if (null == changePopupWindow) {
            LayoutInflater inflater = LayoutInflater.from(this);
            View popWindow = inflater.inflate(R.layout.pop_custm_recept_arreas,
                    null);
            arreasGroup = (RadioGroup) popWindow
                    .findViewById(R.id.pop_arreas_group);
            arreasGroup.setOnCheckedChangeListener(this
 
);

            changePopupWindow = new PopupWindow(popWindow,
                    ViewGroup.LayoutParams.WRAP_CONTENT,
                    ViewGroup.LayoutParams.WRAP_CONTENT);
            // 設定popwindow可觸控
            changePopupWindow.setFocusable(false);
            // 設定pop外的區域是否可觸控
            changePopupWindow.setOutsideTouchable(true
 
);
            // 例項化一個ColorDrawable顏色為半透明
            ColorDrawable dw = new ColorDrawable(0xb0000000);
            // 設定pop彈出窗體的背景
            changePopupWindow.setBackgroundDrawable(dw);
            backgroundAlpaha(CustomerReceptDestActivity.this, 0.5f);

            // 設定popWindow的顯示和消失動畫
            changePopupWindow.setAnimationStyle(R.style.mypopup_anim_style);
            // 當點選取消的時候，pw消失
 

            popWindow.findViewById(R.id.pop_custom_pay_cancel_submit)
                    .setOnClickListener(new OnClickListener() {

                        @Override
                        public void onClick(View arg0) {
                            changePopupWindow.dismiss();

                        }
                    });
            changePopupWindow.setOnDismissListener(new OnDismissListener() {
                @Override
                public void onDismiss() {
                    backgroundAlpaha(CustomerReceptDestActivity.this, 1.0f);
                }
            });

        }
        ColorDrawable dw = new ColorDrawable(0xb0000000);
        changePopupWindow.setBackgroundDrawable(dw);
        backgroundAlpaha(CustomerReceptDestActivity.this, 0.5f);
        changePopupWindow.showAtLocation(mainLayout, Gravity.CENTER, 0, 0);
    }

    /**
     * 設定新增螢幕的背景透明度
     * **/
    public void backgroundAlpaha(Activity context, float bgAlpha) {
        WindowManager.LayoutParams lp = context.getWindow().getAttributes();
        lp.alpha = bgAlpha;
        context.getWindow()
                .addFlags(WindowManager.LayoutParams.FLAG_DIM_BEHIND);
        context.getWindow().setAttributes(lp);
    }