This version of the pager is best for use when there are a handful of typically more static fragments to be paged through, such as a set of tabs. The fragment of each page the user visits will be kept in memory, though its view hierarchy may be destroyed when not visible. This can result in using a significant amount of memory since fragment instances can hold on to an arbitrary amount of state. For larger sets of pages, consider FragmentStatePagerAdapter.
中的pager在这里是什么意思啊
连接地址:https://developer.android.google.cn/reference/android/support/v13/app/FragmentPagerAdapter.html