Allow consolidate tracks display for directories in the "Computer" menu item

[eXWoLL]

Feature Description

When importing tracks from a hard drive or another directory with lots of subfolders, currently the library only displays the contents of individual folders when selected.

Having the option of a consolidated display of all the supported audio files from the directory one is exploring can simplify the process of going through multiple directories to only select a couple of tracks from each.

[ronso0]

Do you mean recursive file scanning, like see tracks from the selected dir and those from subdirectories?

[eXWoLL]

yup, i think?
Like, if you go to C/: Music/X, you see all the tracks in the library that are inside the directory; instead of what we have currently where you have to go into:

C/:Music/X/A
................../x/B...
and so on, including all the subdirectories included in each of these.

So if someone is lending me their external drive with their local library that has 34534535 directories and subdirectories, i do not have to go through each single EP on a 15 years discography to look up for tracks I might be interested in, and instead can select the level I would like for the library to show by entering the subdirectories if required.

Which would also help with selecting a lot of stuff from several subdirectories and adding them all into crates for example.

[ronso0]

Sure, all that makes sense.

The downside:
the Computer feature is really just a file browser showing only supported audio files.
The view is populated on click, like there is no caching per sidebar item.
You get an idea what that means if you want to jump back'n'forth between tracks and the USB root music dir, which contains thousands of tracks?

There are a few similar feature requests, and for me all issues related to Computer are resolved by #14687.
TL;DR if an item (dir) is part of your library Computer switches to the super fast db-based track view (like Tracks) and simply applies a dir filter. Requirement: temporarily add the USB to your library and issue a rescan.

[ronso0]

Duplicate of #11173, hence I'll close this.

If you have any more info/requirements for your use cases, please post them there.
If you want to try #14687 or cherry-pick commits to your working branch, let me know here.

FWIW the patch to enable recursive scanning in the current Computer view is minimal:
this

mixxx/src/library/browse/browsethread.cpp

Lines 130 to 132 in eeb11b8

	QDirIterator fileIt(thisPath.info().location(),
	nameFilters,
	QDir::Files | QDir::NoDotAndDotDot);

becomes (edit fixed)

    QDirIterator fileIt(thisPath.info().location(),
            nameFilters,
            QDir::Files | QDir::NoDotAndDotDot,
            QDirIterator::Subdirectories | QDirIterator::FollowSymlinks);