adt20新建项目Android Support library not installed问题

写道

This template depends on the Android Support library, which is either not installed, or the
template depends on a more recent version than the one you hava installed.
http://developer.android.com/tools/extras/support-library.html

Required version: 8
Installed version: Not installed

You can install or upgrade it by clicking the Install button below, or alternatively, you can
install it outside of Eclipse with the SDK Manager, the click on "Check Again" to proceed.

两个按钮：Install/Upgrade Check Again

按照提示安装升级了一下，再次Check Again， 还是这个错误提示。

写道

解决方案：
进入\extras\android之后没有support文件夹但是有一个compatibility文件夹，新建support文件夹，将compatibility里面的东西复制到support里面。新建一个项目OK。如果compatibility文件夹没有的话，有可能就在\extras的同级目录下有一个android-compatibility文件夹，进入\extras\android\android-新建support文件夹，将compatibility里面的东西复制到support里面。最好重启一下，已保证新的文件生效，新建一个项目OK。