ListView的应用

 ListView在安卓中是很常用的一个组件之一，那么现在我们做一个水果展示的界面

首先写一个xml文件

<?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"
    android:orientation="horizontal">
    <ListView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/lv"></ListView>

</LinearLayout>

然后再写一个xml文件作为listview的子列表

<?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"
    android:orientation="horizontal">
    <ImageView
        android:layout_width="50dp"
        android:layout_height="50dp"
        android:id="@+id/image"/>
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/fruit_name"
        android:layout_gravity="center"/>

</LinearLayout>

然后是Mainactivity里面

package com.example.mywillstudy;

import android.support.v4.util.ArrayMap;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.Toast;

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

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.layout);
        ListView listView = (ListView)this.findViewById(R.id.lv);
        final List<Map<String,String>> list = new ArrayList<>();
        Map<String, String> map1 = new ArrayMap<>();
        map1.put("id",R.drawable.apple+"");
        map1.put("name","苹果");
        list.add(map1);
        Map<String, String> map2 = new ArrayMap<>();
        map2.put("id",R.drawable.banana+"");
        map2.put("name","香蕉");
        list.add(map2);
        Map<String, String> map3 = new ArrayMap<>();
        map3.put("id",R.drawable.putao+"");
        map3.put("name","葡萄");
        list.add(map3);
        SimpleAdapter adapter = new SimpleAdapter(this,list,R.layout.item,new String[]{"id","name"},new int[]{R.id.image,R.id.fruit_name});
        listView.setAdapter(adapter);
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                Toast.makeText(MainActivity.this,list.get(i).get("name"),Toast.LENGTH_SHORT).show();
            }
        });

    }
}

最后我们可以看到这样的一个可以点击获取水果名的列表框