android中popupwindow的点滴

java类：

package com.tony.PopupWindow;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.app.Activity;
import android.graphics.drawable.ColorDrawable;
import android.os.Bundle;
import android.view.Gravity;
import android.view.MotionEvent;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.Button;
import android.widget.ListView;
import android.widget.PopupWindow;
import android.widget.SimpleAdapter;
import android.widget.Toast;

public class PopupWindowActivity extends Activity {

	private static final String TAG = "PopupWindowActivity";

	private List<Map<String, String>> list = new ArrayList<Map<String, String>>();

	private int state;
	private Button myButton;
	private ListView menulist;
	private View layout;
	private PopupWindow pop;

	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);

		HashMap<String, String> map1 = new HashMap<String, String>();
		map1.put("menuItemName", "系统设置");
		list.add(map1);
		HashMap<String, String> map2 = new HashMap<String, String>();
		map2.put("menuItemName", "自助更新");
		list.add(map2);
		HashMap<String, String> map3 = new HashMap<String, String>();
		map3.put("menuItemName", "关于");
		list.add(map3);
		HashMap<String, String> map4 = new HashMap<String, String>();
		map4.put("menuItemName", "搜索");
		list.add(map4);
		HashMap<String, String> map5 = new HashMap<String, String>();
		map5.put("menuItemName", "退出");
		list.add(map5);

		myButton = (Button) findViewById(R.id.button);

		myButton.setOnClickListener(new View.OnClickListener() {

			@Override
			public void onClick(View v) {
				if (state == 1 && pop.isShowing()) {
					state = 0;
					pop.dismiss();
				} else {
					/***	弹出自定义的菜单		***/
					layout = getLayoutInflater().inflate(R.layout.menu_layout,
							null);
					menulist = (ListView) layout.findViewById(R.id.menulist);
					SimpleAdapter listAdapter = new SimpleAdapter(
							PopupWindowActivity.this, list, R.layout.menu_item,
							new String[] { "menuItemName" },
							new int[] { R.id.menuitem });
					menulist.setAdapter(listAdapter);

					/**
					 * layout							PopupWindow所显示的界面	
					 * myButton.getWidth()				设置PopupWindow宽度
					 * myButton.getHeight() * 3 + 5		设置PopupWindow宽度高度
					 */
					pop = new PopupWindow(
							layout,
							myButton.getWidth(),
							myButton.getHeight() * 3 + 5);

					ColorDrawable cd = new ColorDrawable(-0000);
					pop.setBackgroundDrawable(cd);
					// pop.showAsDropDown(v);

					pop.update();
					pop.setInputMethodMode(PopupWindow.INPUT_METHOD_NEEDED);
					pop.setTouchable(true);	// 设置popupwindow可点击
					pop.setOutsideTouchable(true);	// 设置popupwindow外部可点击
					pop.setFocusable(true);	//获取焦点
					/*设置popupwindow的位置*/
					pop.showAtLocation(layout,
							(Gravity.BOTTOM - myButton.getHeight())
									| Gravity.LEFT, 0, 2 * myButton.getHeight());
					state = 1;
					pop.setTouchInterceptor(new View.OnTouchListener() {
						@Override
						public boolean onTouch(View v, MotionEvent event) {
							/****	如果点击了popupwindow的外部，popupwindow也会消失	****/
							if (event.getAction() == MotionEvent.ACTION_OUTSIDE) {
								pop.dismiss();
								return true; 
							}
							return false;
						}

					});
					/****	点击listview中item的处理	****/
					menulist.setOnItemClickListener(new OnItemClickListener() {

						@Override
						public void onItemClick(AdapterView<?> arg0, View arg1,
								int arg2, long arg3) {
							switch (arg2) {
							case 0:
								Toast.makeText(getApplicationContext(), "系统设置",
										Toast.LENGTH_SHORT).show();
								pop.dismiss();
								break;
							case 1:
								Toast.makeText(getApplicationContext(), "自动更新",
										Toast.LENGTH_SHORT).show();
								pop.dismiss();
								break;
							case 2:
								Toast.makeText(getApplicationContext(), "关于",
										Toast.LENGTH_SHORT).show();
								pop.dismiss();
								break;
							case 3:
								Toast.makeText(getApplicationContext(), "搜索",
										Toast.LENGTH_SHORT).show();
								pop.dismiss();
								break;
							case 4:
								Toast.makeText(getApplicationContext(), "退出",
										Toast.LENGTH_SHORT).show();
								pop.dismiss();
								break;
							}
						}
					});
				}
			}
		});
	}
}

布局文件：

main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <Button
        android:layout_width="100dp "
        android:layout_height="wrap_content"
        android:id="@+id/button"
        android:text="菜单" />

</LinearLayout>

 menu_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:background="@drawable/a2" 
    >

    <ListView
        android:id="@+id/menulist"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" >
    </ListView>

</LinearLayout>

 menu_item.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" >

    <TextView
        android:id="@+id/menuitem"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="15dp"
        android:textColor="#FFFFFF"
        android:textSize="20sp" />

</LinearLayout>

下面是运行的结果：

点击popupwindow会有相应的处理，点击返回键或者是popupwindow外部的区域popupwindow也会消失，这也是很多人想要的效果。

需要强调的一些事儿：

1.PopuWindow 的大小由下面代码控制；

new PopupWindow(view, ViewGroup.LayoutParams.FILL_PARENT,ViewGroup.LayoutParams.WRAP_CONTENT)；

 2.需要顺利让PopUpWindow dimiss（即点击PopuWindow之外的地方此或者back键PopuWindow会消失）；PopUpWindow的背景不能为空。必须在popuWindow.showAsDropDown(v);或者其它的显示PopuWindow方法之前设置它的背景不为空：如下面两行代码：

ColorDrawablecd = new ColorDrawable(-0000);
popu.setBackgroundDrawable(cd);

注意这里设置背景并不会覆盖xml文件定义的背景。

 3.当有popuWindow.setFocusable(false);的时候，说明PopuWindow不能获得焦点，即使设置设置了背景不为空也不能点击外面消失，只能由dismiss()消失，但是外面的View的事件还是可以触发,back键也可以顺利dismiss掉。当设置为popuWindow.setFocusable(true);的时候，加上下面两行设置背景代码，点击外面和Back键才会消失。

ColorDrawable cd = new ColorDrawable(-0000);
pop.setBackgroundDrawable(cd);

 4.这里设置显示PopuWindow之后在外面点击是否有效。如果为false的话，那么点击PopuWindow外面并不会关闭PopuWindow。当然这里很明显只能在Touchable下才能使用。

ColorDrawable cd = new ColorDrawable(-0000);
pop.setBackgroundDrawable(cd);