Android Studio 2.2 Preview 5 发布，此版本包括了大量的bug修复。

• Performance: We fixed two big memory leaks -- one related to Gradle sync and the other related to layout rendering; both should help significantly with memory usage. We also improved the locking behavior of layout XML preview so it shouldn't cause the editor to lag when typing during background layout preview rendering.

• Instant Run: A number of important bug fixes which should help with performance and correctness:

• Fixed a bug where assets were not properly packaged

• Disable the small optimization where edits in the main app module skip certain tasks: this was not safe and could lead to some edits missing when running the app

• Fix a bug which meant assets would not be incrementally packaged in alpha4

• No longer crunch PNGs in library dependencies

• Fix bug where updating launcher icons would not trigger an app reinstall

• Layout Editor:

• Auto connect mode is now off by default.

• New constraint layout library version alpha4. 

• There's a lint warning (and quickfix to update) if you're using alpha3 or older. 

• The focus of the update is on layout performance.

• There's also documentation on the various attributes, and code completion should work better with this version in the IDE

• Note: There is an incompatible change in the Guideline class and attributes:  layout_constraintGuide_begin, layout_constraintGuide_end and layout_constraintGuide_Percent

• The resize screen feature has been tweaked visually and should be much faster.

• The screenshot action has been added back to the Context menu, and there is a preference panel in options where you can set the "prefer XML editor for layout files" option as in previous releases.

• Lint icons no longer show up on the design surface by default, but you can turn them back on via options (including from the lint notifications panel.)

• PhotoShop file support: Layers in 16 bit and 32 bit images are now decoded

• Fixed many bugs, including the <include> bug starred by a bunch of users where on Windows, include tags would stop working

• Other: A lot of fixes across the product - in deployment, editor, data binding, C++/CMake/NDK support, lint, Espresso test runner, Firebase, etc.

• Updated platform metadata for Android Nougat (e.g. code completion for context.getSystemService() should return all the valid constants as of N, etc.)

• Fixes for the most common exceptions reported via the crash reporter

详情：Android Studio 2.2 Preview 5 Available