PopupWindow 点击空白处 消失

[code]View view = LayoutInflater.from(context).inflate(R.layout.group_manager_pop, null);
                final PopupWindow pop = new PopupWindow(view, LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
                pop.setBackgroundDrawable(new BitmapDrawable());   

                pop.setFocusable(true);   
                pop.setOutsideTouchable(true); 
                view.findViewById(R.id.groupManText).setOnClickListener(new OnClickListener() {   

                    @Override 
                    public void onClick(View v) {
                        Toast.makeText(context, "", Toast.LENGTH_SHORT).show();
                        if(pop.isShowing()){   
                            pop.dismiss();   
                        } 
                    }   
                }); 

                pop.showAsDropDown(v);
                pop.update();