[Android]下拉刷新和上拉加载更多

示意图：

 

1.添加依赖

• SwipeRefreshLayout 是一个支持下拉刷新功能的布局，它是 Android Support Library 或 AndroidX 库的一部分。

• BaseQuickAdapter 是一个来自开源库 BRVAH (Base RecyclerView Adapter Helper) 的功能丰富的适配器，用于简化 RecyclerView 的适配器实现。

dependencies {
    implementation("androidx.swiperefreshlayout:swiperefreshlayout:1.1.0")
    implementation("com.github.CymChad:BaseRecyclerViewAdapterHelper:3.0.6")
}

2.布局文件

在你的布局文件中（例如 activity_main.xml），你需要有一个 RecyclerView 和一个 SwipeRefreshLayout：

<?xml version="1.0" encoding="utf-8"?>
<androidx.swiperefreshlayout.widget.SwipeRefreshLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/swipe_refresh_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recycler_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
</androidx.swiperefreshlayout.widget.SwipeRefreshLayout>

3.Activity 代码

在你的 Activity 中，设置下拉刷新和上拉加载更多：

import android.os.Bundle
import android.os.Handler
import androidx.appcompat.app.AppCompatActivity
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import androidx.swiperefreshlayout.widget.SwipeRefreshLayout
import com.chad.library.adapter.base.BaseQuickAdapter
import com.chad.library.adapter.base.listener.OnLoadMoreListener
import com.chad.library.adapter.base.viewholder.BaseViewHolder

class MainActivity : AppCompatActivity() {

    private lateinit var swipeRefreshLayout: SwipeRefreshLayout
    private lateinit var recyclerView: RecyclerView
    private lateinit var adapter: MyAdapter

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

        swipeRefreshLayout = findViewById(R.id.swipe_refresh_layout)
        recyclerView = findViewById(R.id.recycler_view)

        adapter = MyAdapter()
        recyclerView.adapter = adapter
        recyclerView.layoutManager = LinearLayoutManager(this)

        swipeRefreshLayout.setOnRefreshListener {
            // 处理刷新
            Handler().postDelayed({
                swipeRefreshLayout.isRefreshing = false
                adapter.setNewInstance(listOf("New Item 1", "New Item 2", "New Item 3"))
            }, 2000)
        }

        adapter.loadMoreModule.setOnLoadMoreListener {
            // 处理加载更多
            Handler().postDelayed({
                adapter.addData(listOf("More data 1", "More data 2"))
                adapter.loadMoreModule.loadMoreComplete()
            }, 2000)
        }

        // 可选: 自定义LoadMoreView
        adapter.loadMoreModule.loadMoreView = CustomLoadMoreView()
    }
}

class MyAdapter : BaseQuickAdapter<String, BaseViewHolder>(android.R.layout.simple_list_item_1) {
    override fun convert(holder: BaseViewHolder, item: String) {
        holder.setText(android.R.id.text1, item)
    }
}

4.自定义 LoadMoreView

package com.mofang.call.callphone.view

import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.TextView
import com.chad.library.adapter.base.loadmore.BaseLoadMoreView
import com.chad.library.adapter.base.viewholder.BaseViewHolder
import com.mofang.call.callphone.R

class CustomLoadMoreView : BaseLoadMoreView() {
    override fun getRootView(parent: ViewGroup): View {
        return LayoutInflater.from(parent.context).inflate(R.layout.costom_load_more_view, parent, false)
    }

    override fun getLoadingView(holder: BaseViewHolder): View {
        return holder.getView(R.id.loading_v)
    }

    override fun getLoadComplete(holder: BaseViewHolder): View {
        return getLoadEndView(holder)
    }

    override fun getLoadFailView(holder: BaseViewHolder): View {
        val textView = holder.getView<TextView>(R.id.load_more_text)
        textView.text = "加载失败，请重试"
        return textView
    }

    override fun getLoadEndView(holder: BaseViewHolder): View {
        val textView = holder.getView<TextView>(R.id.load_more_text)
        textView.text = "没有更多数据"
        return textView
    }

}

custom_load_more.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="10dp"
    android:gravity="center">

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <LinearLayout
            android:id="@+id/loading_v"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:orientation="horizontal">
            <ProgressBar
                android:layout_width="32dp"
                android:layout_height="32dp"
                android:layout_gravity="center_vertical"
                android:indeterminateTint="#FFFFFF" />

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="match_parent"
                android:layout_marginStart="10dp"
                android:gravity="center_vertical"
                android:text="正在加载中..."
                android:textColor="#FFFFFFFF"
                android:textSize="16sp" />
        </LinearLayout>

        <TextView
            android:id="@+id/load_more_text"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:layout_marginStart="10dp"
            android:gravity="center_vertical"
            android:text="正在加载中..."
            android:textColor="#FFFFFFFF"
            android:textSize="16sp" />

    </LinearLayout>

</RelativeLayout>