QStyleOptionProgressBar no longer rendering in QT 6.*

[Max S.]

I use QStyleOptionProgressBar in my Application to have a percent indicator in a Tree view. The code stopped working with QT 6.* . In QT 5.* the same code still works. Is this a bug or has something changed in the way delegate painting is handled?

The code is:

void InstrumentDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option,
                               const QModelIndex &index) const
{
  painter->save();

  // Setup basic layout
  QStyleOptionProgressBar progressBarOption = {};
  progressBarOption.state = QStyle::State_Enabled;
  progressBarOption.bottomToTop = false;
  progressBarOption.direction = QApplication::layoutDirection();
  progressBarOption.rect = option.rect.adjusted(0, 0, 0, 0);
  progressBarOption.minimum = 0;
  progressBarOption.maximum = 100;
  progressBarOption.textAlignment = Qt::AlignCenter;
  progressBarOption.textVisible = true;

  // Set the progress and text values of the style option.
  double percent = 50.0;
  progressBarOption.progress = (int)(percent);
  progressBarOption.text = QString::asprintf("%.2f%%", percent);

  //painter->fillRect(progressBarOption.rect, QColor::fromRgb(255,0,0));
  QApplication::style()->drawControl(QStyle::CE_ProgressBar, &progressBarOption, painter);

  painter->restore();
}

The result with QT6:

The result with QT5:

I created a small reproducer:
https://seafile.rlp.net/f/b1589ae16f7245d9b50d/?dl=1

My environment:
Fedora 39
QT 6.7.1 installed via the QT Maintenance tool.

[Pl45m4]

@Max-S said in QStyleOptionProgressBar no longer rendering in QT 6.*:

My environment:
Fedora 39

Wayland?
Could be a wayland issue then.
When using the Forum Search you will see that there are a lot window/rendering issues with Qt6 and wayland.

[Max S.]

@Pl45m4 I logged out and in again with xorg enabled.

But the rendering behaviour stays the same. So it seems to be an QT 6.* issue.

I validated that I use x11 via the terminal.

[max]~> loginctl 
SESSION  UID USER      SEAT  TTY  STATE  IDLE SINCE
     10 1001 max seat0 tty2 active no        

1 sessions listed.
[max]~> loginctl show-session 10 -p Type
Type=x11

[Christian Ehrlicher]

Please start with '-style fusion' and '-style windows' to see if it is a fusion or windows style problem. If so please provide a minimal compilable example in the bug.

[Max S.]

@Christian-Ehrlicher It seems a general rendering but. With the -style windows option the text is missing and the progress bar should be at 50%:

So it seems to be a general problem. I created the bug report https://bugreports.qt.io/browse/QTBUG-126426.

[Christian Ehrlicher]

You forgot to properly set the orientation in QStyleOptionProgressBar.state to QStyle::State_Horizontal.