QWtPlot: Workaround for insertLegend bug?

[darkshu]

As I said there's no need more code - QwtPlot is create by Designer and in parent constructor ( after setupUI ) I call new legend, insertLegend
call updateLayout() in this place replot or similiar is without effect.
of course after display plot and resize it bad effect is gone - but it's not a solution, I have to show it fine in first view.
Some part of solution could be set

qwtPlot->setAutoReplot();

qwtPlot->setAutoReplot();

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but with such set QwtPlot get bigger ( about legend size ) and mess other view with grid layout which holds Widgets with plots.
setAutoReplot to true - false - don't work
Is there other ( better ) function to recalculate qwtPlot ??

Ok I found workaround by call updateLayout but just before display main widget