uamp | A sample audio app for Android | Android library

I have a pivot table as shown below.I need to find the maximum and minimum value present in the column "Chip_Current[uAmp]".could you please tell me how to approach this?

Please see my code below

I developed a media app with reference to UAMP, but I encountered the following problems. The media switch output screen opened from the notification cannot display the media information being played. But there is UAMP, not sure what I missed? Does anyone know the reason? Thank you

As the result of kmean clustering I assigned persons to different clusters over several years. See the code for a small example.

I am using the UAMP-Example provided by Android on GitHub.

The Uamp-Project has been optimized by myself and now i would like to change the com.example.android.uamp (and all corresponding files for Android Auto too) to my custom ch.test.appname.

I tried to change soo many files but got dozens of 'file not found' Errors.

Which files to i have to change?

I'm new to android development. I want to create a music player that functions in a client-server fashion. I'm trying to create the server part for now. I found out that I could achieve this using MediaBrowserServiceCompat as it says in the official documentation here. But when I tried to use it in my project it says Unresolved reference: MediaBrowserServiceCompat Although I've set Android Studio to import needed libraries automatically, I tried importing android.support.v4.*, android.support.*, androidx.* explicitly, hoping it might work but it didn't as it turns out. So I went over to the GitHub repo of UAMP(Universal Android Music Player) for some help. I found the statement import androidx.media.MediaBrowserServiceCompat in this file. But I couldn't find any library named so

And why my Manifest says MediaPlaybackService must extend android.app.service?

How am I supposed to use it? Thanks!

Edit: I did a little bit of research and tinkering. I tried changing the service name in my Manifest and the associated class name as well to MyMediaBrowserServiceCompat and magically it worked(sort of). So now, my question is, is it normal behavior? Should changing the service name really affect this situation? And if its so, how on Earth it works with different names(something not similar to the class name itself) on other peoples' machines? And secondly, now my code says There's a cycle in the inheritance hierarchy for this type I searched the web and found this. So I know what that message means but I can't figure out how to solve it in this case. And my Manifest still says the same: MyMediaBrowserServiceCompat must extend android.app.service

In my mind, Kotlin is null safe.

The Code A is from the project Universal Android Music Player Sample, you can see here

It seems that val rootMediaId: LiveData is not null safe in Code A, a null string can be assigned to rootMediaId, I don't know why Android Studio can compile these code, could you tell me?

I think that the Code B is reputable code.

Code A