PopupWindow

 View root = View.inflate(MainActivity.this,R.layout.popwindow, null);
                //创建对象
                PopupWindow popupWindow = new PopupWindow(root,80,320);
                //点击外部可消失
                popupWindow.setBackgroundDrawable(new ColorDrawable());
                popupWindow.setOutsideTouchable(true);
                //获取焦点
                popupWindow.setFocusable(true);
                //设置位置
                popupWindow.showAsDropDown(imageview2);