pop

package com.example.hellopopupwindow;

import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnTouchListener;
import android.view.ViewGroup.LayoutParams;
import android.widget.Button;
import android.widget.PopupWindow;
import android.widget.Toast;

public class MainActivity extends Activity {

    private Context mContext = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mContext = this;

        Button button = (Button) findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View view) {

                showPopupWindow(view);
            }
        });
    }

    private void showPopupWindow(View view) {

        // 一个自定义的布局，作为显示的内容
        View contentView = LayoutInflater.from(mContext).inflate(
                R.layout.pop_window, null);
        // 设置按钮的点击事件
        Button button = (Button) contentView.findViewById(R.id.button1);
        button.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                Toast.makeText(mContext, "button is pressed",
                        Toast.LENGTH_SHORT).show();
            }
        });

        final PopupWindow popupWindow = new PopupWindow(contentView,
                LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT, true);

        popupWindow.setTouchable(true);

        popupWindow.setTouchInterceptor(new OnTouchListener() {

            @Override
            public boolean onTouch(View v, MotionEvent event) {

                Log.i("mengdd", "onTouch : ");

                return false;
                // 这里如果返回true的话，touch事件将被拦截
                // 拦截后 PopupWindow的onTouchEvent不被调用，这样点击外部区域无法dismiss
            }
        });

        // 如果不设置PopupWindow的背景，无论是点击外部区域还是Back键都无法dismiss弹框
        // 我觉得这里是API的一个bug
        popupWindow.setBackgroundDrawable(getResources().getDrawable(
                R.drawable.selectmenu_bg_downward));

        // 设置好参数之后再show
        popupWindow.showAsDropDown(view);

    }

}

<?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:background="#FFBBFFBB"
    android:orientation="vertical" >

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:padding="10dp"
        android:text="Hello My Window"
        android:textSize="20sp" />

    <Button
        android:id="@+id/button1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:padding="10dp"
        android:text="Button"
        android:textSize="20sp" />

</LinearLayout>