Due to different loginResponse objects being picked up for getting the playlist and the art, the playlist is working while the art is not. Log example:

192.168.1.6 - - [02/Sep/2021:07:15:22 -0300] "GET /ampache/server/json.server.php?action=playlist_songs&auth=b2b7a8585dcdd75b7278fcaee02296f6&filter=9&offset=0&limit=2147483647 HTTP/1.1" 200 319163 "-" "okhttp/3.14.9"
192.168.1.6 - - [02/Sep/2021:07:15:23 -0300] "GET /ampache/image.php?object_id=2142&object_type=album&auth=b2b7a8585dcdd75b7278fcaee02296f6&name=art.jpg HTTP/1.1" 200 94566 "-" "okhttp/3.14.9"
192.168.1.6 - - [02/Sep/2021:07:15:26 -0300] "GET /ampache/server/json.server.php?action=get_art&auth=caa17cbc32bbc40a258311ec75183818&type=artist&id=222 HTTP/1.1" 200 84 "-" "okhttp/3.14.9"

The invalid ID is that for the art, which causes the background to be blank. We seriously need some way to update login response if they are found to be outdated...

My intention with that screen is showing the latest artists or the latest albums played or something, with their corresponding artwork. This may require quite a bit of work, and several subtasks...

If a song is disabled in the server, via the web interface, it gives a 404 error to the player and it doesn't continue playing any other song, even if the problem song is skipped.

It seems that if I go see the artists, return to the albums and try to search, it will search for artists instead of albums. Strange...

I think I already send the correct image to the mini player - it must be the album artwork - however, I still see the gray image of the musical notes, there must be something wrong there.

When I replaced the default progress bar with that of the ExoPlayer, I lost the colorings of that original bar. I could recover the colors and use them here so it doesn't look all white and boring...

Unexpectedly, I found that a mapping method over a LiveData object can be triggered by way of a Transformations:

Transformations.switchMap(dataSourceFactory.getNetworkStatus(),
NetAlbumsPageKeyedDataSource::getNetworkState);

The switchMap allows to invoke the method in the second parameter for a change in the observed object (in the first parameter). This can be used to trigger searches on the search string, to replace the current method where a new datasource is created for each change in the search string.

There is no button for shuffling the playlist. Also, there is no infrastructure behind-the-scenes to do it, this would require some amount of work to get done.

I don't know why, but the status of the Play button is not restored correctly when the application is restored. I thought I fixed this?

The string used to query for albums stays within the AlbumsRepository and there's no way to reset the search. Maybe after selecting songs to play I should reset it? Or if I just select an album, I create a new Repository with an empty search string to force it to reload the whole list of albums?

As the playlist is stored in a ViewModel, it ends up being empty when the application is restarted. The current playlist must be stored in the ViewModel and picked up by the method to restore the state.

I think that the response from the server is actually 200 OK, but due to a permissions error, there is a warning inserted into the PHP output and it gets sent along with the Json response. I wonder if there is a way around this? I don't think so... I'll think about it, though.

Other players have an Add to Playlist button. The current button replaces the songs in the list with the selected ones. Maybe I'll add another, add to playlist button?

Issue discovered after the first field test: the mini-player view (at the top of the sliding window) shows the data of the first item on the list. Whe hitting play, as the screen receives the MediaItem being played from the MediaPlayerService, the correct item is shown.

Capture screenshots of the player to add them to the github project page and make it more attractive...

Other music players have equalizers. I must have a demo equalizer interface somewhere, I would have to add it here. In fact, the 3-bar button right below the artwork in the palyer was meant to show the equalizer but it's not showing now.

This is due to the message sent by the progress bar when it is changed not being captured by the MainActivity to send to the MediaPlayerService.

Create a splash screen, with the new logo!

Currently the Paging version used is 2. It is possible to update to version 3.

There is no button for repeat. All music players have it. This should be fairly easy to do. The current buttons for the timer and volume, taken from the original implementation of the player, are still there but they could be replaced with those of shuffle and repeat. Also, apart from the button, some code behind-the-scenes would be required, this should be fairly easy as well, because Exoplayer contemplates the use of Repeat.

In other applications, clicking the notification doesn't open the notification. This was working at some point, when the notification manager created a PendingIntent, but that was changed and now no longer works as expected.

Some day... some day, when this player is finished, or close to finishing, I'll add it to Google Play so it's easy to download by other enthusiasts of Ampache.

Strangely, a song that has not been selected in the Choose songs screen, and is not sent to the MediaPlayerService, is shown in the Playlist view. Later, the playlist view is confused and highlights the track by its track order, which would be fine as long as the Exoplayer playlist matches the contents of the view. Why unselected songs are sent to the playlist view?!?

When the session expires and the user is browsing the list of albums/artists/playlists, the Server sends a response which contains a null data object and an error object, but the callback, which requires the parameters to be non-null, causes an assertion fail and the application crashes. The application should check if the data object received from the server in the Response is non-null, and in case it is, it should be able to catch the error and trigger a renewal of the session key.

After the first "field test" of the player, some issues were detected, among these, that the RecyclerView selection is cleared when the screen is rotated. There must be a way to keep the state when the screen is rotated...

The state of the buttons for Play is not kept when the screen is resumed. This may be due to the application state not being kept.

My intention is to show the face of the artist or something. The current message from the MediaPlayerService contains the album artwork URL but not that of the artist. It is possible, however, to send it with an "Extras" bundle. Something to think about...