Android -- ListView与ArrayAdapter、SimpleAdapter

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <ListView
        android:id="@+id/lv"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
         />

</LinearLayout>

<?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="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher" />

    <TextView
        android:id="@+id/tv"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

</LinearLayout>

private static String[] names= {"功能1","功能2","功能3","功能4","功能5"};
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        ListView lv = (ListView) findViewById(R.id.lv);
        lv.setAdapter(new ArrayAdapter<String>(this, R.layout.list_item,R.id.tv, names));
    }

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        ListView lv = (ListView) findViewById(R.id.lv);
        List<Map<String,Object>> data = new ArrayList<Map<String,Object>>();

        Map<String,Object> map1 = new HashMap<String, Object>();
        map1.put("nameText", "第1个啦啦啦");
        map1.put("icon", R.drawable.ic_launcher);

        Map<String,Object> map2 = new HashMap<String, Object>();
        map2.put("nameText", "第2个啦啦啦");
        map2.put("icon", R.drawable.info_buse);

        Map<String,Object> map3 = new HashMap<String, Object>();
        map3.put("nameText", "第3个啦啦啦");
        map3.put("icon", R.drawable.info_duijiao);

        Map<String,Object> map4 = new HashMap<String, Object>();
        map4.put("nameText", "第4个啦啦啦");
        map4.put("icon", R.drawable.info_flash);

        data.add(map1);
        data.add(map2);
        data.add(map3);
        data.add(map4);
        
        lv.setAdapter(new SimpleAdapter(this, data, R.layout.list_item, new String[]{"nameText", "icon"},new int[]{R.id.tv,R.id.iv}));
    }