安卓Recycleview简单的网格布局-初学者的关键点

导包 

def supportVersion = '28.0.0' 定义常量我的sdk版本为28  

implementation "com.android.support:recyclerview-v7:$supportVersion"
implementation "com.android.support:cardview-v7:$supportVersion"
implementation 'com.github.CymChad:BaseRecyclerViewAdapterHelper:2.9.42'
implementation 'com.yqritc:recyclerview-flexibledivider:1.4.0'
依赖代码为

def supportVersion = '28.0.0'
dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'androidx.appcompat:appcompat:1.0.0-beta01'
    implementation 'android.arch.navigation:navigation-fragment:1.0.0-alpha09'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.2'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test:runner:1.1.0-alpha4'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.0-alpha4'
    implementation "com.android.support:recyclerview-v7:$supportVersion"
    implementation "com.android.support:cardview-v7:$supportVersion"
    implementation 'com.github.CymChad:BaseRecyclerViewAdapterHelper:2.9.42'
    implementation 'com.yqritc:recyclerview-flexibledivider:1.4.0'

}

Adapter代码（解释都在上面）

package com.example.imageload.adapter;

import com.chad.library.adapter.base.BaseQuickAdapter;
import com.chad.library.adapter.base.BaseViewHolder;
import com.example.imageload.R;
import com.example.imageload.bean.GridBean;


import java.util.List;

//记得这里添加泛型
public class MyGridAdapter extends BaseQuickAdapter<GridBean, BaseViewHolder> {
  //  private List data=null;
    public MyGridAdapter(int layoutResId, List data) {

        super(layoutResId, data);//这里设置你的布局 Main窗口传入你的数据这里转换了封装了一下传到了convert 下的GridBean item（怎么转换你不用guan）
        //layoutResId 为你单个属性布局的ID 假如你要再屏幕上显示5张图片这个就传入你一张图片的布局文件 剩下那四张也用这个布局  要跟androidx.recyclerview.widget.RecyclerView分开

    }


    @Override
    protected void convert(BaseViewHolder helper, GridBean item) {
   helper.setText(R.id.textView_list,item.getTitle());//设置值
    helper.setImageResource(R.id.img_list,item.getImageResourse());
   helper.addOnClickListener(R.id.my_button);//添加事件
   helper.addOnClickListener(R.id.my_button2);

    }


}

bean

package com.example.imageload.bean;

public class GridBean {


    private String title;



    private  int imageResourse;

    public GridBean(String title, int imageResourse) {
        this.title = title;
        this.imageResourse = imageResourse;
    }


    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public int getImageResourse() {
        return imageResourse;
    }

    public void setImageResourse(int imageResourse) {
        this.imageResourse = imageResourse;
    }
}

Main窗口

package com.example.imageload;

import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.GridLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Toast;

import com.chad.library.adapter.base.BaseQuickAdapter;
import com.example.imageload.adapter.MyGridAdapter;
import com.example.imageload.bean.GridBean;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {
    private ArrayList<GridBean> mDataList = new ArrayList<>();    //主窗口list集合
    private RecyclerView recyclerView;
    MyGridAdapter myAdapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);//设置主布局

        recyclerView = findViewById(R.id.my_list);
        recyclerView.setLayoutManager(new GridLayoutManager(this, 3));
        initData();
        initAdapter();
    }

    private void initAdapter() {
        //这里问什么不用viewholder？viewhodler除了缓存？有什么用
        myAdapter = new MyGridAdapter(R.layout.my_item, mDataList);
        myAdapter.setOnItemChildClickListener(new BaseQuickAdapter.OnItemChildClickListener() {
            @Override
            public void onItemChildClick(BaseQuickAdapter adapter, View view, int position) {
                switch (view.getId())
                { case R.id.my_button:
                    Toast.makeText(MainActivity.this,"child按钮一被单机"+position,Toast.LENGTH_SHORT).show();
                    break;
                    case  R.id.my_button2:
                        Toast.makeText(MainActivity.this,"按钮2被单机"+position,Toast.LENGTH_SHORT).show();
                        break;
                }

            }
        });
        myAdapter.setOnItemClickListener(new BaseQuickAdapter.OnItemClickListener() {
            @Override
            public void onItemClick(BaseQuickAdapter adapter, View view, int position) {


                switch (position)
                { case 0:
//                    Intent intent= new Intent();
//                    intent.setClass(MainActivity.this,SectionActivity.class);
//                    startActivity(intent);
                    break;
                }
                Toast.makeText(MainActivity.this,"你点击了"+position,Toast.LENGTH_SHORT).show();
            }
        });
        recyclerView.setAdapter(myAdapter);//记得add
        Log.i("Mainact","初始化adapter");
    }


    private  void initData()
    {
        for (int i=0;i<10;i++)
        {
            GridBean b=new GridBean("第"+i+"个例子",R.mipmap.ic_launcher);
            mDataList.add(b);
        }

    }
}

主布局文件 activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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=".MainActivity">

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

</LinearLayout>

单个布局文件my_item.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.cardview.widget.CardView android:id="@+id/card_view"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:foreground="?android:attr/selectableItemBackground"
    xmlns:android="http://schemas.android.com/apk/res/android"
    >
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
    </LinearLayout>
    <LinearLayout
        android:layout_gravity="center"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical">
        <TextView
            android:id="@+id/dialog"
            android:layout_width="80dp"
            android:layout_height="80dp"
            android:layout_centerInParent="true"
            android:background="#9DDE76"
            android:gravity="center"
            android:textColor="#ffffffff"
            android:textSize="30dp"
            android:visibility="invisible" />
        <ImageView
            android:id="@+id/img_list"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:src="@android:mipmap/sym_def_app_icon" />

        <TextView
            android:id="@+id/textView_list"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="TextView"
            android:layout_gravity="center"
            android:textAlignment="center" />
        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:id="@+id/my_button"
            android:text="点我测试"
            />
        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:id="@+id/my_button2"
            android:text="点我测试2"
            />


    </LinearLayout>
</androidx.cardview.widget.CardView>

理解就很好理解了 不贴代码了贴图（添加装饰什么的百度，上面也有点我注释了）