Adapter的使用

适配器在Android编程中经常用到，我记录以下我学习BaseAdapter的过程

BaseAdapter

创建三个java类，一个是主要的活动类，一个是数据类，一个是适配器类

数据类中需要填入所需的变量

package com.phc.a1801_penghaicen_listview;
   
/**
 * @author PengHaiChen
 */
//该类代表人员信息
public  class Person {
    int image;
    String name;
    String sex;
    String class_;
	String classRome;
   
    public void setImage(int image) {
        this.image = image;
    }
   
    public void setName(String name) {
        this.name = name;
    }
   
    public void setSex(String sex) {
        this.sex = sex;
    }
   
    public void setClass_(String class_) {
        this.class_ = class_;
    }
   
    public void setClassRome(String classRome) {
        this.classRome = classRome;
    }
   
    public int getImage() {
        return image;
    }
   
    public String getName() {
        return name;
    }
   
    public String getSex() {
        return sex;
    }
   
    public String getClass_() {
        return class_;
    }
   
    public String getClassRome() {
        return classRome;
    }
   
    public Person(int image, String name, String sex, String class_, String classRome) {
        this.image = image;
        this.name = name;
        this.sex = sex;
        this.class_ = class_;
        this.classRome = classRome;
    }
   
       
}

适配器中的代码

package com.phc.a1801_penghaicen_listview;
   
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
   
import java.util.List;
   
/**佛曰适配器,既非适配器,是名适配器
 * 这里需要完成将传递进来的参数给适配进组件中
 * @author PengHaiChen
 */
public class myBaseAdapter extends BaseAdapter {
   
    List<Person> list;
    Context context;
   
    //构造方法,将传递进来的参数变为该方法的全局变量
    public myBaseAdapter (Context context, List<Person> list){
        this.list=list;
        this.context =context;
    }
   
    @Override
    public int getCount() {
        return list.size();
    }
   
    @Override
    public Object getItem(int position) {
        return list.get(position);
    }
   
    @Override
    public long getItemId(int position) {
        return position;
    }
   
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        //这里进行填充操作
        ViewHold vh;
   
        //如果需要改造的视图是空的
        if (convertView==null){
            //填充自定义的xml
            convertView = LayoutInflater.from(context).inflate(R.layout.list_content_test, null);
            //创建对象
            vh=new ViewHold();
            //将组件赋值给vh中的变量
            vh.img=(ImageView)convertView.findViewById(R.id.list_image);
            vh.name=(TextView)convertView.findViewById(R.id.name);
            vh.sex=(TextView)convertView.findViewById(R.id.sex);
            vh.class_=(TextView)convertView.findViewById(R.id.class_);
            vh.ClassRoom=(TextView)convertView.findViewById(R.id.classRoom);
            convertView.setTag(vh);
        }else {
            vh=(ViewHold) convertView.getTag();
        }
        //将数组中对应位置的元素资源设置好
        vh.img.setImageResource(list.get(position).image);
        vh.name.setText(list.get(position).name);
        vh.sex.setText(list.get(position).sex);
        vh.class_.setText(list.get(position).class_);
        vh.ClassRoom.setText(list.get(position).classRome);
        //返回视图
        return convertView;
    }
   
    //该类代表了所有要用到的对象
    static class ViewHold{
        ImageView img;
        TextView name,sex,class_,ClassRoom;
    }
   
}

最后在主类中调用

package com.phc.a1801_penghaicen_listview;
   
import androidx.appcompat.app.AppCompatActivity;
   
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.media.Image;
import android.os.BaseBundle;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.TextView;
   
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
   
/**
 *
 * @author PengHaiChen
 */
//修改继承去除顶部栏
public class MainActivity extends Activity {
    private ListView listView;
    myBaseAdapter myBaseAdapter;
    List <Person>personList =new ArrayList<>();
    Person person;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //我需要在这里调用适配器方法,然后给参数给适配器
        initView();
        for (int i = 0; i < 20; i++) {
            person = new Person(0,"流缠子"+(i+1),"女","打架部","7#425");
            person.setImage(R.drawable.image);
            personList.add(person);
        }
        myBaseAdapter=new myBaseAdapter(this,personList);
        listView.setAdapter(myBaseAdapter);
    }
    private void initView(){
        listView=(ListView)findViewById(R.id.listView);
    }
}

BaseAdapter 还有一种需要设置不同的参数的是否可以尝试以下的方法

适配器

package com.phc.a2020_3_17;
   
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;
   
import java.util.List;
import java.util.Map;
   
public class myAdapter extends BaseAdapter {
   
    List<Map<String,Object>> datas;
    Context context;
    module md;
   
    public myAdapter(List<Map<String, Object>> datas, Context context) {
        this.datas = datas;
        this.context = context;
    }
   
    @Override
    public int getCount() {
        return datas.size();
    }
   
    @Override
    public Object getItem(int position) {
        return datas.get(position);
    }
   
    @Override
    public long getItemId(int position) {
        return position;
    }
   
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        if (convertView==null){
            convertView= LayoutInflater.from(context).inflate(R.layout.grid_view_content,null);
            md=new module();
            md.name=(TextView) convertView.findViewById(R.id.descriptionText);
            md.number=(TextView)convertView.findViewById(R.id.number);
            convertView.setTag(md);
        }else {
            md = (module) convertView.getTag();
        }
        md.name.setText(datas.get(position).get("name").toString());
        md.number.setText(datas.get(position).get("number").toString());
        return convertView;
    }
    public class module{
        TextView name,number;
    }
}

调用方法

package com.phc.a2020_3_17;
      
import androidx.appcompat.app.AppCompatActivity;
      
import android.app.Activity;
import android.os.Bundle;
import android.view.WindowManager;
import android.widget.GridLayout;
import android.widget.GridView;
      
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
      
public class MainActivity extends Activity {
    GridView gridView;
    myAdapter adapter;
    List<Map<String,Object>> data=new ArrayList<>();
      
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //关闭状态栏
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
        //调用数据方法的空参构造
        initData();
        //调用组件
        gridView=(GridView)findViewById(R.id.gridView);
        //调用适配器方法
        adapter=new myAdapter(data,this);
        //将适配器设置给组件
        gridView.setAdapter(adapter);
      
    }
    //自定义数据类
    private void initData(){
        Map<String,Object> map = new HashMap<>();
        map.put("name","温度");
        map.put("number","30");
        data.add(map);
        map = new HashMap<>();
        map.put("name","湿度");
        map.put("number","47");
        data.add(map);
        map = new HashMap<>();
        map.put("name","光照");
        map.put("number","30");
        data.add(map);
        map = new HashMap<>();
        map.put("name","CQ2");
        map.put("number","12");
        data.add(map);
        map = new HashMap<>();
        map.put("name","PM2.5");
        map.put("number","2.3");
        data.add(map);
        map = new HashMap<>();
        map.put("name","道路状况");
        map.put("number","良好");
        data.add(map);
    }
}

BaseExpandableListAdapter

因为可展开式的listview需要每个参数都不一样，所以不需要数据类，可以直接将参数传导进入适配器，主要方法有两个

适配器方法

package com.phc.expandablelistview;
   
import android.content.Context;
import android.content.Intent;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.BaseExpandableListAdapter;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
   
import java.util.List;
import java.util.Map;
   
import javax.xml.namespace.QName;
   
/**
 * @author PengHaiChen
 */
public class expandableAdapter extends BaseExpandableListAdapter {
    //这书需要传递你进来的参数类型
    List <Map<String,Object>> anime;
    //创建二维数组
    String[][] character;
    //创建上下文关系
    Context context;
   
    //构造方法用于传递参数
    public expandableAdapter(List<Map<String, Object>> anime, String[][] character, Context context) {
        this.anime = anime;
        this.character = character;
        this.context = context;
        Log.d("hello" ,"expandableAdapter"+character.toString());
    }
   
    //组件类
    public  class module{
        ImageView manga_image;
        TextView manga_name,manga_time,manga_faction,figure_name;
   
    }
   
   
    //父布局数量
    @Override
    public int getGroupCount() {
        //返回集合的长度
        return anime.size();
    }
   
    //子项目数量
    @Override
    public int getChildrenCount(int groupPosition) {
        //返回二维数组的长度
        return character[groupPosition].length;
    }
   
    //父布局根据位置获得对象
    @Override
    public Object getGroup(int groupPosition) {
        return anime.get(groupPosition);
    }
   
    //子布局根据位置获得对象
    @Override
    public Object getChild(int groupPosition, int childPosition) {
        return character[groupPosition][childPosition];
    }
    //获取父布局id
    @Override
    public long getGroupId(int groupPosition) {
        return groupPosition;
    }
//    获取子布局id
    @Override
    public long getChildId(int groupPosition, int childPosition) {
        return childPosition;
    }
    //是否有稳定的id
    @Override
    public boolean hasStableIds() {
        return true;
    }
    //适配父布局
    @Override
    public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
        //如果视图是空的
        if (convertView==null){
//            给一个视图
            convertView= LayoutInflater.from(context).inflate(R.layout.expandable_listview_son,null);
        }
        //创建组件对象
        module md=new module();
        //绑定组件
        md.manga_image=(ImageView) convertView.findViewById(R.id.mangaImage);
        md.manga_name=(TextView)convertView.findViewById(R.id.mangaName);
        md.manga_time=(TextView)convertView.findViewById(R.id.mangaTime);
        md.manga_faction=(TextView)convertView.findViewById(R.id.mangaFaction);
   
           
        //设置元素内容 groupPosition代表位置
        md.manga_image.setImageResource((Integer)anime.get(groupPosition).get("manga_image"));
        md.manga_name.setText(anime.get(groupPosition).get("manga_name").toString());
        md.manga_time.setText(anime.get(groupPosition).get("manga_time").toString());
        md.manga_faction.setText(anime.get(groupPosition).get("manga_faction").toString());
        //设置一下缓冲区
        convertView.setTag(md);
        return convertView;
    }
    //设置子视图
    @Override
    public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
        if (convertView==null){
            convertView=LayoutInflater.from(context).inflate(R.layout.expandable_listview_content,null);
        }
        //调用组件对象
        module md=new module();
        //绑定组件
        md.figure_name=(TextView)convertView.findViewById(R.id.figureName);
        //给组件参数
        md.figure_name.setText(character[groupPosition][childPosition]);
        return convertView;
    }
   
    @Override
    public boolean isChildSelectable(int groupPosition, int childPosition) {
        return true;
    }
   
   
   
}

调用适配器

package com.phc.expandablelistview;
      
import androidx.appcompat.app.AppCompatActivity;
      
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ExpandableListView;
import android.widget.Toast;
      
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
      
public class MainActivity extends AppCompatActivity {
      
    //创建自定义适配器对象
    expandableAdapter expandableAdapterView;
    //创建展开清单对象
    ExpandableListView expandableListView;
    //创建集合 用于保存数据
    List<Map<String,Object>> data;
    //添加番剧图片
    int [] manga_image={R.drawable.daytodat,R.drawable.dororo,R.drawable.jojo,R.drawable.klk,R.drawable.spiritdie};
    //添加数据,番剧名字
    String[] manga_name={"日常","多罗罗","jojo的奇妙冒险","斩服少女","鬼灭之刃"};
    //添加番剧时间
    String[] manga_time={"2020年2月2号","1999年9月9号","2013年3月3号","2014年4月4号","2020年1月1号"};
    //番剧评分
    String[] manga_faction={"4.8","4.7","5.0","5.0","4.6"};
    //番剧人员表
    String [][] character;
      
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
      
        //绑定ExpandableListView组件
        expandableListView=(ExpandableListView) findViewById(R.id.expandablelistview);
        //调用添加数据的方法
        init_data();
        //注入适配器对象
        expandableAdapterView=new expandableAdapter(data,character,this);
        //将自定义适配器放入组件中
        expandableListView.setAdapter(expandableAdapterView);
        //设置点击事件
        expandableListView.setOnChildClickListener(new ExpandableListView.OnChildClickListener(){
            //重写
            @Override
            public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id) {
                String animeTips=data.get(groupPosition).get("manga_name")+","+character[groupPosition][childPosition];
                Toast.makeText(MainActivity.this, "您选择的人物是是"+animeTips, Toast.LENGTH_SHORT).show();
                return false;
            }
        });
      
      
    }
    //添加数据的方法
    void init_data(){
        //注入Arraylist集合对象
        data=new ArrayList<>();
        //创建map对象
        Map map;
        //循环添加数据
        for (int i = 0; i < manga_name.length; i++) {
            map=new HashMap<String,Object>();
            map.put("manga_image",manga_image[i]);
            map.put("manga_name",manga_name[i]);
            map.put("manga_time",manga_time[i]);
            map.put("manga_faction",manga_faction[i]);
            //将map中的数据转存在lit中
            data.add(map);
        }
        //添加人员信息
        character=new String[][]\{\{"sakamoto","博士","名乃","麻衣","美绪","祐子"},{"多罗罗","百鬼丸","宝多丸","和尚"},{"波鲁纳雷夫","乔瑟夫乔斯达","dio","空条承太郎"},{"流缠子","鲜血","鬼龙院罗晓"},{"弥豆子","碳治郎","虫柱","无惨"\}\};
    }
}
        

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