Added music player service in background; 'open' button in details used to test (temporal)
Added MediaController user interface to handle audio files in the MediaService
Basic video preview in a separate actitivy
Error messages for video playback reviewed
Removed unused code in MediaService
Fixed bad behaviours when an error occurrs during audio playback
Error messages for media playback improved
Do not try to play files in streaming by now
Created preview fragment to show previews for audio, video and images; shown when a downloaded file in these categories is downloaded
Now it can be build :\ ...
Added basic menu options to the preview fragment: open, delete, see details
Added progress bar for file transfers in details view (untested)
Fixed ClassCastingException
Progress bar in details view is successfully updated
Visibility fixes in progress bar
Fix: clicking on an upload notification goes to file details, never to file preview
FIX: IMPORTANT, to keep the life cicle of fragments, super() must be called in @onSaveInstaceState, at the holder Activity
Fixed ClassCastException in FileUploader
Fixed update of progress bar for file transfers in landscape mode
Automatic download of previewable files in portrait mode