STB Video Playback

[luckychap]

I tried to achieve this using QLabel and re-implementing the resizeEvent:

#include <QtGui>
 
class MaskedLabel : public QLabel
{
protected:
	void resizeEvent(QResizeEvent* event)
	{
		QLabel::resizeEvent(event);
 
		QPixmap pixmap(size());
		pixmap.fill(Qt::transparent);
		QPainter::setRedirected(this, &pixmap);
		QPaintEvent pe(rect());
		paintEvent(&pe);
		QPainter::restoreRedirected(this);
		setMask(pixmap.mask());
	}
};
 
int main(int argc, char* argv[])
{
	QApplication a(argc, argv);
	QLabel* label = new MaskedLabel();
	label->setText("Qt Centre!");
	QFont font = label->font();
	font.setPointSize(72);
	label->setFont(font);
	label->show();
	return a.exec();
}

#include <QtGui>

class MaskedLabel : public QLabel
{
protected:
	void resizeEvent(QResizeEvent* event)
	{
		QLabel::resizeEvent(event);
	
		QPixmap pixmap(size());
		pixmap.fill(Qt::transparent);
		QPainter::setRedirected(this, &pixmap);
		QPaintEvent pe(rect());
		paintEvent(&pe);
		QPainter::restoreRedirected(this);
		setMask(pixmap.mask());
	}
};

int main(int argc, char* argv[])
{
	QApplication a(argc, argv);
	QLabel* label = new MaskedLabel();
	label->setText("Qt Centre!");
	QFont font = label->font();
	font.setPointSize(72);
	label->setFont(font);
	label->show();
	return a.exec();
}

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We placed this MaskedLabel over the QWebView widget and tts showing us the video playing in the background but when I tried to resize the QLabel using setGeometry() method its not showing me video on full QLabel but to some parts.
NOTE: when I just moved the QLabel (not changing width and height) using setGeometry(), I can still see the video in background. The video vanished only when I try to resize it.

Why resizing remove the video and show transparent QLabel?