How to open an existing Flutter Project in Android Studio
Install Flutter plugin for Android studio: https://flutter.io/get-started/editor/
Open Android Studio
Open existing Android Studio project by using one of below methods:
EASIEST WAY: Drag your project folder and drop to Android Studio.
Other ways:
What works for me was to open existing Android Studio project like mentioned above, and then go to menu
Tools -> Flutter -> Flutter Clean
Then configuration window will open and ask you to locate flutter sdk. After locating the sdk, click OK and then the flutter functions will be available (Pub buttons, runs menu). After that you can proceed to get the dependencies (pub get).
It's basically cleaning the project folder of previous setting(s) which might conflicting with the system (android studio). But that won't happen if you get the project from source repository because all of the junk files wont be in the project folder.
The quickest way on macOS is
open -a Android\ Studio android when you are in the root project directory.
Alternatively, if you use the jetbrains toolbox, you can enable "Shell Scripts" in its settings. This will create a binary in the folder of your choice, so you have to add this folder to your PATH. Then, you can use studio . inside the Android folder, or studio android in the flutter project. The benefit of this, is it also works with other Jetbrains products (e.g. charm project_dir or clion project_dir. Unfortunately this method glitches out (for pycharm at least).