When Android Studio imports the project, it has been stuck in the Building gradle project info step, mainly because of the result of being walled.
Solution:
1. Find an AS project that you can run before
2. Open the /gradle/wrapper/gradle-wrapper.properties file of the project
3. Copy the last line of distributionUrl, for example: distributionUrl=https\:// services.gradle.org/distributions/gradle-2.8-all.zip, replace the gradle-wrapper.properties file in the project you want to import.
4. Restart Android Studio and re-import the project.