offset set with getItemOffsets disappears after scroll

Question

I have a horizontal RecyclerView which works with a FlexLayoutManager. I also have some decorations set with RecyclerView.ItemDecoration. My getItemOffsets method looks something like this:

override fun getItemOffsets(outRect: Rect, view: View, recyclerView: RecyclerView, state: RecyclerView.State) {
  super.getItemOffsets(outRect, view, recyclerView, state)
  val position: Int = recyclerView.getChildAdapterPosition(view)
  if(position meets some rules){
    outRect.top = some values here
  }

  if(viewType == CERTAIN_VIEW_TYPE){
    outRect.bottom = some value
  }
}

 ..onDrawOver(){ 
     //I draw the decorations here
   }

This works, the views that I set as decorations are shown and they are at the right position.

The problem that I have is that AFTER I SCROLL TO RIGHT AND THEN BACK TO LEFT, the offset set by outRect.top is set to 0 and my decorations overlap my items.

The curious stuff is that offset set by outRect.bottom doesn't disappear or cause any issues.

I just specify that the offset set by outRect.top is set only for certain positions.

Also my decorations don't disappear, just the margin set initially by outRect.top is not there anymore

Can you please help me with this issue?

Thank you

EDIT: This can be the result of view recycling I guess, because I see that after scroll other items now have top offset even though I did not intend to set it for them

Answer 1

I had the same problem with item offsets when scrolling. My case was -> I had a RecyclerView with a GridLayoutManager, orientation was horizontal and span count set to 2

I've added a custom item decoration to the RecyclerView related to the requirements that I had, by just adding some space around the items and making calculations.

Used the same overridden function as you and set the value to top, bottom, left and right.

Anyway the problem that I had, was at how I was getting the position of the view that I wanted to make my changes.

val viewHolder = recyclerView.findContainingViewHolder(view) ?: return
val adapterPosition = viewHolder.absoluteAdapterPosition
val childPosition = parent.indexOfChild(view)
val isEvenPosition = adapterPosition % 2 == 0

Previously I was using childPosition but when scrolling I was having the problem, when I've used adapterPosition the views were getting the correct amount of space.