Android Studio一些view的用法（RecycleView技术流行）_android studio中view的用法

Adapter的初步使用

ListView与Simple Adapter

官方文档

public SimpleAdapter(Context context, List<? extends Map<String, ?>> data,
            @LayoutRes int resource, String[] from, @IdRes int[] to) {
        mData = data;
        mResource = mDropDownResource = resource;
        mFrom = from;
        mTo = to;
        mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }
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package com.example.view;

import androidx.appcompat.app.AppCompatActivity;

import android.annotation.SuppressLint;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;

import java.util.AbstractList;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class MainActivity extends AppCompatActivity {
    private final String NAME="name";
    private final String SEX="sex";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

//        //第一部分
//        String[] array = {
//                "北京",
//                "田径",
//                "大同",
//                "上海",
//                "天津",
//                "湖北"
//        };
//        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,R.layout.item,array);
//        ListView listView = findViewById(R.id.listView);
//        listView.setAdapter(adapter);
        //第二部分
        String[] names = {"syz","wkx"};
        String[] sexs = {"nan","nv"};
        List<Map<String,Object>> list = new ArrayList<Map<String,Object>>();
        for(int i = 0;i<names.length;i++){
            Map<String,Object> item = new HashMap<String,Object>();
            item.put(NAME,names[i]);
            item.put(SEX,sexs[i]);
            list.add(item);
        }

        SimpleAdapter adapter1 = new SimpleAdapter(this,list,R.layout.item,new String[]{NAME,SEX},new int[]{R.id.textView1,R.id.textView2});

        ListView listView = findViewById(R.id.listView);
        listView.setAdapter(adapter1);
    }
}

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RecycleView的官方解释

三部分，找控件----》布局管理----》数据显示**

 public class MyActivity extends Activity {
        private RecyclerView recyclerView;
        private RecyclerView.Adapter mAdapter;
        private RecyclerView.LayoutManager layoutManager;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.my_activity);
            recyclerView = (RecyclerView) findViewById(R.id.my_recycler_view);

            // use this setting to improve performance if you know that changes
            // in content do not change the layout size of the RecyclerView
            recyclerView.setHasFixedSize(true);

            // use a linear layout manager
            layoutManager = new LinearLayoutManager(this);
            recyclerView.setLayoutManager(layoutManager);

            // specify an adapter (see also next example)
            mAdapter = new MyAdapter(myDataset);
            recyclerView.setAdapter(mAdapter);
        }
        // ...
    }

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RecycleView三部曲的重要含义

开始代码

导入依赖包

dependencies {
        implementation 'com.android.support:recyclerview-v7:28.0.0'
    }
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创建item.xml布局

 <TextView
        android:id="@+id/textView"
        android:layout_width="match_parent"
        android:layout_height="20dp"
        android:layout_marginTop="10dp"
        android:text="@string/textview"
        android:gravity="center"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
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创建adapter类

package com.example.myrecycleview;

import android.view.ViewGroup;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;

public class adapter extends RecyclerView.Adapter {
    @NonNull
    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        return null;
    }

    @Override
    public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {

    }

    @Override
    public int getItemCount() {
        return 0;
    }
}

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写成的adapter

package com.example.myrecycleview;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;

import java.util.List;
import java.util.zip.Inflater;

public class adapter extends RecyclerView.Adapter<adapter.myviewholder> {
    private List<String> list;//传值的list
    private Context context;
    private View inflater;
    public adapter(Context context,List<String> list) {
        this.list = list;
        this.context = context;
    }

    @Override
    public adapter.myviewholder onCreateViewHolder( ViewGroup parent, int viewType) {
        //创建ViewHolder
        inflater = LayoutInflater.from(context).inflate(R.layout.item,parent,false);
        myviewholder myviewholder = new myviewholder(inflater);
        return myviewholder;//RecycleView的行，item.xml文件，每一行的文件，返回值
    }

    @Override
    public void onBindViewHolder(@NonNull adapter.myviewholder holder, int position) {
        holder.textView.setText(list.get(position));//获取位置为position的文本值，映射关系，数据绑定
    }

//    @Override
//    public void onBindViewHolder( RecyclerView.ViewHolder holder, int position) {
//
//    }//外层最大的ciewholder

    @Override
    public int getItemCount() {
        return list.size();//多少数据
    }

    //写自己的myviewholder
    class myviewholder extends RecyclerView.ViewHolder{
        TextView textView;
        public myviewholder(View itemView) {
            super(itemView);
            textView = itemView.findViewById(R.id.textView);
        }
    }
}

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package com.example.myrecycleview;

import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import android.content.Context;
import android.os.Bundle;

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

public class MainActivity extends AppCompatActivity {
    private List<String> mList = new ArrayList<>();
    private Context context = this;
    private adapter adapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        RecyclerView recyclerView = findViewById(R.id.recyclerView);
        //配置adapter
        initData();
        //配置LinearLayoutManager
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(context);
        linearLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);//垂直
        //创建adapter类
        adapter = new adapter(context,mList);
        //配置manager，赋值
        recyclerView.setAdapter(adapter);
        recyclerView.setLayoutManager(linearLayoutManager);
    }
    private void initData() {
        mList.add("亚特兰大老鹰");
        mList.add("夏洛特黄蜂");
        mList.add("迈阿密热火");
        mList.add("奥兰多魔术");
        mList.add("华盛顿奇才");
        mList.add("波士顿凯尔特人");
        mList.add("布鲁克林篮网");
        mList.add("纽约尼克斯");
        mList.add("费城76人");
        mList.add("多伦多猛龙");
        mList.add("芝加哥公牛");
        mList.add("克里夫兰骑士");
        mList.add("底特律活塞");
        mList.add("印第安纳步行者");
        mList.add("密尔沃基雄鹿");
        mList.add("达拉斯独行侠");
        mList.add("休斯顿火箭");
        mList.add("孟菲斯灰熊");
        mList.add("新奥尔良鹈鹕");
        mList.add("圣安东尼奥马刺");
        mList.add("丹佛掘金");
        mList.add("明尼苏达森林狼");
        mList.add("俄克拉荷马城雷霆");
        mList.add("波特兰开拓者");
        mList.add("犹他爵士");
        mList.add("金州勇士");
        mList.add("洛杉矶快船");
        mList.add("洛杉矶湖人");
        mList.add("菲尼克斯太阳");
        mList.add("萨克拉门托国王");mList.add("亚特兰大老鹰");
        mList.add("夏洛特黄蜂");
        mList.add("迈阿密热火");
        mList.add("奥兰多魔术");
        mList.add("华盛顿奇才");
        mList.add("波士顿凯尔特人");
        mList.add("布鲁克林篮网");
        mList.add("纽约尼克斯");
        mList.add("费城76人");
        mList.add("多伦多猛龙");
        mList.add("芝加哥公牛");
        mList.add("克里夫兰骑士");
        mList.add("底特律活塞");
        mList.add("印第安纳步行者");
        mList.add("密尔沃基雄鹿");
        mList.add("达拉斯独行侠");
        mList.add("休斯顿火箭");
        mList.add("孟菲斯灰熊");
        mList.add("新奥尔良鹈鹕");
        mList.add("圣安东尼奥马刺");
        mList.add("丹佛掘金");
        mList.add("明尼苏达森林狼");
        mList.add("俄克拉荷马城雷霆");
        mList.add("波特兰开拓者");
        mList.add("犹他爵士");
        mList.add("金州勇士");
        mList.add("洛杉矶快船");
        mList.add("洛杉矶湖人");
        mList.add("菲尼克斯太阳");
        mList.add("萨克拉门托国王");
    }
}


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结果展示：

参考网址：
1、https://www.jianshu.com/p/c4cfe38a91ed
2、https://developer.android.google.cn/guide/topics/ui/layout/recyclerview#java