Why did the border radius disappear for an RecyclerView item with a custom background? - android-recyclerview

Question

I try to figure out Android development, and sometimes I have beginner question. For now I faced with issue creating the RecyclerView items with different background color. I created a simple
RecyclerView items list First I set one background (light green) for all items.
Then I decided to set a separate background for each item. Here's how I did it in adapter file:
override fun onBindViewHolder(holder: ChapterListAdapter.ViewHolder, position: Int) {
holder.chapter_item.text = chapter_titles[position]
holder.chapter_details.text = chapter_descrs[position]
holder.chapter_image.setImageResource(chapter_images[position])
when(position){
0 -> holder.chapter_card.setBackgroundColor(Color.parseColor("#ff5668"))
1 -> holder.chapter_card.setBackgroundColor(Color.parseColor("#41d5e2"))
2 -> holder.chapter_card.setBackgroundColor(Color.parseColor("#4d53e0"))
3 -> holder.chapter_card.setBackgroundColor(Color.parseColor("#ff8e36"))
}
}
And it works, it may not be the right way to do it, but it works. However, there is one problem. In the screenshot, you can see that the last item has a border radius. I set the cardCornerRadius value for the element in card_layout.xml And for some reason, when I assign a custom color for an item, this value disappears. This can be seen in the screenshot. The last element with a light green background has a border radius (I did not assign a custom background color value to this element) and the first four elements that have a custom color assigned do not have a border radius.
Please tell me why this is happening and how to fix it. I need to keep the border radius for all elements.

Answer 1

I really glad I fond the error by myself. For setting the item background color I used setBackgroundColor but it's not correct in my case. In my case I have to use setCardBackgroundColor because I setting background for the CardView. Now my code looks:
override fun onBindViewHolder(holder: ChapterListAdapter.ViewHolder, position: Int) {
holder.chapter_item.text = chapter_titles[position]
holder.chapter_details.text = chapter_descrs[position]
holder.chapter_image.setImageResource(chapter_images[position])
when(position){
0 -> {
holder.chapter_card.setCardBackgroundColor(Color.parseColor("#ff5668"))
}
1 -> {
holder.chapter_card.setCardBackgroundColor(Color.parseColor("#41d5e2"))
}
2 -> {
holder.chapter_card.setCardBackgroundColor(Color.parseColor("#4d53e0"))
}
3 -> {
holder.chapter_card.setCardBackgroundColor(Color.parseColor("#ff8e36"))
}
}
}
And it works well.