src/com/android/wallpaper/widget/GridRowSpacerDecoration.kt

/*
 * Copyright (C) 2022 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.android.wallpaper.widget

import android.graphics.Rect
import android.view.View
import androidx.recyclerview.widget.GridLayoutManager
import androidx.recyclerview.widget.RecyclerView

/**
 * RecyclerView ItemDecorator that adds a vertical space between grid rows.
 */
class GridRowSpacerDecoration(private val padding: Int) : RecyclerView.ItemDecoration() {
    override fun getItemOffsets(
            outRect: Rect,
            view: View,
            parent: RecyclerView,
            state: RecyclerView.State) {
        val layoutManager = parent.layoutManager
        if (layoutManager is GridLayoutManager) {
            val position = parent.getChildAdapterPosition(view)
            if (position >= layoutManager.spanCount) {
                outRect.top = padding
            }
        }
    }
}