RecyclerView与SwipeRefreshLayout 刷新微件的组合使用（附demo源码）

什么是RecyclerView?

RecyclerView本身就是一个视图，与listView的使用方法大同小异，与listView相比更加灵活，能够动态的创建元素。Google现在推荐使用Recyclerview。listView,GirdView已都不被推荐使用了

如何使用RecyclerView？ 添加相关依赖

implementation'androidx.recyclerview:recyclerview:1.1.0'

定义布局管理器

你可以使用RecyclerView库的三种布局管理器之一，LinerLayoutManager，GridLayoutManager，StaggeredGridLayoutManager

例如：

LinearLayoutManager linearLayoutManager=new LinearLayoutManager(this);
recyclerView.setLayoutManager(linearLayoutManager);

定义Adapter，ViewHolder

定义Adapter，继承 RecyclerView.Adapter，一定要复写三个方法onCreateViewHolder（），onBindViewHolder（），getItemCount()。

定义ViewHolder需要继承 RecyclerView.ViewHolder

Adapter需要时会创建ViewHolder对象，创建时都会调用onCreateViewHolder（）方法，

例如：

@NonNull
@Override
public CustomAdapter.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
    View view=View.inflate(context,R.layout.simple_item,null);//R.layout.simple_item为视图项的布局
    return new ViewHolder(view);
}

通过onBindViewHolder（）将 ViewHolder 与数据相关联

例如：

@Override
public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
    holder.tv.setText(dataname[position]);//tv为TextView，dataneme[position]为要绑定的数据
    holder.iv.setImageResource(dataimage[position]);//iv为ImageView，dataImage[position]为要绑定的数据
}

SwipeRefreshLayout 下拉刷新微件 SwipeRefreshLayout的作用

灵活的向现有应用添加滑动刷新微件，检测下拉的滑动，显示一个独特的进度条，在应用里触发回调方法以实现刷新效果

如何使用SwipeRefreshLayout 添加依赖

implementation "androidx.swiperefreshlayout:swiperefreshlayout:1.0.0"

将SwipeRefreshLayout微件添加到包含视图 的现有布局文件中

例如：

定义SwipeRefreshLayout.setOnRefreshListener监听刷新手势

例如：

swipeRefreshLayout.setOnRefreshListener( new SwipeRefreshLayout.OnRefreshListener() {
    @Override
    public void onRefresh() {
        Toast toast=Toast.makeText(MainActivity.this,"欢迎来到动物世界",Toast.LENGTH_SHORT);
        toast.show();
        swipeRefreshLayout.setRefreshing(false);
    }
});

demo

实现效果：下拉刷新时重新加载，并显示提示信息框

代码：

MainActivity.java

package com.example.test3;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import androidx.swiperefreshlayout.widget.SwipeRefreshLayout;
import android.os.Bundle;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
    private  String[] names =new String[]{"Lion","Tiger","Monkey","Dog","Cat","Elephant"};
    private  int[] imageIds =new int[]{R.drawable.lion,R.drawable.tiger,R.drawable.monkey,R.drawable.dog,R.drawable.cat,R.drawable.elephant};
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        RecyclerView recyclerView=findViewById(R.id.rv);
        SwipeRefreshLayout swipeRefreshLayout=findViewById(R.id.swiperefresh);
        swipeRefreshLayout.setOnRefreshListener( new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                Toast toast=Toast.makeText(MainActivity.this,"欢迎来到动物世界",Toast.LENGTH_SHORT);
                toast.show();
                swipeRefreshLayout.setRefreshing(false);
            }
        });
        LinearLayoutManager linearLayoutManager=new LinearLayoutManager(this);
        recyclerView.setLayoutManager(linearLayoutManager);
        CustomAdapter myAdapter=new CustomAdapter(names,imageIds,this);
        recyclerView.setAdapter(myAdapter);
    }
}

CustomerAdapter.java

package com.example.test3;
import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
public class CustomAdapter extends RecyclerView.Adapter{
    private final String[] dataname;
    private final int[] dataimage;
    private Context context;
    public CustomAdapter(String[] datanameset,int[] dataimageset,Context context) {
        this.dataname = datanameset;
        this.dataimage=dataimageset;
        this.context=context;
    }
    @NonNull
    @Override
    public CustomAdapter.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view=View.inflate(context,R.layout.simple_item,null);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
        holder.tv.setText(dataname[position]);//tv为TextView，dataneme[position]为要绑定的数据
        holder.iv.setImageResource(dataimage[position]);//iv为ImageView，dataImage[position]为要绑定的数据
    }

    @Override
    public int getItemCount() {
        return dataname.length;
    }

    public class ViewHolder extends RecyclerView.ViewHolder {
        private TextView tv;
        private ImageView iv;
        public ViewHolder(@NonNull View itemView) {
            super(itemView);
            tv=itemView.findViewById(R.id.name);
            iv=itemView.findViewById(R.id.header);
        }
    }
}

activity_main.xml

simple_item.xml

textview_border.xml(设置文本边框的drawable文件)