Fix crash when long-pressing stream while player is starting

[Stypox]

What is it?

• Bugfix (user facing)
• Feature (user facing)
• Codebase improvement (dev facing)
• Meta improvement to the project (dev facing)

Description of the changes in your PR

This PR fixes a NullPointerException in PlayerHolder.getQueueSize() that could happen when the player's queue is null, i.e. when the player is starting. It also adds @Nullable here and there so that Android Studio's linter reports risks of NPEs.
I think this PR should be merged before the next release as it's just adding an if (... != null) but solves a big issue.

Fixes the following issue(s)

• Fixes Crash on tap and hold in search results while bg queue is loading #7608
• Fixes Video loading / buffering Crash. #7528
• Fixes Enqueueing videos quickly crashes the app in version 0.21.13 #7305
• And many other duplicates

APK testing

The APK can be found by going to the "Checks" tab below the title. On the left pane, click on "CI", scroll down to "artifacts" and click "app" to download the zip file which contains the debug APK of this PR.

Due diligence

• I read the contribution guidelines.

[Feuerswut]

Seems to work. Its now extremely fast, so I dont know weather I reproduced the issue exactly but no crashes yet.

[litetex]

Code LGTM

[goyalyashpal]

just for records, this does fix not #7608 , i have given my input over that issue itself

[Stypox]

@yashpalgoyal1304 I fixed your problem in the last commit, please check again the APK ;-)
Now the "Enqueue" button will just not show up if the playQueue is null, i.e. not available

[sonarqubecloud]

SonarCloud Quality Gate failed.   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

0.0% Coverage
16.0% Duplication

[Stypox]

Ignore the failure by sonarcloud, I just had to edit many duplicated lines, which will be solved by #7570

[litetex]

Code LGTM 😄

However I didn't test it so far...

[goyalyashpal]

I tested it,

and imo, showing the Enqueue option but graying it out (with properly chosen colors) will be more indicative and more fool proof.

what do others think??

[litetex]

@yashpalgoyal1304
Thank you for the feedback

In my opinion not showing the option is enough:

• When it's grayed out/disabled a user may wait until it gets enabled which wouldn't happen. If we implement "the enabling" it would likely require a new PR because the current code was not designed for such things
• It doesn't happen so often
• A user can simply retry long-pressing
• For now it fixes the crashes - We/You can open an additional feature request after it was fixed 😄

[goyalyashpal]

fair 👍 (:

[eternal-sorrow]

So this PR does not fix the problem, just masks it by hiding the "Enqueue" menu option while loading? And if I want to quickly enqueue several videos, I have to wait while it loads?

[litetex]

So this PR does not fix the problem

It fixes the crash by not allowing to enqueue anything while the player is not ready for it.

And if I want to quickly enqueue several videos, I have to wait while it loads?

I assume so. But it shouldn't happen so often in the first place.
Usually people play whole playlists or actually watch the video.

See also → We/You can open an additional feature request after it was fixed 😄(from #7704 (comment))