how to draw a line over a frame?

[athulms]

in my progrm i am using 4frames(UI). I use show/hide frames using buttons. I have two draw a line in the 3rd frame. I have used the code

void MainWindow::paintEvent(QPaintEvent *e)
{
QPainter painter(this);
QPen linepen(Qt::red);
linepen.setWidth(25);
linepen.setCapStyle(Qt::RoundCap);
painter.setRenderHint(QPainter::Antialiasing,true);
painter.setPen(linepen);
painter.drawLine(point,point2);
}

void MainWindow::paintEvent(QPaintEvent *e)
{
QPainter painter(this);
QPen linepen(Qt::red);
linepen.setWidth(25);
linepen.setCapStyle(Qt::RoundCap);
painter.setRenderHint(QPainter::Antialiasing,true);
painter.setPen(linepen);
painter.drawLine(point,point2);
}

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since i have used the painter(this) the drawing is done on the main window so i cannot see the line on the frame. since frames(with background images) are placed over the main window.


Now i try to use painter(ui->frame3)

But it doesn't work. pls help me, thanks in advance

[stampede]

Asked here already. What part of the sample code you don't understand ?

[ChrisW67]

The (default) painting of the child will happen after the painting of the parent. If you override the paint event of the parent then why do you expect that the painting behaviour of a child widget will be changed? You want to override the paint event of the child widget.