How to make android layout background transparent?

Question

How to make RecyclerView item background transparent I need to show background image?

I tried 3 solutions given in Stack Overflow and not worked for me

1 : android:background="?android:attr/selectableItemBackground"<br>
2 : android:background="@android:color/transparent"<br>
3 : alpfha 0.4

udated i also tried
4: android:background="@null" (Answer from this post) and not working

full xml code

Answer 1

Try to give this on your item CardView

 app:cardBackgroundColor="@android:color/transparent"

Answer 2

So for the layout you are inflating for the item you can use android:background="@null"

You can also use developer options on your device to see layout bounds or check the view hierarchy to see which item is giving you problems