Qframe lines and QTextEdit scrollbar are not drawn correctly

[titan99_]

Hello Community

As you can see in the pictures, not all frame lines of a QTableView are drawn correctly and the scrollbar of a QTextEdit is also not drawn correctly.

Class with the QTableWidget:

class DateTable : public QWidget
{
	Q_OBJECT

public:
	explicit DateTable(QWidget* parent = nullptr) :
		QWidget(parent)
	{
		tool_bar = new QToolBar(tr("tool_bar"), this);
		tool_bar->addAction(tr("Add Row"));
		tool_bar->addAction(tr("Delete Row"));

		table_view = new QTableView(this);

		QVBoxLayout* vbox_layout = new QVBoxLayout(this);

		vbox_layout->addWidget(tool_bar);
		vbox_layout->addWidget(table_view);

		setLayout(vbox_layout);
		layout()->update();
	}

private:
	QToolBar* tool_bar;
	QTableView* table_view;
};

Does anyone know what I can do to ensure that the lines are drawn correctly or what I am doing wrong so that the lines are not drawn correctly?

[gde23]

Do you have a stylesheet set for the application or the widgets that get drawn incorrectly?

[titan99_]

@gde23
Thanks for the answer.

No, I don't have set a style sheet yet. I briefly looked at the following pages from the Qt documentation:
Qt Style Sheets Reference
Qt Style Sheets Examples
QWidget styleSheet : QString
QApplication styleSheet : QString

I I'll try this later as I don't have a lot of time right now.

Do I have to define a stylesheet so that the widgets are drawn correctly?

[Bonnie]

@titan99_ said in Qframe lines and QTextEdit scrollbar are not drawn correctly:

Do I have to define a stylesheet so that the widgets are drawn correctly?

No, he just means stylesheet may cause that kind of incorrect drawing.
I tried your code and the frame is drawn without problem, so this part doesn't seem to be the reason.

[titan99_]

@Bonnie said in Qframe lines and QTextEdit scrollbar are not drawn correctly:

I tried your code and the frame is drawn without problem, so this part doesn't seem to be the reason.

Thank you very much for your effort.

I changed the screen scaling settings from 125% to 100% and the widgets were drawn correctly.

In the documentation I found these pages about high DPI:
enum class Qt::HighDpiScaleFactorRoundingPolicy
High DPI, this side says:

Qt will automatically account for the display resolution when using higher level APIs such as Qt Widgets and Qt Quick, and applications only need to provide high-resolution assets, such as images and icons.

I searched for high dpi using the forum's search function.

The return value from main_window.devicePixelRatio(); was 1.25, which corresponds to my system setting. But with the scaling 1.25 the problem remains.

Edit:

QApplication::setHighDpiScaleFactorRoundingPolicy(Qt::HighDpiScaleFactorRoundingPolicy::Round);
QApplication app(argc, argv);

If the static member function setHighDpiScaleFactorRoundingPolicy before QApplication app (argc, argv); is called, everything was drawn as expected. highDpiScaleFactorRoundingPolicy() previously returned 5, which corresponds to Qt :: HighDpiScaleFactorRoundingPolicy::PassThrough.