DividerItemDecoration.java

/**
 * Divider for RecyclerView list items
 * <p>
 * Created by Dmitriy V. Chernysh on 24.09.16.
 * [email protected]
 * <p>
 * www.mobile-dev.pro
 */

public class DividerItemDecoration extends RecyclerView.ItemDecoration {

    private Drawable mDrawableDivider;

    public DividerItemDecoration(Drawable drawableDivider) {
        mDrawableDivider = drawableDivider;
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        super.getItemOffsets(outRect, view, parent, state);
        if (parent.getChildAdapterPosition(view) == 0) {
            return;
        }

        outRect.top = mDrawableDivider.getIntrinsicHeight();
    }

    @Override
    public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
        Log.d(Constants.LOG_TAG_DEBUG, "DividerItemDecoration.onDraw(): ");
        int dividerLeft = parent.getPaddingLeft();
        int dividerRight = parent.getWidth() - parent.getPaddingRight();

        int childCount = parent.getChildCount();
        for (int i = 0; i < childCount - 1; i++) {
            View child = parent.getChildAt(i);

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

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

            mDrawableDivider.setBounds(dividerLeft, dividerTop, dividerRight, dividerBottom);
            mDrawableDivider.draw(c);
        }
    }
}