Is there any way to override the type of a property? As an example, if I have written a list class:

type
     tList = class (tObject)
         private
             t_current : tObject;
             t_items : array of tObject;
         public
             property Current : tObject read t_current write t_current;
     end;

(this example is clearly not complete) and I want to create a descendant type that uses a different object, without worrying about typecasting. Is there a way to override Current? I tried generics, but using such renders me unable to access the list items' properties, making it impossible to sort the list.

"Timothy Groves" wrote

Is there any way to override the type of a property? As an example, if I

have written a list class:

type that uses a different object, without worrying about typecasting. Is there a way to override Current? I tried generics, but using such renders me unable to access the list items' properties, making it impossible to sort the list.

Normally you simply declare the property anew in your child class. Look at TObjectList from unit contnrs for an example.
In your specific case you'll need a Getter-method that returns "TWhatEverSubclass(inherited Current)".

What exactly is your problem with using generics?

Regards
Sven

Thanks, that helped me figure it out.

What exactly is your problem with using generics?

I can't access properties of whatever data type I used to specialize. So it's difficult to write a class that contains a list, that allows me to sort that list.

"Timothy Groves" wrote

> What exactly is your problem with using generics? I can't access properties of whatever data type I used to specialize. So

it's difficult to write a class that contains a list, that allows me to sort that list.

Do you have an example? Maybe you're misunderstanding something. You can also take a look at TFPGList in unit fgl or the stl units in packages/fcl-stl.

Regards,
Sven