ExpandableGroup constructor can cause ClassCastException

[lukasz-kalnik-gcx]

The constructor ExpandableGroup(Group) immediately casts its Group argument to ExpandableItem which is not guaranteed to succeed in any way (a Group does not extend ExpandableItem). This can lead to a ClassCastException at runtime.

Example:

val parent = CardItem(rainbow200[0])
val expandableGroup = ExpandableGroup(parent)

java.lang.ClassCastException: com.xwray.groupie.example.viewbinding.item.CardItem cannot be cast to com.xwray.groupie.ExpandableItem

Solution would be probably to make ExpandableItem extend Group (like e.g. also Item does) and change the ExpandableGroup constructor parameter and parent field type to ExpandableItem.

[Zhuinden]

Yes, this is true. I always wondered why ExpandableGroup takes a Group instead of an ExpandableItem, when it requires an ExpandableItem either way.