由于kotlin中的泛型,无法实例化适配器包装器

由于泛型的原因,我无法将适配器传递给适配器包装类。下面是我如何实例化它

val a = MyAdapter()
val b = AdAdapter(a)

此代码导致错误

Type mismatch: inferred type is MyAdapter but RecyclerView.Adapter
<in RecyclerView.ViewHolder> was expected

这是我的适配器

class MyAdapter: RecyclerView.Adapter<MyAdapter.VH>() {

    //Some Code Here

    class VH(itemView: View): RecyclerView.ViewHolder(itemView) {}

}

这是适配器

class AdAdapter(private val originalAdapter: 
                      RecyclerView.Adapter<in RecyclerView.ViewHolder>)
                      : RecyclerView.Adapter<RecyclerView.ViewHolder>() {

    //Some Code

}