[Qt-interest] Interview and fetchMore()

[Arnold Krille]

Hi,

On Monday 08 June 2009 13:41:02 Philip Scott wrote:
> >> Is it possible to use it to add rows for a particular
> >> granularity as you 'zoom in' (so it would need to be parametrized
> >> somehow for the scale you are currently viewing at; perhaps a start/end
> >> datetime and a number of samples required).
> > You could create a zooming-proxymodel between the real data model and the
> > views. Then you only need another gui to control the proxy (to be
> > independant)
> > or subclass the KDChart to have the zooming functions inside.
> I was having similar thoughts, although I couldn't quite pin down
> concretely in my mind how this might be achieved.
> Do you mean creating a
> proxy model in which zooming in added extra points to the end of the
> dataset?

No, that would not be good. Because I think most views display the data 
unsorted, ie. in the sorting the model provides. That would give you strange 
graphs. Unless you add a sort-proxy-model too.

What I mean: On zooming in you would need to add rows in the middle. And if it 
really is zooming in, the boundaries would move to, so rows from top and 
bottom would be removed.
Which could be optimized into zooming by factors of 2 where the number of rows 
doesn't change but the data in the rows and in the according header.

Have fun,

Arnold

PS: No need to CC me, I am subscribed.
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