安卓中RecyclerView的簡單使用和自定義RecyclerView的接口點擊監聽事件

初學者RecyclerView的難點和重點在適配器Adapter裏,剛開始有點難理解
1.先創建RecyclerView的item的xml文件
2.創建點擊事件接口
4.創建ViewHolder類
3.自定義適配器 適配器裏實現接口

使用RecyclerView先在build.gradle裏添加依賴,如下:
compile ‘com.android.support:recyclerview-v7:26.0.+’

注意:RecyclerView依賴的版本要與自己安卓stuidio系統的
compile ‘com.android.support:appcompat-v7:26.+’的版本一樣

首先xml文件裏：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="ydtx.bwie.com.recyclerviewtext.MainActivity">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/relist"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
    </android.support.v7.widget.RecyclerView>


</RelativeLayout>

item佈局：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/tv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
</LinearLayout>

點擊事件接口：

import android.view.View;

/**
 * Created by 王 on 2017/10/11.
 */

public interface OnClickRecyclerListner {
    //點擊的接口
    void onItemclick(View view,int position);
    //長按的接口
    void onLongItemclick(View view,int position);
}

ViewHolder：

import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.view.textservice.TextInfo;
import android.widget.TextView;

import org.w3c.dom.Text;

/**
 * Created by 王 on 2017/10/11.
 */

public class MyViewHolder extends RecyclerView.ViewHolder {
    public TextView tv;

    //構造方法 待會適配器裏創建時傳進來view 就去找id 其實和Listview的Viewholder的優化是一樣的道理
    public MyViewHolder(View itemView) {
        super(itemView);
        tv = itemView.findViewById(R.id.tv);
    }
}

重點:自定義設配器Adapter

import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListView;

import java.util.ArrayList;
import java.util.List;

/**
 * Created by 王 on 2017/10/11.
 */

public class MyAdapter extends RecyclerView.Adapter<MyViewHolder> {
    private Context context;

    private List<String> data = new ArrayList<>();
    //創建接口對象
    private OnClickRecyclerListner listner;

    public MyAdapter(Context context) {
        this.context = context;
        //初始化數據
        for (int i = 0; i < 20; i++) {
            data.add("ddd" + i);
        }
    }

    //創建接口點擊事件的方法
    public void setLisner(OnClickRecyclerListner lisner) {
        this.listner = lisner;
    }


    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        //填充item佈局
        View view = View.inflate(context, R.layout.item, null);
        //創建Viewholder然後把view對象傳進去 viewholder從這個view對象裏找id 
        final MyViewHolder holder = new MyViewHolder(view);
        //判斷是否設置了點擊事件
        if (listner != null) {
            view.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    //getLayoutPosition獲取點擊條目的位置 
                 listner.onItemclick(view,holder.getLayoutPosition());
                }
            });
            view.setOnLongClickListener(new View.OnLongClickListener() {
                @Override
                public boolean onLongClick(View view) {
                   listner.onLongItemclick(view,holder.getLayoutPosition());
                    //爲了防止與點擊衝突 改爲true禁止繼續事傳遞
                    return true;
                }
            });
        }
        return holder;
    }

    //給每一個條目賦值
    @Override
    public void onBindViewHolder(MyViewHolder holder, int position) {
        holder.tv.setText(data.get(position));
    }

    //獲取條目數量
    @Override
    public int getItemCount() {
        return data.size();
    }


}

ManActivity裏：

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.DividerItemDecoration;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.StaggeredGridLayoutManager;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    private RecyclerView relist;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        relist = (RecyclerView) findViewById(R.id.relist);
        //樣式管理器1 自己試着玩玩吧
        //relist.setLayoutManager(new LinearLayoutManager(this));
        //樣式管理器2
        relist.setLayoutManager(new StaggeredGridLayoutManager(1, StaggeredGridLayoutManager.HORIZONTAL));
        //樣式管理器3
        // relist.setLayoutManager(new GridLayoutManager(this,3));
        MyAdapter adapter = new MyAdapter(this);
        relist.setAdapter(adapter);
        //添加分割線
        relist.addItemDecoration(new DividerItemDecoration(this, DividerItemDecoration.VERTICAL));
        //點擊事件 注意是adapter不是recyclerview對象，調用的是adapter裏的接口點擊方法
        adapter.setLisner(new OnClickRecyclerListner() {
            @Override
            public void onItemclick(View view, int position) {
                Toast.makeText(MainActivity.this, position + "", Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onLongItemclick(View view, int position) {
                Toast.makeText(MainActivity.this, position + "", Toast.LENGTH_SHORT).show();
            }
        });

    }


}

效果如下：

樣式管理器非常多變靈活 自己試驗吧~ 很有意思