Scroll Area and Widgets repaint

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I have hundreds of widgets added in scroll area.
I get an update of widget displayed information in every 20 seconds.
Sometimes I add more widget too on run time.

Will it slow down the UI if I perform update of information on all widgets.
Though only 5 widgets are displayed on one page.

Should I perform update on all widgets or only on the displayed page.
UI is finger touch and scrolling has to be enabled on finger movement.

Any suggestions.

giesbert

Hi,

first of all, if you have hunders of widgets in a scroll view, why don't you use a model/view aproach? Table, List etc.

Second, if you do it all 20 seconds, I think it should not be a problem. If you only update the visible stuff, you have to take care of all others during scroll operations for refilling them :-(

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Thank you so much!
I think then I am good to go because I am doing model/view approach.
Where I have a separate singleton class which contains data containers and keep updating it.
Whenever there is change in data containers, it emits a signal to UI Class and it updates information for all widgets.

When I update all widgets, does it repaints all of them or the displayed page?

giesbert

[quote author="sVirgo" date="1318016313"]Thank you so much!
I think then I am good to go because I am doing model/view approach.
Where I have a separate singleton class which contains data containers and keep updating it.
Whenever there is change in data containers, it emits a signal to UI Class and it updates information for all widgets.
[/quote]

If you say you use the MV approach, why dou you have to update multiple widgets? If you cvhange data in a model, you just call emit dataChanged() and it updates the connected views.

[quote author="sVirgo" date="1318016313"]
When I update all widgets, does it repaints all of them or the displayed page?
[/quote]

AFAIK there is some logic behind repaint, which should clip out invisible widgets.

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Thank you for reply.

I am a newbie to QT. I need to check model/view approach again.

Is there any example which I can look to clip out invisible widgets in repaint, then I even don't need to change my code to model/view.

giesbert

it shopuld be clipped by the base system, so normaly, I would say: nothing to be done here.