A holder is a caching mechanism for Android
The number of holders in the RecyclerView is limited, but the number in the List is large. When the display mode of the View in the holder is changed and then deleted, it is not the holder that is deleted, but the data in the knowledge List that is actually deleted.
Two solutions
Set a flag in the List. If the flag is true, it will be displayed in a special way. If the flag is false, it will not be displayed in a special way.