I have developed the UI and flows for an android app on Sketch 3. Now, I am developing that app. So, is there any way to directly exports the layouts or even individual assets to Android Studio?
There many plugins for sketch .
e.g You have to install this plugin for sketch 3 see link
Installation
The actual location of your Sketch plugins directory will vary. To open it just click on the Reveal Plugins Folder under the Plugins menu in sketch.
Run following command after going to the sketch plugins folder:
git clone git@github.com:GeertWille/sketch-export-assets.git sketch-export-assets.sketchplugin
OR
Create a new directory called sketch-export-assets.sketchplugin and place the content of this repository in it.
Once you have checked out the plugin repository into the relevant directory, you'll find the plugin functions under the Plugins menu in Sketch.
来源：https://stackoverflow.com/questions/31217933/how-to-import-ui-assets-or-layouts-from-sketch-3-directly-to-android-studio