Add option to continue sidebar previews when mouse released

[Spekular]

Adds a new option to the (incredibly crowded) General>UI section of our preferences that allows clicked samples in the sidebar to play to completion/interruption. With this setting enabled, sample previews will not stop on mouse release, but will still stop when:

• Another sidebar item gains focus (another preview starts, cursor moves to folder)
• The sidebar loses focus (another area is clicked on)
• The sample finishes playing

Thanks to changes in #5764 (stopping previews on focus loss, specifically), this should no longer cause the crash described in #5736. Please test this! Somewhat related: #5427

Milestoning for 1.3 since 1.2 had this option... ish.

[LmmsBot]

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Linux

• Linux (AppImage): lmms-1.3.0-alpha.1.14%2Bg6597161-linux-x86_64.AppImage (build link)

Windows

• Windows 32-bit: lmms-1.3.0-alpha.1.14%2Bg65971610d-mingw-win32.exe (build link)
• Windows 64-bit: lmms-1.3.0-alpha.1.14%2Bg65971610d-mingw-win64.exe (build link)
• Windows 32-bit: lmms-1.3.0-alpha-msvc2017-win32.exe (build link)
• Windows 64-bit: lmms-1.3.0-alpha-msvc2017-win64.exe (build link)

macOS

• macOS : lmms-1.3.0-alpha.1.14%2Bg65971610d-mac10.13.dmg (build link)

🤖

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[superpaik]

It works perfectly as described. Only one minor thing. When you said (regarding scenarios to stop sample from playing): "Another sidebar item gains focus (another preview starts, cursor moves to folder)", does it means that if I click (or open/close) on a folder (not a sample) the current sample should stop? It doesn't. Personally I think that's a better behaviour than stop it, but I don't know if this is intended or a side-effect.
No crashes found (related to #5736 )
It saves and loads the configuration setting.

[Spekular]

When you said (regarding scenarios to stop sample from playing): "Another sidebar item gains focus (another preview starts, cursor moves to folder)", does it means that if I click (or open/close) on a folder (not a sample) the current sample should stop? It doesn't.

I was thinking about the arrow keys when I said that, so I forgot about the mouse. Thanks for pointing it out!

Personally I think that's a better behaviour than stop it, but I don't know if this is intended or a side-effect.

It wasn't intended, but I'm not sure if I should change it or not. I'll test a bit in LMMS and other DAWs and see what feels natural.

Also something I realized yesterday and was planning to fix as soon as I got the time: preset previews will likely play forever with this setting on, so I need to restore the previously existing logic that ensured they always turn off on mouse-up.

[Spekular]

Latest commit restores proper behavior for preset previews, so they stop when the mouse is released as they should. Nothing else should be different.

Both Ableton and FL let previews continue when folders are opened/closed, and it doesn't feel bad or unintuitive to me, so I'm leaving that as is.

[Veratil]

Nothing stands out to me, it looks good. I haven't built and tested, but the logic is sound.

[IanCaio]

Will later try to download the build and test, but as far as the code goes LGTM!

[Spekular]

Quoting myself and IanCaio from Discord:

do you still intend to test #5787 or should I go ahead and merge it?

[..] I didn’t test it yet but I did review the code and it all looked good, since others have tested and had no issues it’s alright by me if you want to merge it now