光标未正确加载到listview?

我正在做简单的listview。我想加载联系人姓名,当我单击listview的项目时,我想将BackgroundColor设置为蓝色。但我有3个问题。首先,我的光标无法正确加载到listview。这是重复你自己。第二个问题是;当我单击listview中的任何项目时,我的listview正在绘制多个项目。第三个是:当我点击最后一个项目时,我的程序出现异常。如何始终正确地将名称加载到listview?我该怎么修`

public class display extends AppCompatActivity {
ListView lv ;
    Button select;
    String phoneNumber;

    ArrayList <String> aa= new ArrayList<String>();





    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        lv = (ListView)findViewById(R.id.lv);
        select = (Button) findViewById(R.id.button1);
        getNumber(this.getContentResolver());}

    public void getNumber(ContentResolver contentResolver) {
        Cursor phones = contentResolver.query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null,null,null, null);
        while (phones.moveToNext())
        {
            String name=phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));
            phoneNumber = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
            System.out.println(".................."+phoneNumber);
            aa.add(name);
        }
        phones.close();// close cursor
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
                android.R.layout.simple_selectable_list_item,aa);
        lv.setAdapter(adapter);

    lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            parent.getChildAt(position).setBackgroundColor(Color.BLUE);
        }
    });
    }

}

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

        android:layout_above="@+id/button1" />

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:text="Select" />

</RelativeLayout>