Interrupt on change (interrupt when the state of a pin changes)
Again this is a snippet from another chip (16F873A) but it will give you something to start with.
Code:
ON INTERRUPT GOTO MYINT
INTCON = %10010000   'PORTB.0 CHANGE

DISABLE
MYINT:
IF PORTB.0 = 1 THEN
    ' DO SOMETHING
ELSE
    'DO SOMETHING ELSE
ENDIF
INTCON.1 = 0
RESUME
ENABLE
 'THE ABOVE WILL ALSO DEBOUNCE THE SWITCH