RecyclerView remove divider / decorator after the last item

Question

I have a quite simple RecyclerView.
This is how I set the divider:

DividerItemDecoration itemDecorator = new DividerItemDecoration(getContext(), DividerItemDecoration.VERTICAL);
itemDecorator.setDrawable(ContextCompat.getDrawable(getActivity(), R.drawable.news_divider));
recyclerView.addItemDecoration(itemDecorator);

And this is drawable/news_divider.xml:

<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
    <solid android:color="@color/white_two"/>
    <size android:height="1dp"/>
</shape>

The problem is for some reason the divider is not just created in between the items. But also after the last item. And I want it only in between the items not after every item.

Any idea how to prevent the divider from showing after the last item?

Answer 1

Try this Code, it won't show divider for the last item. This method will give you more control over drawing divider.

public class DividerItemDecorator extends RecyclerView.ItemDecoration {
    private Drawable mDivider;

    public DividerItemDecorator(Drawable divider) {
        mDivider = divider;
    }

    @Override
    public void onDrawOver(Canvas canvas, RecyclerView parent, RecyclerView.State state) {
        int dividerLeft = parent.getPaddingLeft();
        int dividerRight = parent.getWidth() - parent.getPaddingRight();

        int childCount = parent.getChildCount();
        for (int i = 0; i <= childCount - 2; i++) {
            View child = parent.getChildAt(i);

            RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();

            int dividerTop = child.getBottom() + params.bottomMargin;
            int dividerBottom = dividerTop + mDivider.getIntrinsicHeight();

            mDivider.setBounds(dividerLeft, dividerTop, dividerRight, dividerBottom);
            mDivider.draw(canvas);
        }
    }
}

divider.xml:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <size
        android:width="1dp"
        android:height="1dp" />
    <solid android:color="@color/grey_300" />
</shape>

Set your Divider like this:

RecyclerView.ItemDecoration dividerItemDecoration = new DividerItemDecorator(ContextCompat.getDrawable(context, R.drawable.divider));
recyclerView.addItemDecoration(dividerItemDecoration);

Answer 2

If you don't like divider being drawn behind, you can simply copy or extend DividerItemDecoration class and change its drawing behaviour by modifying for (int i = 0; i < childCount; i++) to for (int i = 0; i < childCount - 1; i++)

Then add your decorator as recyclerView.addItemDecoration(your_decorator);

PREVIOUS SOLUTION:

As proposed here you can extend DividerItemDecoration like this:

recyclerView.addItemDecoration(
    new DividerItemDecoration(context, linearLayoutManager.getOrientation()) {
        @Override
        public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
            int position = parent.getChildAdapterPosition(view);
            // hide the divider for the last child
            if (position == state.getItemCount() - 1) {
                outRect.setEmpty();
            } else {
                super.getItemOffsets(outRect, view, parent, state);
            }
        }
    }
);

@Rebecca Hsieh pointed out:

This works when your item view in RecyclerView doesn't have a transparent background, for example,

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:background="#ffffff">
    ... 
</LinearLayout>

DividerItemDecoration.getItemOffsets is called by RecyclerView to measure the child position. This solution will put the last divider behind the last item. Therefore the item view in RecyclerView should have a background to cover the last divider and this makes it look like hidden.

Answer 3

Here is Kotlin version of accepted answer :

class DividerItemDecorator(private val divider: Drawable?) : RecyclerView.ItemDecoration() {

    override fun onDrawOver(canvas: Canvas, parent: RecyclerView, state: RecyclerView.State) {
        val dividerLeft = parent.paddingLeft
        val dividerRight = parent.width - parent.paddingRight
        val childCount = parent.childCount
        for (i in 0..childCount - 2) {
            val child: View = parent.getChildAt(i)
            val params =
                child.layoutParams as RecyclerView.LayoutParams
            val dividerTop: Int = child.bottom + params.bottomMargin
            val dividerBottom = dividerTop + (divider?.intrinsicHeight?:0)
            divider?.setBounds(dividerLeft, dividerTop, dividerRight, dividerBottom)
            divider?.draw(canvas)
        }
    }
}