error: cannot find symbol class MediaStyle after migrating to androidx

In AndroidX, that specific style is located in a different package. You need to prepend the media style with 'androidx.media.app'.

In other words:

builder.setStyle(new androidx.media.app.NotificationCompat.MediaStyle());

Curiously enough, I didn't need to implement this package in my gradle file, so it could be something related to AndroidX internal dependencies.

for my case, i need to add the following to my gradle file to find NotificationCompat.MediaStyle() class.

implementation "androidx.media:media:1.1.0"

https://developer.android.com/jetpack/androidx/releases/media

NotificationCompat.Builder(this, CHANNEL_ID)
.setStyle(new androidx.media.app.NotificationCompat.MediaStyle());

note that notificationCompat.Builder is in a different package (androidx.core.app.NotificationCompat) from MediaStyle.

Migrate android.support.v4.media.app.NotificationCompat to androidx.core.app.NotificationCompat

This looks like same answer @karan gave above. But the classes are different. Took me days to figure out that androidx.media.app.NotificationCompat was my problem.

The difference between the two; one is androidx.core..., the other is androidx.media...