pub type UITraitChangeHandler = *mut DynBlock<dyn Fn(NonNull<ProtocolObject<dyn UITraitEnvironment>>, NonNull<UITraitCollection>)>;Available on crate features
block2 and UITraitCollection only.pub type UITraitChangeHandler = *mut DynBlock<dyn Fn(NonNull<ProtocolObject<dyn UITraitEnvironment>>, NonNull<UITraitCollection>)>;block2 and UITraitCollection only.