Hi, Bernard. If I understand you correctly then it sounds like everything is working the way it is supposed to. A protected property isn't available anywhere outside of its class. Therefore a method in the class can modify the property, but no object that inherits from the class can. You would need to send a message to a class method that say's I want to set a value for oldtop. The method in the class would be responsible for doing it. (i.e. the code to set the property would be in the class.)

HTH


>I am confused about custom properties of classes.
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