Question

I’ve tried to create a custom widget plugin for QT Designer following this (http://doc.trolltech.com/4.3/designer-creating-custom-widgets.html) tutorial and was somewhat successful. Basically, I can place my new widget in Designer, but it doesn’t draw (I get an empty square instead of whatever I try to draw in my paintEvent method, I started with some custom code but reverted to copy pasting from the tutorial when that didn’t work).

While placing the custom widget my system log fills up with:

full_path/Designer: CGAffineTransformInvert: singular matrix.

Any suggestions?

I have built the example plugin that came with the qt sdk and there were no problems.

Answer 1

without the source it’s very hard to help you. Further I would prefer Qt 4.4 – it’s much more reliable and faster.

Here some common problems/hints:

• your DLL / .so file is not in /plugins/designer/
• you have a buggy paint() method
• your app or lib is missing some libs

Can you post your paint method?

ciao, Chris