<RelativeLayout 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"
tools:context="com.example.spin.MainActivity" >
<EditText
android:id="@+id/et_editText"
android:layout_width="250dp"
android:layout_height="50dp"
android:layout_centerHorizontal="true"
android:layout_marginTop="10dp"
android:text="@string/hello_world" />
<ImageView 
android:id="@+id/down"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/down_arrow"
android:layout_alignRight="@id/et_editText"
android:layout_marginTop="20dp"
android:clickable="true"/>

</RelativeLayout>

<?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"
android:gravity="center_vertical"
android:orientation="horizontal" >

<ImageView 
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/user"/>
<TextView 
android:id="@+id/tv_list_item"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center_horizontal"
android:text="100000000"/>
<ImageView
android:id="@+id/delete"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/delete"/>

</LinearLayout>

public class MainActivity extends ActionBarActivity {

private EditText et_editText;//編輯框
private ImageView down;//下拉按鈕
private ListView listView;
private List<String> numList;
private PopupWindow popWin; 
private Boolean isDown=false;//判斷彈窗是否顯示 
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main); 
et_editText = (EditText) findViewById(R.id.et_editText);
down = (ImageView) findViewById(R.id.down);
//創(chuàng)建集合 儲存號碼
numList = new ArrayList<String>();
for(int i=0;i<20;i++){
numList.add("100000000"+i);
} 
initListView();
//對下拉按鈕設(shè)置監(jiān)聽 當(dāng)進(jìn)行點(diǎn)擊時(shí) 彈出popWin
down.setOnClickListener(new OnClickListener() { 
@Override
public void onClick(View v) {
if(!isDown){
//定義一個(gè)popupWindow
popWin=new PopupWindow(MainActivity.this);
popWin.setWidth(et_editText.getWidth());//設(shè)置寬度 和編輯框的寬度相同
popWin.setHeight(200); //設(shè)置高度
//為popWin填充內(nèi)容
popWin.setContentView(listView);
//點(diǎn)擊popWin區(qū)域之外 自動關(guān)閉popWin
popWin.setOutsideTouchable(true);
/**
* 設(shè)置彈出窗口顯示的位置
* 參數(shù)一:相對于參數(shù)的位置進(jìn)行顯示 即在編輯框的下面顯示
* 參數(shù)二 三:x y軸的偏移量
*/
popWin.showAsDropDown(et_editText, 0, 0);
isDown=true;
}else{
popWin.dismiss();
isDown=false;
}
}
});
}
//點(diǎn)擊返回按鈕
@Override
public void onBackPressed() {
/**
* 當(dāng)用戶點(diǎn)擊返回按鈕時(shí) 是整個(gè)activity退出 而且給人的感覺是直接退出 窗口可能還是顯示狀態(tài),
為了避免內(nèi)存泄露,先關(guān)閉彈窗 
* 
* 當(dāng)點(diǎn)擊返回按鈕時(shí) 如果窗口存在且正在顯示 則關(guān)閉窗口
*/
if(popWin!=null&&popWin.isShowing()){
popWin.dismiss();
}
super.onBackPressed();
}
private void initListView() {
listView = new ListView(this);
//設(shè)置listView的背景
listView.setBackgroundResource(R.drawable.listview_background);
//設(shè)置條目之間的分割線及滾動條不可見
listView.setDivider(null);
listView.setVerticalScrollBarEnabled(false);
//設(shè)置適配器
listView.setAdapter(new MyListAdapter());
}
private class MyListAdapter extends BaseAdapter{
@Override
public int getCount() {
return numList==null?0:numList.size();
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if(convertView==null){
convertView=View.inflate(getApplicationContext(), R.layout.list_item, null);
holder=new ViewHolder();
holder.tvNum=(TextView) convertView.findViewById(R.id.tv_list_item);
holder.delete=(ImageView) convertView.findViewById(R.id.delete);
convertView.setTag(holder);
}else{
holder=(ViewHolder) convertView.getTag();
}
holder.tvNum.setText(numList.get(position));
//對刪除按鈕設(shè)置監(jiān)聽事件
holder.delete.setOnClickListener(new OnClickListener() { 
@Override
public void onClick(View v) {
//當(dāng)點(diǎn)擊刪除按鈕時(shí) 刪除條目
numList.remove(position);
//刷新ListView
MyListAdapter.this.notifyDataSetChanged();
}
});
//對條目設(shè)置監(jiān)聽事件 點(diǎn)擊條目后 將num設(shè)置到編輯框中
convertView.setOnClickListener(new OnClickListener() { 
@Override
public void onClick(View v) {
//點(diǎn)擊條目后 將num設(shè)置到編輯框中
et_editText.setText(numList.get(position));
popWin.dismiss();
}
});
return convertView;
}
@Override
public Object getItem(int position) {
return null;
}
@Override
public long getItemId(int position) {
return 0;
}
}

private class ViewHolder {
TextView tvNum;
ImageView delete;
}
}