在android中的listview中添加图像和子项

Question

我初学到android nm tryin显示列表视图我会有一个图像，项目n子项目（childitem）..我试过但我无法查看图像和子项目列表..这里是我的代码： -

activity_main： -

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
tools:context=".MainActivity">

<TextView
    android:id="@+id/textview"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" />

<ListView
    android:id="@+id/listview"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"/>

listview_layout： -

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent">

<ImageView
    android:id="@+id/flag"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:contentDescription="@string/hello"
    android:paddingTop="10dp"
    android:paddingRight="10dp"
    android:paddingBottom="10dp"

    />

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    >

    <TextView
        android:id="@+id/txt"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="15dp"
        />

    <TextView
        android:id="@+id/cur"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="10dp"
        />

</LinearLayout>

MainActivity： -

public class MainActivity extends Activity {

// Array of strings storing country names
String[] countries = new String[] {
        "India",
        "Pakistan",
        "Sri Lanka",
        "China",
        "Bangladesh",
        "Nepal",
        "Afghanistan",
        "North Korea",
        "South Korea",
        "Japan"
};

// Array of integers points to images stored in /res/drawable-ldpi/
int[] flags = new int[]{
        R.drawable.india,
        R.drawable.pakistan,
        R.drawable.srilanka,
        R.drawable.china,
        R.drawable.bangladesh,
        R.drawable.nepal,
        R.drawable.afghanistan,
        R.drawable.nkorea,
        R.drawable.skorea,
        R.drawable.japan
};

// Array of strings to store currencies
String[] currency = new String[]{
        "Indian Rupee",
        "Pakistani Rupee",
        "Sri Lankan Rupee",
        "Renminbi",
        "Bangladeshi Taka",
        "Nepalese Rupee",
        "Afghani",
        "North Korean Won",
        "South Korean Won",
        "Japanese Yen"
};


/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // Each row in the list stores country name, currency and flag
    List<HashMap<String,String>> aList = new ArrayList<HashMap<String,String>>();

    for(int i=0;i<10;i++){
        HashMap<String, String> hm = new HashMap<String,String>();
        hm.put("txt", "Country : " + countries[i]);
        hm.put("cur","Currency : " + currency[i]);
        hm.put("flag", Integer.toString(flags[i]) );
        aList.add(hm);
    }

    // Keys used in Hashmap
    String[] from = { "flag","txt","cur" };

    // Ids of views in listview_layout
    int[] to = { R.id.listview,R.id.txt,R.id.cur};

    // Instantiating an adapter to store each items
    // R.layout.listview_layout defines the layout of each item
    SimpleAdapter adapter = new SimpleAdapter(getBaseContext(), aList, R.layout.listview_layout, from, to);

    // Getting a reference to listview of main.xml layout file
    ListView listView = ( ListView ) findViewById(R.id.listview);

    // Setting the adapter to the listView
    listView.setAdapter(adapter);

    // Item Click Listener for the listview
    OnItemClickListener itemClickListener = new OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View container, int position, long id) {
            // Getting the Container Layout of the ListView
            LinearLayout linearLayoutParent = (LinearLayout) container;

            // Getting the inner Linear Layout
            LinearLayout linearLayoutChild = (LinearLayout ) linearLayoutParent.getChildAt(1);

            // Getting the Country TextView
            TextView tvCountry = (TextView) linearLayoutChild.getChildAt(0);

            Toast.makeText(getBaseContext(), tvCountry.getText().toString(), Toast.LENGTH_SHORT).show();
        }
    };

    // Setting the item click listener for the listview
    listView.setOnItemClickListener(itemClickListener);
}

在输出中，listview只显示国家名称..图像和货币值不显示..我错过了什么？