Issue Type

[ ] Question
[x] Bug
[ ] Improvement
[ ] Build system related
[ ] Performance
[ ] Documentation

Description and/or steps/code to reproduce the problem

I'm using Osmdroid in PhoneTrack-Android and everything works fine for Android <= 9.

I can't figure out a way to load Mapsforge .map file in Osmdroid on Android 10. I guess it's caused by the new way of managing storages in Android 10. I saw that things were fixed for tile caching (#1512 #1571).

For the "classic" online tiles providers, it seems the tiles cache is indeed written and red correctly.

So my problem is, first, that the old code sample (findMapFiles method) does not seem to explore the storages according to new Android storage management and fails to find .map files in the default place (/default-storage/osmdroid/*.map). It's looking in /storage/emulated/0/osmdroid/ and /mnt/media_rw/1501-3B0F/osmdroid/ on my virtual device and none of that exists or is accessible.

My second problem is that I can't find a way to "manually" add a .map file (as a workaround). Even if I create a file descriptor to a .map file using the absolute file path I can get from the adb shell, Osmdroid crashes when I try to display it :

org.mapsforge.map.reader.header.MapFileException: cannot read file: /storage/1501-3B0F/osmdroid/languedoc-roussillon.map
        at org.mapsforge.map.reader.MapFile.<init>(MapFile.java:247)
        at org.osmdroid.mapsforge.MapsForgeTileSource.<init>(MapsForgeTileSource.java:69)
        at org.osmdroid.mapsforge.MapsForgeTileSource.createFromFiles(MapsForgeTileSource.java:170)
        at net.eneiluj.nextcloud.phonetrack.android.activity.MapActivity.getMapsForgeTileProvider(MapActivity.java:391)
        at net.eneiluj.nextcloud.phonetrack.android.activity.MapActivity.setTileSource(MapActivity.java:1047)
        at net.eneiluj.nextcloud.phonetrack.android.activity.MapActivity.access$2300(MapActivity.java:110)
        at net.eneiluj.nextcloud.phonetrack.android.activity.MapActivity$13$1.onClick(MapActivity.java:1030)

while the file descriptor says the file exists.

I'm currently loosing time and energy trying to convert files Uri (obtained with ACTION_GET_CONTENT intents) to a File I could provide to Osmdroid. Probably a dead end 😁.

I'll be glad to provide more information if necessary.

Environment

Virtual Android device (API 29) without google services installed.

If it's a bug, version(s) of android this affects:

Android 10 (API level 29)

Version of osmdroid the issue relates to:

v6.1.6