App not listed in “Apps with usage access” activity

问题

I'm writing an android app for marshmallow (sdk 23) with Android Studio, which creates some charts/diagrams by retrieving the past network activities with the NetworkStatsManager-class.

Therefore I added the necessary permission in the manifest:

<uses-permission
    android:name="android.permission.PACKAGE_USAGE_STATS"
    tools:ignore="ProtectedPermissions" />

The "Apps with usage access" is opened automatically with an intent, so the user can permit the needed access.

The problem is: My app is not listed in the "Apps with usage access" anymore? The strange thing is, that it worked fine until some days ago (?).

I did already a "project clean", but no luck..

来源：https://stackoverflow.com/questions/39067283/app-not-listed-in-apps-with-usage-access-activity