QWidget::render with DrawChildren flag

[Apocalypse]

Hi! I try to render widget's children into pixmap. Code:

//QWidget this;QPixmap  wpix
wpix=QPixmap(this->size());
wpix.fill(Qt::transparent);
this->render(&wpix,QPoint(0,0),QRect(0,0,640,1024), DrawChildren);

//QWidget this;QPixmap  wpix
wpix=QPixmap(this->size());
wpix.fill(Qt::transparent);
this->render(&wpix,QPoint(0,0),QRect(0,0,640,1024), DrawChildren);

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But in pixmap I get rendered widget's children and widget itself. Even with DrawWindowBackround flag. What could be wrong?