delete bttnEv.onRollOut;
}