[Interest] dynamic widget creation in QScrollArea

[Frank Rueter | OHUfx]

Hi all,

I am playing with the idea of writing a custom widget based on 
QScrollArea, where widgets are created as the user scrolls.
I'm just hoping to bounce the general idea of you guys here to see if 
I'm heading in the right direction:

I have a heap of custom widgets, potentially thousands, depending on the 
contents of a database.
I'd like to show them in a grid that fits as many widgets horizontally 
as will fit in the current window size (dynamic).
I would also like smooth vertical scrolling.

If I create a single parent widget with a grid layout that creates all 
widgets on start up, it takes ages.
So I'm thinking if I use the child widgets' visibleRegion() to find the 
ones currently visible in the scroll area, then figure out the indexes 
of the widgets in the rows above and below to create them dynamically, 
that should speed up the startup and still provide smooth scrolling.

Obviously I'd have to manually scale the scroll area based on the 
maximum amount of widgets and the parent widget's width to get an 
indicative scrollbar.
Not sure how tricky that will be.

Does that sound crazy or doable?

Basically I am trying to re-create the behavior of a QListView in icon 
mode. I tried using QListView with delegates, but couldn't get the 
delegates to provide the kind of complexity I need for the child widgets 
which I have already written (which are basically mini movie players 
that can be drag&dropped and have playback all at once on demand).

Any thoughts on this before I dive into this little experiment?

Cheers,
frank


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