Android RecyclerView AsyncListDiffer DiffUtil，Kotlin（a）

Kotlin 复制代码

import android.graphics.Color
import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import androidx.appcompat.app.AppCompatActivity
import androidx.recyclerview.widget.AsyncListDiffer
import androidx.recyclerview.widget.DiffUtil
import androidx.recyclerview.widget.GridLayoutManager
import androidx.recyclerview.widget.RecyclerView
import kotlin.random.Random

const val ITEM_COUNT = 30

class MainActivity : AppCompatActivity() {
    private var mAdapter: MyAdapter? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val rv = findViewById<RecyclerView>(R.id.rv)
        val layoutManager = GridLayoutManager(this, 3)
        rv.layoutManager = layoutManager

        mAdapter = MyAdapter()
        rv.adapter = mAdapter
    }

    override fun onResume() {
        super.onResume()

        val list = mutableListOf<MyItem>()
        for (i in 0 until ITEM_COUNT) {
            val item = MyItem()
            item.pos = i
            item.change = Random.Default.nextBoolean()
            item.time = System.currentTimeMillis()
            list.add(item)
        }

        mAdapter?.onChange(list)
    }

    class MyAdapter : RecyclerView.Adapter<MyVH> {
        private var mDiffer = AsyncListDiffer(this, object : DiffUtil.ItemCallback<MyItem>() {
            override fun areItemsTheSame(oldItem: MyItem, newItem: MyItem): Boolean {
                return oldItem.pos == newItem.pos
            }

            override fun areContentsTheSame(oldItem: MyItem, newItem: MyItem): Boolean {
                return oldItem == newItem
            }

            override fun getChangePayload(oldItem: MyItem, newItem: MyItem): Any? {
                return super.getChangePayload(oldItem, newItem)
            }
        })

        constructor() {
            val list = mutableListOf<MyItem>()
            for (i in 0 until ITEM_COUNT) {
                val item = MyItem()
                item.pos = i
                item.change = false
                item.time = 0L
                list.add(item)
            }

            onChange(list)
        }

        fun onChange(list: MutableList<MyItem>) {
            mDiffer.submitList(list)
        }

        override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyVH {
            val view = LayoutInflater.from(parent.context).inflate(android.R.layout.simple_list_item_2, parent, false)
            return MyVH(view)
        }

        override fun getItemCount(): Int {
            return mDiffer.currentList.size
        }

        override fun onBindViewHolder(holder: MyVH, position: Int) {
            holder.text1.text = "pos=${mDiffer.currentList[position].pos}"
            holder.text2.text = "time=${mDiffer.currentList[position].time}"

            if (mDiffer.currentList[position].change) {
                holder.text1.setTextColor(Color.RED)
                holder.text2.setTextColor(Color.RED)
            } else {
                holder.text1.setTextColor(Color.BLACK)
                holder.text2.setTextColor(Color.BLACK)
            }
        }
    }

    class MyVH(itemView: View) : RecyclerView.ViewHolder(itemView) {
        val text1: TextView = itemView.findViewById(android.R.id.text1)
        val text2: TextView = itemView.findViewById(android.R.id.text2)
    }

    class MyItem {
        var change = false
        var pos = 0
        var time = 0L

        override fun equals(other: Any?): Boolean {
            return pos == (other as MyItem).pos && time == other.time
        }
    }
}

Android RecyclerView AsyncListUtil手动刷新fillData，kotlin_recycler refresh data-CSDN博客文章浏览阅读410次。基于Android官方Paging Library的RecyclerView分页加载框架我之前写了一篇RecyclerView分页加载机制的文章，是基于Android官方的AsyncListUtil实现的，详情见附录文章1。基于Android官方Paging Library的RecyclerView分页加载框架我之前写了一篇RecyclerView分页加载机制的文章，是基于Android官方的AsyncListUtil实现的，详情见附录文章1。【代码】Android Paging 3,kotlin（1）_recycler refresh datahttps://blog.csdn.net/zhangphil/article/details/131519811