flickering problem

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ultrasparc

Beginner

Posts: 12

Wednesday, February 27th 2008, 2:35pm

flickering problem

When I resize my application there is some flickering on the widgets that use background.
I use a png background image that is repeated many times. The background is set by css.
How can i fix this problem?

nijish

Trainee

Posts: 154

Location: Bangalore

Occupation: Software Engineer

Wednesday, February 27th 2008, 2:41pm

the widget flickers or is it the whole win?
css??...

ultrasparc

Beginner

Posts: 12

Wednesday, February 27th 2008, 3:05pm

Flickers the widget that has background.
css = cascading style sheets
http://doc.trolltech.com/4.3/stylesheet.html

are there other ways to set a widget background?

nijish

Trainee

Posts: 154

Location: Bangalore

Occupation: Software Engineer

Thursday, February 28th 2008, 8:16pm

qss huh? it could have been konq too..

1. what if you change png to some other format say jpeg/bmp/gif?
2. is the image with alphachannel? semi-transparent?
3. have you tried 0-margin 0-border 0-padding?

ultrasparc

Beginner

Posts: 12

Monday, March 3rd 2008, 10:05am

I tried all these things, the problem persists.

macabre13

Trainee

Posts: 127

Location: Poland/ Wroclaw

Occupation: sw developer

Monday, March 3rd 2008, 1:20pm

To avoid flickering you should try double-buffering.

- ebm - noise - industrial -
I always could be wrong.
Lets share knowledge!

ultrasparc

Beginner

Posts: 12

Wednesday, March 5th 2008, 9:57am

How can i do?
Qt 4 does not use double buffer by default?

nijish

Trainee

Posts: 154

Location: Bangalore

Occupation: Software Engineer

Thursday, March 6th 2008, 7:01pm

mac: flickering happens when rendering is done twice on same framebuffer memory area rite? so i think he will need to 'remove' double buffering. wat say?

nijish

Trainee

Posts: 154

Location: Bangalore

Occupation: Software Engineer

Thursday, March 6th 2008, 7:04pm

ultra: found a solution?
i think programatically it would be too complex. for starters, why not try a show() and hide()? ie, hide the widget/appln and then do rendering and the do show().
wat would happen then?