<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:orientation="vertical"     android:gravity="center_horizontal"    android:background="#B6A8D9">    <ImageView        android:id="@+id/imageView1"        android:layout_width="wrap_content"        android:layout_height="240dp"        android:src="@drawable/a" />        <Button        android:id="@+id/close"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="关闭" /></LinearLayout>

<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:orientation="vertical"     android:gravity="center_horizontal">    <Button        android:id="@+id/bn"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="弹出Popup窗口" /></LinearLayout>

package com.example.popupwindow;import android.app.Activity;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.PopupWindow;public class MainActivity extends Activity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        //装载R.Layout.popup对应的界面布局        View root=this.getLayoutInflater().inflate(R.layout.popup, null);        //创建PopupWindow对象        final PopupWindow popup=new PopupWindow(root,280,280);        Button button=(Button) findViewById(R.id.bn);        button.setOnClickListener(new  OnClickListener(){            @Override            public void onClick(View v) {                //下拉方式显示(按钮下方)                popup.showAsDropDown(v);                //设置指定位置                //popup.showAtLocation(findViewById(R.id.bn), Gravity.CENTER, 20, 20);            }                    });        //获取PopupWindow中的关闭按钮        root.findViewById(R.id.close).setOnClickListener(new OnClickListener(){            @Override            public void onClick(View v) {                popup.dismiss();            }                    });    }    }