> > 29.01.2014, 14:43, "Igor Mironchik" <igor.mironc...@gmail.com>: >> Hi. >> >> I'm implementing AbstractScrollArea and ScrollArea for QtMWidgets library. >> >> Almost all have been done except painting scroll indicators. >> >> The problem is that that I can't draw on child widget. I installed event >> filter for the child widget, and in the filter I invoke paint method for >> scroll indicators. All is ok, but child's paint event become after event >> filter's paint event. And child's paint event paints on my scroll >> indicators. >> >> Is there any way to invoke child's pain event in filter method? I can't >> simple invoke child's paint event because this method is protected... >> >> Any adeas?! >> > You cannot neither paint on child widget, nor manipulate paintEvents' order. > > There are 2 possibile ways: > > 1. Implement these widgets as one custom widget (best performance, more code). > For example, your scroll area can take rendering delegate with paint() method, > called in proper moment from your paintEvent() to draw contents.
It's possible. But I will impose a restriction for users of ScrollArea. They will be required to subclass from specific widget to put something for scrolling. Where I want to do API of ScrollArea as QScrollArea. I.e. to do possible to put any widget to the ScrollArea without thinking of painting scroll indicators and so on. > 2. Add 3rd widget on top of scroll area (worse performance, but simpler) The first approach is simpler to implement for me than second. But I don't know what will be better for the end-user. In the second approach the user will not have any pain with subclassing. He will simple put widget to the ScrollArea and that's all... What better to implement? -- Best Regards, Igor Mironchik. _______________________________________________ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
