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

[Heiko Steindl]

Hello !

Thanks all for your fast answers!

Currently I tried it with blockSignals and it is much faster :)

But I'll create a custom model for this.

Is it ok, to emit the dataChanged() signal just one time after all  
data is changed or should it be emitted more times (e.g all 1000  
changes)?

Thanks a lot for your help!
--


Mit freundlichen Grüßen

Heiko Steindl

Computerhaus EDV-Handels Ges.m.b.H
Wienerstrasse 35a
8605 Kapfenberg AUSTRIA

Tel: +43 (0)3862 27777
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E-Mail: heiko at kom.at

Am 13.06.2009 um 11:51 schrieb Arnold Krille:

> On Saturday 13 June 2009 11:08:58 Sean Harmer wrote:
>> On Saturday 13 Jun 2009 09:47:21 Arnold Krille wrote:
>>> On Saturday 13 June 2009 01:09:04 RZ wrote:
>>>> But the block signals effect was quite overwhelming and  
>>>> sufficient - so
>>>> I stopped optimizing everything else ;-)
>>> As far as I know this means all the update signals are then send
>>> afterwards. Which mean after changing 10.000 data points, instead  
>>> of a
>>> continuous stream of 10.000 dataChanged(index) signals, you will  
>>> get them
>>> all after the signals are unblocked again.
>> I don't think that this is true. Blocked signals just never get  
>> emitted
>> (except for the destroyed() signal).
>
> Then its even _really_ bad to block signals upon changing data,  
> because then
> the gui doesn't get a single signal that the values changed...
>
> Arnold
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