Android Studio 2.2 Preview 3 发布了，该版本新增一些新特性，以及修复 Preview 2 中发现的 Bugs。
以下是该版本值得关注的内容：
Espresso Test Recorder
Demo of the Espresso Test Recorder shown at IO is now included in Preview 3
Constraint Layout
ConstraintLayout editor:
New toolbar UI
Pan & zoom widget in the inspector
Better auto-inference
Databinding support in the layout editor
ConstraintLayout:
Fixed padding bug
Various bug fixes (design mode positioning, etc.)
Images support:
Photoshop viewer integrated in Android Studio
Convert Photoshop files to Vector Drawable
完整发布说明，点击这里查看。
下载地址：https://sites.google.com/a/android.com/tools/download/studio