andorid 列表视图 ListView 之BaseAdapter

.xml

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

<ListView xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:id="@+id/lv_2">

</ListView>

.java   //  BaseAdapter

package com.hanqi.application3;

import android.os.Bundle;

import android.support.v7.app.AppCompatActivity;

import android.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import android.widget.BaseAdapter;

import android.widget.ImageView;

import android.widget.ListView;

import android.widget.TextView;

import java.util.ArrayList;

import java.util.List;

public class UIActivity5 extends AppCompatActivity {

    //List<Map<String,Object>> lm;

    List<Food> lf;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_ui5);

        ListView lv_2 = (ListView)findViewById(R.id.lv_2);

        lf= new ArrayList<Food>();

        lf.add(new Food(R.drawable.an1, "内容1","美食1"));

        lf.add(new Food(R.drawable.an2, "内容2", "美食2"));

        lf.add(new Food(R.drawable.an3, "内容3", "美食3"));

        lf.add(new Food(R.drawable.an1, "内容4","美食4"));

        lf.add(new Food(R.drawable.an1, "内容5","美食5"));

        lf.add(new Food(R.drawable.an2, "内容6","美食6"));

        lf.add(new Food(R.drawable.an3, "内容7","美食7"));

        lf.add(new Food(R.drawable.an1, "内容8","美食8"));

        lf.add(new Food(R.drawable.an1, "内容9","美食9"));

        lf.add(new Food(R.drawable.an2, "内容10","美食10"));

        lf.add(new Food(R.drawable.an3, "内容11","美食11"));

        lf.add(new Food(R.drawable.an1, "内容12","美食12"));

        //准备数据源

//        lm = new ArrayList<Map<String,Object>>();

//

//        Map<String, Object> map=new HashMap<String, Object>();

//        map.put("image",R.drawable.an1);

//        map.put("name","美食图片01");

//        map.put("content","看上去很好吃01");

//        lm.add(map);

//

//        map=new HashMap<String, Object>();

//        map.put("image",R.drawable.an2);

//        map.put("name","美食图片02");

//        map.put("content","看上去很好吃02");

//        lm.add(map);

//

//        map=new HashMap<String, Object>();

//        map.put("image",R.drawable.an3);

//        map.put("name","美食图片03");

//        map.put("content","看上去很好吃03");

//        lm.add(map);

        lv_2.setAdapter(new MyBaseAdapter());

    }

    class MyBaseAdapter extends BaseAdapter

    {

        //获取要显示的列表的行数

        @Override

        public int getCount() {

            return lf.size();

        }

        //获取对应下标行

        @Override

        public Object getItem(int position) {

            return lf.get(position);

        }

        //获取对应下标行的id

        @Override

        public long getItemId(int position) {

            return position;

        }

        //给视图适配数据  返回视图

        //position  数据的下标

        // convertView  可重复使用

        //parent  父视图

        @Override

        public View getView(int position, View convertView, ViewGroup parent) {

            //如果 convertView为null  就加载layout文件

            if(convertView == null) {

                //1.获取样式layout文件

                LayoutInflater layoutInflater = getLayoutInflater();

                convertView  = layoutInflater.inflate(R.layout.layout_simple, null);

            }

            //2.数据和layout文件的视图组件进行绑定

            //1)从数据源里获取一行数据

            //Map<String, Object> map = lf.get(position);

            Food food = lf.get(position);

            //2)获取layout文件的视图组件

            ImageView iv_2 = (ImageView)convertView.findViewById(R.id.iv_2);

            TextView  tv_1=(TextView)convertView.findViewById(R.id.tv_1);

            TextView  tv_2=(TextView)convertView.findViewById(R.id.tv_2);

            //3)数据适配

//            iv_2.setImageResource((int)map.get("image"));

//            tv_1.setText(map.get("name").toString());

//            tv_2.setText(map.get("content").toString());

            iv_2.setImageResource(food.getImage());

            tv_1.setText(food.getName());

            tv_2.setText(food.getContent());

            //3.返回视图

            return convertView;

        }

    }

}

layout_simple.xml

<?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="wrap_content">

    <ImageView

        android:layout_width="70dp"

        android:layout_height="70dp"

        android:src="@drawable/an1"

        android:id="@+id/iv_2"/>

    <LinearLayout

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:orientation="vertical"

        android:layout_gravity="center_vertical"

        android:layout_marginLeft="20dp">

        <TextView

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="美食图片"

            android:id="@+id/tv_1"/>

        <TextView

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:text="很好吃的样子"

            android:id="@+id/tv_2"/>

    </LinearLayout>

</LinearLayout>