RecyclerView的几种Decoration

RecyclerView的几种Decoration

import android.content.res.Resources
import android.graphics.Rect
import android.util.TypedValue
import android.view.View
import androidx.recyclerview.widget.RecyclerView

class SimplePaddingDecoration(
    spaceDp: Int,
    val orientation: Int = RecyclerView.VERTICAL
) : RecyclerView.ItemDecoration() {
    private val dividerHeight: Int = TypedValue.applyDimension(
        TypedValue.COMPLEX_UNIT_DIP,
        spaceDp.toFloat(),
        Resources.getSystem().displayMetrics
    ).toInt()

    override fun getItemOffsets(
        outRect: Rect,
        view: View,
        parent: RecyclerView,
        state: RecyclerView.State
    ) {
        val position = (view.layoutParams as RecyclerView.LayoutParams).viewLayoutPosition

        if (orientation == RecyclerView.VERTICAL) {
            // 竖直
            if (position + 1 != parent.adapter?.itemCount) {
                outRect.set(0, 0, 0, dividerHeight)
            } else {
                outRect.set(0, 0, 0, 0)
            }
        } else {
            // 水平
            if (position + 1 != parent.adapter?.itemCount) {
                outRect.set(0, 0, dividerHeight, 0)
            } else {
                outRect.set(0, 0, 0, 0)
            }
        }
    }
}