GUI fixes: Elide playback name label if needed and…

[tsujan]

If the name is too long, elide it centrally, so that a horizontal scrollbar isn't needed (and isn't shown).

Also, don't force a height on progressbars because some widget styles may not show any bar with a forced height.

Closes #99 and closes #75

[tsujan]

Before:

After:

[yan12125]

The class ElidedLabel seems the same as the one from libfm-qt [1]? I wonder if both classes can be merged into one.

[1] https://github.com/lxqt/libfm-qt/blob/master/src/fileoperationdialog_p.h

[tsujan]

The class ElidedLabel seems the same as the one from libfm-qt?

Yes. I'd made it for libfm-qt's file operation dialog and for a similar reason. Here, I just copy-pasted it.

I wonder if both classes can be merged into one.

pavucontrol-qt and libfm-qt have no common LXQt dependency (except for lxqt-build-tools). IMHO, adding a dependency just for a simple code like this would be too much.

I think, at some point, Qt itself should add this property to QLabel (but, apparently, there's no plan for it). It reminds me of QLineEdit's clear button, which was added to Qt5, at last.

[yan12125]

Copying this small class for two times is fine, but I guess such a class will appear in more LXQt projects, and merging will be better then.

For now I'm fine with the current approach. Feel free to merge if you wish.

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I think, at some point, Qt itself should add this property to QLabel (but, apparently, there's no plan for it)

Looking into Qt's bug tracker, and I feel this comment implies that will be a complex feature

if the label was set to use rich text (html: clickable URLs, coloring, etc.), the rich text support shouldn't suddenly disappear when eliding kicks in, it should remain rich text support while eliding.

(https://bugreports.qt.io/browse/QTBUG-1277#comment-221318)

[tsujan]

Looking into Qt's bug tracker, and I feel this comment implies that will be a complex feature

Yes, because of the rich text, which is the whole point. With a plain text, a simple subclassing (like the above) does the job.

For now I'm fine with the current approach. Feel free to merge if you wish.

Thanks!