Google 今天发布了 Android SDK 工具和Eclipse 开发插件 R17 版本，该版本包含很多构建系统、模拟器方面的 bug 修复，同时也引入一些新特性。

特别是在 Windows 和 Mac 虚拟模式下支持 AOSP x86 Android 构建，另外模拟器支持多点触摸的操作。

完整的改进记录如下：

• Added check for Android API calls that require a version of Android higher than the minimum supported version. You can use the new @TargetApiannotation to specify local overrides for conditionally loaded code. For more information, read here.
• Added over 40 new Lint rules for a total of over 80, including checks for performance, XML layouts, manifest and file handling. For a full list read here.
• Added ability to suppress Lint warnings in Java code with the new @SuppressLint annotation, and in XML files with the new tools: namespace prefix and ignore attribute. For more information, read here.
• Improved HTML and XML reporting and Eclipse integration. For more information, read here.

构建系统包括 Eclipse 和 Ant 方面的改进：

• Added strict dependency support for 3rd party Jar files. You can read more information here.
• Added support for custom views with custom attributes in libraries. Layouts using custom attributes must use the namespace URIhttp://schemas.android.com/apk/res-auto instead of the URI that includes the app package name. This URI is replaced with the app specific one at build time.
• Added a feature that allows you to run some code only in debug mode. Builds now generate a class called BuildConfig containing a DEBUG constant that is automatically set according to your build type. You can check the (BuildConfig.DEBUG) constant in your code to run debug-only functions such as outputting debug logs.

模拟器改进：

• Thanks to contributions to AOSP from Intel, the emulator now supports running x86 system images in virtualization mode on Windows and Mac OS X. This allows the emulator running at near native speed. The drivers are available through the SDK Manager. Read more here.
• After adding webcam support and sensor emulation, we are adding experimental support for Multi-Touch input through a tethered Android device. (Read more here)

最后是一些更新的支持库的改进：

• ShareCompat provides easy helper classes for both sending and receiving content for social sharing apps.
• NavUtils and TaskStackBuilder provide cross-version support for implementing the Android Design guidelines for navigating within your app including the action bar’s “Up” button.
• NotificationCompat.Builder provides a compatibility implementation of Android 3.0′s Notification.Builder helper class for creating standardized system notifications.
• A new Library Project adds support for GridLayout back to API level 7 and higher.