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它已经上市一个月了，但 Android 3.0 的生态环境却没有显示出应有的活力，至今只有约 50 款专用软件上架

移动开发者 Justin Williams 在接受《连线》采访时说：“当年苹果的做法很明智，在 iPad 推出之前几个月就放出了开发工具。相比之下，Google 的开发者只是在 XOOM 发售之前几天才拿到开发工具。”所以在 iPad 发售时，商店里已经有了 1000 个专用软件。当 XOOM 发售时，这个数字是 15 。

还有另外一个原因导致开发者的热情不足，就是 Google 只把系统代码开放给了几个大厂商，例如摩托罗拉，三星，HTC 。大多数设备制造商和开发者根本接触不到 Android 3.0 的代码和技术细节，所以拖累了软件的开发进度

Renderscript is a key new Honeycomb feature which we haven’t yet discussed in much detail

Renderscript is a new API targeted at high-performance 3D rendering and compute operations. The goal of Renderscript is to bring a lower level, higher performance API to Android developers. The target audience is the set of developers looking to maximize the performance of their applications and are comfortable working closer to the metal to achieve this

Renderscript has been used in the creation of the new visually-rich YouTube and Books apps. It is the API used in the live wallpapers shipping with the first Honeycomb tablets.

For completeness we really should handle the possibility of the task getting cancelled. This can happen when the user navigates away from the app and the task is killed before its completed. This will cause the onPostExecute() method to not be called and so the onRefreshComplete() method won’t be called. Depending on how the user navigates through the app, they could return to this activity without going through the complete onCreate() lifecycle, and you’ll end up with the screen still showing the “loading” progress message in the header. This is common when using tabs between multiple ListViews. Also, the documented best practices for implementing an AsyncTask says that in long running background work you should periodically check if the task has been cancelled and try to gracefully quit your work and exit. So let’s get all of that in there.