Flutter not able to find virtual device

Issue

I have a problem with Flutter. I'm using Android Studio 3.2.1 on Ubuntu 18.04. I am not able to make it find my virtual devices.

When I run flutter doctor, the following output is shown:

$ flutter doctor
Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel master, v0.11.10-pre.3, on Linux, locale en_US.UTF-8)
[✓] Android toolchain - develop for Android devices (Android SDK 28.0.3)
[✓] Android Studio (version 3.2)
[!] Connected device

! Doctor found issues in 1 category.

When I run flutter emulators it finds the device:

$ flutter emulators
1 available emulator:

Nexus_5X_API_28 • Nexus 5X • Google • Nexus 5X API 28

To run an emulator, run 'flutter emulators --launch <emulator id>'.
To create a new emulator, run 'flutter emulators --create [--name xyz]'.

I can then run flutter emulators --launch Nexus_5X_API_28 to start the emulator. It opens as expected.

When I run flutter doctor again, it is still not able to find the device:

    $ flutter doctor
Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel master, v0.11.10-pre.3, on Linux, locale en_US.UTF-8)
[✓] Android toolchain - develop for Android devices (Android SDK 28.0.3)
[✓] Android Studio (version 3.2)
[!] Connected device

! Doctor found issues in 1 category.

The same thing happens when I try to start the emulator from the device dropdown pane. I can select Open Android Emulator: Nexus 5X API 28, and it will open the device but still show <No Devices> after the emulator has started.

Any help greatly appreciated!

Solution

Thanks to the comment from @Feu on the question above, I found out that the problem was the following:

I had to do some setup on the virtual device after unlocking it. I didn't notice this, but running flutter doctor -v made it all clear:

[!] Connected device
• Device emulator-5554 is not authorized.
  You might need to check your device for an authorization dialog.

Answered By - Thomas D. Frøysa