popupwindow的基本應用，點擊外部消失

//自定義佈局
View view=View.inflate(this,R.layout.popup_detail,null);
Button btn_copy= (Button) view.findViewById(R.id.detail_popup_copy);
Button btn_open= (Button) view.findViewById(R.id.detail_popup_open);
Button btn_clear= (Button) view.findViewById(R.id.detail_popup_clear);
Button btn_sendMsg= (Button) view.findViewById(R.id.detail_popup_sendMsg);
btn_copy.setOnClickListener(this);
btn_open.setOnClickListener(this);
btn_clear.setOnClickListener(this);
btn_sendMsg.setOnClickListener(this);

    pop=new PopupWindow(view, DensityUtil.dip2px(this,200), LinearLayout.LayoutParams.WRAP_CONTENT,true);

    pop.setTouchable(true);
    pop.setTouchInterceptor(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            return false;
        }
    });
    pop.setBackgroundDrawable(getResources().getDrawable(R.drawable.popup_bg));
    //pop.setAnimationStyle(R.style.mypopwindow_anim_style);
    pop.showAsDropDown(btn_more,0,0);
    pop.setOnDismissListener(new PopupWindow.OnDismissListener() {
        @Override
        public void onDismiss() {
            //此方法必須重寫，否則點擊外部不能消失
        }
    });