QPainter

[phil_]

Hello,

I want to use QPainter to draw very simple lines and points. I checked the docs and wanted to copy the example, but the following code doesn't work:

int main(int argc, char *argv[])
{
	QApplication app(argc, argv);
	QWidget fenster1;
	fenster1.resize(400,400);
 
 
	QPainter achsen(&fenster1);
 
	achsen.setPen(QPen(Qt::blue,2));
 
	achsen.drawPoint(200,100);
 
	achsen.drawLine(100,100,301,301);
 
	fenster1.show();
 
    return app.exec();
}

int main(int argc, char *argv[])
{
	QApplication app(argc, argv);
	QWidget fenster1;
	fenster1.resize(400,400);


	QPainter achsen(&fenster1);

	achsen.setPen(QPen(Qt::blue,2));

	achsen.drawPoint(200,100);

	achsen.drawLine(100,100,301,301);

	fenster1.show();
    
    return app.exec();
}

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It doesn't return an error, but I can neither see the line nor the point. It just displays an empty window. Where is the mistake?

Thanks.