[Qt-interest] Model/View speed of Models with many many items and item changes

[RZ]

>  
>> improved speed about a factor of 100. I don't know why - but it worked ;-)
> 
> Well of course, because anything thats waiting for the various singals
> that are being sent out won't get any while your changing the data. In
> particular some views relayout their content on certain signals, so if
> you update 10000 items in 10000 steps each time sending the signals, the
> view might relayout each time. 

Well, for sure. Maybe my statement was a little bit incomplete. The app 
had to load a lot of data and simply was "too slow". I tried several 
thinks like e.g. optimizing the C++ code or

myView->setUpdatesEnabled();

But the block signals effect was quite overwhelming and sufficient - so 
I stopped optimizing everything else ;-)