Support viewing (launching) current item

[tsujan]

By double-clicking it or through its context menu item if it's a file.

Also, remember the last dir on opening files in eaach session.

Also, set Qt::AA_UseHighDpiPixmaps.

Also, commented out QDebug messages to be able to see temporary ones ;)

[agaida]

Works fine for me - but an additional entry "Open with ..." would be nice too. Example: *.svg - one might want to use inkscape or a simple text editor

[tsujan]

@agaida What you want is quite valid. Currently, it uses the default app that's assigned to the mime-type. However, when item DND is implemented, the item could be dropped anywhere without further extraction because it's already extracted (in /tmp and temporarily).

That being said, I'll think about "Open with ..." later -- not for this PR.

[tsujan]

Oh, with the kind of DND I have in mind, the item can be dropped into text editor too -- it's not like engrampa but like Arqiver.

[agaida]

I'm fine with - but we should not forget

[tsujan]

but we should not forget

I won't but, for now, there are more important features to implement and bugs to fix. For example, when the header of a 7z archive is encrypted, lxqt-archiver can't open it although it's equipped with the required tools (that may be easy to fix); encrypted files don't have any emblem to show that they're password protected; 7z archives containing files with different passwords aren't well supported; etc.

I think, with the clean code @PCMan has written, no problem should be hard to fix -- I just hope I won't make his code untidy.