private PopupWindow mPopupWindow;  //popup window 一般popuowindow 要都个显示view,本例子中view模拟菜单.

private View mMenu;                //popup window 里的view

mMenu.setFocusableInTouchMode(true);
mMenu.setOnKeyListener(this);
mMenu.setOnTouchListener(this);

mPopupWindow.setFocusable(true);
mPopupWindow.setOutsideTouchable(true);

@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;

    }

　　　　　/*

         * 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和点popwindow外面关闭popwindow,

         */

        mPopupWindow.setBackgroundDrawable(new ColorDrawable(-00000));//不支持menu键

        mPopupWindow.setFocusable(true);

        mPopupWindow.setOutsideTouchable(true);