[Qt-jambi-interest] Subclassing QLayout & QNoNativeResourcesException

[Frank Bergmann]

Hello, 

I had to implement a custom Layout but somehow things just don't work as
planned, directly after adding an item to the layout, like so: 

contentsWidget.layout().addWidget(legendItem);

and verifying by debugging addItem(QLayoutItemInterface item), that
everything is fine on my end (I even made sure that itemAt(index) within my
Layout class would return the right thing). However as soon as the addWidget
call completes, I'm in trouble: 

contentsWidget.layout().itemAt(0).widget()

returns with a com.trolltech.qt.QNoNativeResourcesException. (And that even
though my legendItem is still just fine.) The message that I get is: 

"Function call on incomplete object of type:
com.trolltech.qt.gui.QLayoutItem$ConcreteWrapper"

Which is not at all helpful. As final straw I turned to the documentation: 

http://qt.nokia.com/doc/qtjambi-4.5.2_01/index.html

which hints at implementations of a BorderLayout and FlowLayout example,
however

http://qt.nokia.com/doc/qtjambi-4.5.2_01/com/trolltech/qt/layouts-borderlayo
ut.html
http://qt.nokia.com/doc/qtjambi-4.5.2_01/com/trolltech/qt/layouts-flowlayout
.html

both are not very informative. I hope I can find some clues here, 

cheers
Frank