public class CustomActionProvider extends ActionProvider implements

        OnMenuItemClickListener, OnClickListener, OnTouchListener, OnKeyListener {

    private final Context context;// 上下文

    private View actionView;//action view

    private PopupWindow mPopupWindow;//popup window 里有个view,view显示的像个menu

    private View mMenu;                //popup window 里的显示控件

    private void initPopupMenu(){

        LayoutInflater lif = LayoutInflater.from(context);

        mMenu = lif.inflate(R.layout.custom_popup_window, null);

        //不用setBackgroundDrawable的时候必须加这句才能back键和menu键退出

        mMenu.setFocusableInTouchMode(true);

        mMenu.setOnKeyListener(this);

        mMenu.setOnTouchListener(this);

        mPopupWindow = new PopupWindow(mMenu,

                WindowManager.LayoutParams.WRAP_CONTENT,

                WindowManager.LayoutParams.WRAP_CONTENT);

        /*

         * setBackgroundDrawable很重要,没有这个函数 back键和menu键关闭popwindow 很麻烦,

         * 有了它以后,就不用为popwindow内的控件分别设置setOnKeyListener和setOnTouchListener了

         * 可以同时支持back返回和点popwindow外面关闭popwindow,

         */

//        mPopupWindow.setBackgroundDrawable(new ColorDrawable(-00000));

        mPopupWindow.setFocusable(true);

        mPopupWindow.setOutsideTouchable(true);

        mPopupWindow.setAnimationStyle(R.anim.popwindow_anim);

        mMenu.findViewById(R.id.btn1_popup_window).setOnClickListener(this);

        mMenu.findViewById(R.id.btn2_popup_window).setOnClickListener(this);

        mMenu.findViewById(R.id.btn3_popup_window).setOnClickListener(this);

        mMenu.findViewById(R.id.btn4_popup_window).setOnClickListener(this);

        mMenu.findViewById(R.id.btnClose_popup_window).setOnClickListener(this);

    }

    //...

    @Override

    public void onClick(View v) {

        // TODO Auto-generated method stub

        switch (v.getId()) {

        case R.id.btn_action_view_for_costomProvider: {

            mPopupWindow.showAsDropDown(v,-20,10);

        }

            return;

        case R.id.btn4_popup_window:

        case R.id.btn3_popup_window:

        case R.id.btn2_popup_window:

        case R.id.btn1_popup_window:

            Toast.makeText(context, "popup window item clicked",

                    Toast.LENGTH_SHORT).show();

            break;

        case R.id.btnClose_popup_window:

            break;

        }

        mPopupWindow.dismiss();

    }

    @Override

    public boolean onKey(View v, int keyCode, KeyEvent event) {

        // TODO Auto-generated method stub

        switch (keyCode) {

        case KeyEvent.KEYCODE_BACK:

        case KeyEvent.KEYCODE_MENU:

            if (mPopupWindow != null && mPopupWindow.isShowing()) {

                mPopupWindow.dismiss();

            }

            break;

        }

        return true;

    }

    @Override

    public boolean onTouch(View v, MotionEvent event) {

        // TODO Auto-generated method stub

        mPopupWindow.dismiss();

        return false;

    }

}