USB host permissions with Android 9 (Pie)

[otraupe]

I am trying to use an Arduino with a rooted Xiamo Pocophone F1 flashed with LineageOS 16. I am struggling how to get the user permission for USB host mode. I just don't know how to do it. Can someone help? Plugging the Arduino does not create an intent, so getting the permission on the fly does not seem to work. And I don't know the explicit "name" of the permission. So I don't know what to query. Thanks!

[xxxajk]

See here: https://github.com/xxxajk/PhysicaloidLibrary
Permissions are in the manifest.
The owner of this repository has not been around for years. It is obsolete.

[otraupe]

Thx for the reply!

All I can see is the "uses-feature" statement. But in modern apps you need to provide "uses-permission", as well. And you also need to actively query the needed permissions. This does not happen automatically any more. I only don't know its name.

I even saw evidence that this permission can be vendor-specific as e.g. in "com.sonyericsson.usbotg.SOMETHING".

[otraupe]

Actually, I don't see any permissions at all in the code. Am I looking at the wrong Manifest?

[xxxajk]

https://github.com/xxxajk/PhysicaloidLibrary/blob/master/SampleProjects/PhysicaloidTest/AndroidManifest.xml
See line 11.

[otraupe]

That is the "uses-feature" statement. How does this work as permission? With modern sdk versions at least it does not.

[xxxajk]

Works fine here, on marshmallow...

[otraupe]

Did you just run these examples or did you try to use the permission in your own code? I can't seem to create an app with this "permission" which actually asks me for permission. It seems I have to use a very old "target SDK", but I struggle with that.

[xxxajk]

Android will always ask for permission. That's normal.

[otraupe]

That exactly is the point: it does not. :)

[Lauszus]

This has been the case for some time. You need to request permission inside the application. Please refer to one of my apps:

https://github.com/Lauszus/FaceRecognitionApp/blob/f67687eba2c9b6d9cbad69322dc6a297e21327bb/app/src/main/java/com/lauszus/facerecognitionapp/FaceRecognitionAppActivity.java#L545-L547

https://github.com/Lauszus/FaceRecognitionApp/blob/f67687eba2c9b6d9cbad69322dc6a297e21327bb/app/src/main/java/com/lauszus/facerecognitionapp/FaceRecognitionAppActivity.java#L488-L500

For more information see: https://developer.android.com/training/permissions/requesting.

For more information requesting USB host permission on Android: https://developer.android.com/guide/topics/connectivity/usb/host#permission-d.

[otraupe]

Lauszus, thank you very much! I tried to follow the instructions on google developers closely:
https://developer.android.com/guide/topics/connectivity/usb/host#permission-d

I did not find them very straight forward and in particular did not understand that the permission string used there can be an arbitrary dummy string.

Now I finally found out, how it works. It seems there is no good tutorial out there. Maybe I write one.