Brightness not changing on Android 9.0 Pie

[SankaCoffee]

I implemented your example for setting the brightness (on Android) but it doesn't change anything.
Also getting the brightness with Screen.brightness always returns 0, regardless of what i have defined in my settings.

[√] Flutter (Channel master, v0.10.1-pre.10, on Microsoft Windows [Version 10.0.17134.285], locale en-US)
[√] Android toolchain - develop for Android devices (Android SDK 28.0.2)
[√] Android Studio (version 3.2)
[√] VS Code (version 1.28.0)
[√] Connected device (1 available)

Running on Android 9.0 Pie.
Tested on emulator and physical device

UPDATE:
Also tested on another device with Android 7.0, there it does work

[Shakle]

It changes the brightness on my 9.0 Pie, but then I can't change it manually.

[d-wolf]

I can change my brightness on Pie.

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[✓] Connected device (3 available)
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