<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"    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" >    <EditText        android:id="@+id/et"        android:layout_width="200dp"        android:layout_height="wrap_content"        android:inputType="text" />    <ImageView        android:id="@+id/iv"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_alignRight="@id/et"        android:src="@drawable/down_arrow" /></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:src="@drawable/user" />    <TextView        android:layout_width="0dp"        android:layout_height="wrap_content"        android:layout_weight="1"        android:gravity="center"        android:text="内容"         android:id="@+id/tv_listitem_content"/>    <ImageView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:src="@drawable/delete"         android:id="@+id/iv_listitem_delete"/></LinearLayout>

package com.gnnuit.dropdownlist;import java.util.ArrayList;import java.util.List;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.EditText;import android.widget.ImageView;import android.widget.ListView;import android.widget.PopupWindow;import android.widget.TextView;import android.app.Activity;public class MainActivity extends Activity {    private ImageView iv;    private PopupWindow popupWindow;    private ListView lv;    private EditText et;    private List<String> strs = new ArrayList<String>();    private MyAdapter adapter;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        initListView();// 初始化ListView        et = (EditText) findViewById(R.id.et);        iv = (ImageView) findViewById(R.id.iv);        iv.setOnClickListener(new OnClickListener() {            @Override            public void onClick(View v) {                if (popupWindow == null) {                    popupWindow = new PopupWindow(MainActivity.this);                    popupWindow.setContentView(lv);                    // PopupWindow必须设置高度和宽度                    popupWindow.setWidth(et.getWidth()); // 设置宽度                    popupWindow.setHeight(200); // 设置popWin 高度                    popupWindow.showAsDropDown(et, 0, 0);                    popupWindow.setOutsideTouchable(true);// 设置后点击其他位置PopupWindow将消失                } else if (popupWindow != null && popupWindow.isShowing()) {                    popupWindow.dismiss();                } else {                    popupWindow.showAsDropDown(et);                }            }        });    }    /**     * 初始化ListView     */    private void initListView() {        for (int i = 0; i < 10; i++) {            strs.add("第" + i + "条记录");        }        lv = new ListView(this);        if (adapter == null) {            adapter = new MyAdapter();            lv.setAdapter(adapter);        } else {            adapter.notifyDataSetChanged();        }        lv.setBackgroundResource(R.drawable.listview_background);        lv.setDividerHeight(2);        lv.setVerticalScrollBarEnabled(false);    }    private class MyAdapter extends BaseAdapter {        @Override        public int getCount() {            return strs.size();        }        @Override        public Object getItem(int position) {            return strs.get(position);        }        @Override        public long getItemId(int position) {            return position;        }        @Override        public View getView(final int position, View convertView, ViewGroup parent) {            View view;            ViewHolder holder;            if (convertView == null) {                view = View.inflate(MainActivity.this, R.layout.list_item, null);                holder = new ViewHolder();                holder.iv = (ImageView) view.findViewById(R.id.iv_listitem_delete);                holder.tv = (TextView) view.findViewById(R.id.tv_listitem_content);                view.setTag(holder);            } else {                view = convertView;                holder = (ViewHolder) view.getTag();            }            holder.tv.setText(strs.get(position));            holder.tv.setOnClickListener(new OnClickListener() {                @Override                public void onClick(View v) {                    et.setText(strs.get(position));                    popupWindow.dismiss();                }            });            holder.iv.setOnClickListener(new OnClickListener() {                @Override                public void onClick(View v) {                    // 从List中移除                    strs.remove(position);                    // 更新ListView                    adapter.notifyDataSetChanged();                }            });            return view;        }    }    private class ViewHolder {        private TextView tv;        private ImageView iv;    }}