android 随笔

All View objects have getTag() and setTag() methods. These allow you to
associate an arbitrary object with the widget.What the holder pattern does
is use that "tag" to hold an object that, in turn, holds each of the child
widgets of interest.


android:theme="@android:style/Theme.Dialog"
注意添加这个就可以把activity变为dialog


PopupWindow的使用其为一个特殊的view

A popup window that can be used to display an arbitrary view. The popup windows is a floating container that appears on top of the current activity.