Size / Resize on qwtplot

Hi,

i have on a QDialog (Layout Grid) a horizontal layout with a qwtplot widget inside - if i open this window - the size of the widget fits to the horizontal layout size perfect. If i change the count of samples (at runtime - the dialog is still open) the size of the qwtplot widget shrink to 50% of the orignal size - if i try to resize the dialog window - the size of the qwtplot widget expand immediately to the size before.... .

What is the reason for the downsize of the widget and can i avoid this down resize of the widget?

Thanks Tom

Obviously something has an effect on the size hint of the plot, but without having a running example demonstrating the issue it is hard to say what it is in detail.

Uwe