Simple Problem Causes Huge Impact in the New Android Studio for macOS
Yesterday night I updated my AndroidStudio from 3.5.x to 3.6.1. AndroidStudio 3.6.1 brought some new features like Visual Layout Editor, which I would like to try.

Everything seems working fine but I cannot deploy my app anymore, also a very simple app, to my Android Virtual Devices (AVD). I cannot see my Android app starts in my AVD. Gradle and the Android project are green but still my app did not show up. I could not see any problems until I see this red message:
Error while waiting for device: Unable to locate adb (Android Debug Bridge)
So, it was the time to search for an answer in Internet. I found some questions and answers:
- “Unable to locate adb” using Android Studio and Error: Unable to locate adb within SDK in Android Studio
- How to Solve Unable to Locate ADB in Android Studio
… and many other articles but none of them show me a way to correct this problem on macOS.
As all the articles said, the problem is actually quite simple:
The Platform Tools “platform-tools” with its “adb” were put in the wrong place, so Android Studio cannot find them.
After trying some hours I could find this solution for my macOS:
(1) This is how the directory structure of your Android SDK on your macOS looks like:

The problem area is the directory platform-tools.
(2) As I took a look under the platform-tools I saw that I have following structure:

So it seems that the installation of the platform-tools make a wrong structure by duplicating platform-tools/platform-tools.
(3) My solution was just to move the whole content of platform-tools/platform-tools/* to platform-tools/*. That’s it!
After moving the content of platform-tools to the right place, everything is working fine and I could deploy my Android app to my AVD just like before the update.