Android RecyclerView AsyncListUtil手动刷新fillData，kotlin

妖狐艹你老母 2023-10-13 10:36 2阅读 0赞

implementation 'com.github.bumptech.glide:glide:4.15.1'
        implementation 'androidx.constraintlayout:constraintlayout:1.1.3'

![8164beb3cf414aa6939cb6c01531a4c8.png][]

import android.os.Bundle
    import android.util.Log
    import android.view.View
    import androidx.appcompat.app.AppCompatActivity
    import androidx.recyclerview.widget.GridLayoutManager
    import androidx.recyclerview.widget.RecyclerView
    import androidx.recyclerview.widget.RecyclerView.OnScrollListener
    import com.google.android.material.floatingactionbutton.FloatingActionButton
    import com.google.android.material.snackbar.Snackbar
    
    
    class MainActivity : AppCompatActivity() {
        companion object {
            const val TAG = "fly"
        }
    
        private var mRecyclerView: RecyclerView? = null
        private val mItems = ArrayList<MyData>()
        private var fromPos: Int = 0
        private var toPos: Int = 0
        private var startPosition: Int = 0
        private var itemCount: Int = 0
    
        override fun onCreate(savedInstanceState: Bundle?) {
            super.onCreate(savedInstanceState)
            setContentView(R.layout.activity_main)
    
            mRecyclerView = findViewById(R.id.recycler_view)
            mRecyclerView?.layoutManager = GridLayoutManager(this, 3).apply {
                orientation = GridLayoutManager.VERTICAL
            }
    
            repeat(1000) {
                val data = MyData("-", "-", R.drawable.ic_launcher_background)
                mItems.add(data)
            }
    
            val mAdapter = MyAdapter(mItems)
            mRecyclerView?.adapter = mAdapter
    
            MyPagingRecyclerViewUtil.PAGE_SIZE = 50
            var mRecyclerViewUtil = MyPagingRecyclerViewUtil(mRecyclerView!!,
                object : MyPagingRecyclerViewUtil.PagingListener {
                    override fun onFillData(
                        data: Array<out Any>, startPosition: Int, itemCount: Int
                    ) {
                        this@MainActivity.startPosition = startPosition
                        this@MainActivity.itemCount = itemCount
    
                        Log.d(TAG, "onFillData $startPosition $itemCount")
                        fillData(startPosition, itemCount)
                    }
    
                    override fun onVisibleRange(fromPos: Int, toPos: Int) {
                        this@MainActivity.fromPos = fromPos
                        this@MainActivity.toPos = toPos
                    }
    
                    override fun refreshData(): Int {
                        return mItems.size
                    }
                })
    
            mRecyclerView?.addOnScrollListener(object : OnScrollListener() {
                override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
                    mRecyclerViewUtil?.onRangeChanged()
                }
            })
    
            //打开即滚到到最后
            mRecyclerView?.scrollToPosition(mAdapter.itemCount - 1)
    
            val fab: FloatingActionButton = findViewById(R.id.fab)
            fab.setOnClickListener { view ->
                Snackbar.make(
                    view,
                    "视野:$fromPos->$toPos\n已加载:$startPosition-$itemCount",
                    Snackbar.LENGTH_LONG
                ).setAction(
                    "点击这里加载视野外:${startPosition - itemCount}-$itemCount",
                    object : View.OnClickListener {
                        override fun onClick(v: View?) {
                            fillData(startPosition - itemCount, itemCount)
                        }
                    }).show()
            }
        }
    
        fun fillData(start: Int, count: Int) {
            var pos: Int
            for (i in 0 until count) {
                pos = start + i
                var data = mItems[pos]
    
                data.pos = "pos:$pos"
                data.text = "text:$pos"
                data.resId = R.drawable.ic_launcher_foreground
            }
    
            Log.d(TAG, "已加载->$start $count")
            runOnUiThread { mRecyclerView?.adapter?.notifyDataSetChanged() }
        }
    }

<?xml version="1.0" encoding="utf-8"?>
    <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:context=".MainActivity">
    
        <androidx.recyclerview.widget.RecyclerView
            android:id="@+id/recycler_view"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            tools:context=".MainActivity" />
    
        <com.google.android.material.floatingactionbutton.FloatingActionButton
            android:id="@+id/fab"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="end|bottom"
            android:layout_margin="16dp"
            android:contentDescription="更新"
            android:src="@android:drawable/ic_menu_add" />
    </FrameLayout>

import android.view.LayoutInflater
    import android.view.View
    import android.view.ViewGroup
    import android.widget.ImageView
    import android.widget.TextView
    import androidx.recyclerview.widget.RecyclerView
    import com.bumptech.glide.Glide
    
    class MyAdapter(private var items: ArrayList<MyData>) : RecyclerView.Adapter<MyViewHolder>() {
        override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
            val view = LayoutInflater.from(parent.context)
                .inflate(R.layout.item, parent, false)
            return MyViewHolder(view)
        }
    
        override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
            Glide.with(holder.itemView.context).load(items?.get(position)?.resId).into(holder.image)
            holder.pos.text = items?.get(position)?.pos
            holder.text.text = items?.get(position)?.text
        }
    
        override fun getItemCount(): Int {
            return items?.size!!
        }
    }
    
    class MyViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        val image: ImageView = itemView.findViewById(R.id.image)
        val pos: TextView = itemView.findViewById(R.id.pos)
        val text: TextView = itemView.findViewById(R.id.text)
    }
    
    data class MyData(var pos: String, var text: String, var resId: Int?)

<?xml version="1.0" encoding="utf-8"?>
    <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:paddingTop="5dp"
        android:paddingBottom="5dp">
    
        <ImageView
            android:id="@+id/image"
            android:layout_width="wrap_content"
            android:layout_height="50dp"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent" />
    
        <TextView
            android:id="@+id/pos"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:text="-"
            android:textColor="@android:color/darker_gray"
            android:textSize="15dp"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toBottomOf="@id/image" />
    
        <TextView
            android:id="@+id/text"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:text="-"
            android:textColor="@color/black"
            android:textSize="12dp"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toBottomOf="@id/pos" />
    </androidx.constraintlayout.widget.ConstraintLayout>

import android.util.Log
    import androidx.annotation.UiThread
    import androidx.annotation.WorkerThread
    import androidx.recyclerview.widget.AsyncListUtil
    import androidx.recyclerview.widget.GridLayoutManager
    import androidx.recyclerview.widget.RecyclerView
    
    
    class MyPagingRecyclerViewUtil(rv: RecyclerView, pagingListener: PagingListener) {
        companion object {
            var PAGE_SIZE = 200
        }
    
        private var mAsyncListUtil: AsyncListUtil<Any>? = null
    
        init {
            var viewCallback = PagingViewCallback(rv, pagingListener)
            var dataCallback = PageingDataCallback(pagingListener)
            mAsyncListUtil =
                AsyncListUtil(Any().javaClass, PAGE_SIZE, dataCallback, viewCallback)
        }
    
        fun onRangeChanged() {
            mAsyncListUtil?.onRangeChanged()
        }
    
        fun refresh() {
            Log.d(MainActivity.TAG, "refresh")
            mAsyncListUtil?.refresh()
        }
    
        private class PageingDataCallback(var listener: PagingListener) :
            AsyncListUtil.DataCallback<Any>() {
    
            // 如果RecyclerView的数据源总长度发生变化，需要更新这个值,
            // 否则getItemRangeInto不会触发新的可视区域range更新。
            override fun refreshData(): Int {
                return listener?.refreshData() ?: 0
            }
    
            @WorkerThread
            override fun fillData(data: Array<out Any>, startPosition: Int, itemCount: Int) {
                listener?.onFillData(data, startPosition, itemCount)
            }
        }
    
        private class PagingViewCallback(val recyclerView: RecyclerView, var listener: PagingListener) :
            AsyncListUtil.ViewCallback() {
            fun getOutRange(rv: RecyclerView, outRange: IntArray) {
                outRange[0] = (rv.layoutManager as GridLayoutManager?)!!.findFirstVisibleItemPosition()
                outRange[1] = (rv.layoutManager as GridLayoutManager?)!!.findLastVisibleItemPosition()
            }
    
            override fun getItemRangeInto(outRange: IntArray) {
                getOutRange(recyclerView, outRange)
                listener?.onVisibleRange(outRange[0], outRange[1])
            }
    
            override fun onDataRefresh() {
                Log.d(MainActivity.TAG, "onDataRefresh")
            }
    
            override fun onItemLoaded(position: Int) {
                Log.d(MainActivity.TAG, "onItemLoaded $position")
            }
        }
    
        interface PagingListener {
            @WorkerThread
            fun onFillData(data: Array<out Any>, startPosition: Int, itemCount: Int) {
    
            }
    
            @UiThread
            fun onVisibleRange(fromPos: Int, toPos: Int) {
    
            }
    
            fun refreshData(): Int {
                return 0
            }
        }
    }

[Android RecyclerView paging/pager/page implements based on AsyncListUtil，kotlin\_zhangphil的博客-CSDN博客基于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）![favicon32.ico][]https://blog.csdn.net/zhangphil/article/details/130874429][Android RecyclerView paging_pager_page implements based on AsyncListUtil_kotlin_zhangphil_-CSDN_Android_Paging Library_RecyclerView_RecyclerView_Android_AsyncListUtil_1_Android_Paging Library_RecyclerView_RecyclerView_Android_AsyncListUtil_1_Android Paging 3_kotlin_1_favicon32.ico_https_blog.csdn.net_zhangphil_article_details_130874429]

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[favicon32.ico]: https://g.csdnimg.cn/static/logo/favicon32.ico
[Android RecyclerView paging_pager_page implements based on AsyncListUtil_kotlin_zhangphil_-CSDN_Android_Paging Library_RecyclerView_RecyclerView_Android_AsyncListUtil_1_Android_Paging Library_RecyclerView_RecyclerView_Android_AsyncListUtil_1_Android Paging 3_kotlin_1_favicon32.ico_https_blog.csdn.net_zhangphil_article_details_130874429]: https://blog.csdn.net/zhangphil/article/details/130874429