DropDown component DisabledProperty as a bool

To disable certain items in the DropDown component, it has a property DisabledProperty.

We have a structure with a property:
bool Active

DisabledProperty = !Active does not work because '!Active' is not a member of the structure.

To use DisabledProperty we have to add a new property:
bool NotActive = !Active

Then we can use:
DisabledProperty = NotActive

Is there a better way?
Maybe there is another component property for that?

This is the only way.