为什么要获取QWindowsWindow::setGeometry:无法使用Qt5.12.0设置几何警告

我将一些代码从Qt 5.6.0迁移到了5.12.0。令人惊讶的是,我收到了很多关于 QWindowsWindow::setGeometry

我可以在MCVE中隔离这个问题,它非常简单和最小,所有的父母看起来都很好,但是,当按下按钮时,我们会得到警告:

QWindowsWindow::setGeometry: Unable to set geometry 132x30+682+303 on QWidgetWindow/'QDialogClassWindow'. Resulting geometry:  132x42+682+303 (frame: 4, 28, 4, 4, custom margin: 0, 0, 0, 0, minimum size: 116x42, maximum size: 16777215x16777215).

main.cpp:

#include <QApplication>
#include "mainframe.h"
#include <qDebug>

void MessageOutput( QtMsgType type, const QMessageLogContext &context, const QString &msg)
{
    qDebug() << msg;
}

int main( int argc, char* argv[] )
{
    QApplication app(argc, argv);

    qInstallMessageHandler(MessageOutput);

    MainFrame wnd;
    wnd.show();

    return app.exec();
}

主机.h:

#include <QMainWindow>

class QPushButton;
class MainFrame : public QMainWindow
{
    Q_OBJECT

public:
    MainFrame();

public slots:
    void showPopup();

private:
    QPushButton* button;
};

大型机.cpp:

#include "mainframe.h"

#include <QDialog>
#include <QLabel>
#include <QPushButton>
#include <QVBoxLayout>

MainFrame::MainFrame()
{
    QWidget* widget = new QWidget( this );
    widget->setLayout( new QVBoxLayout( widget ) );

    QPushButton* pTextButton = new QPushButton( "Show popup", widget );
    widget->layout()->addWidget( pTextButton );
    connect( pTextButton, SIGNAL(clicked()), this, SLOT(showPopup()) );

    setCentralWidget( widget );
}

void MainFrame::showPopup()
{
    QDialog dlg( this );
    dlg.setLayout( new QVBoxLayout() );
    dlg.layout()->addWidget( new QLabel("popup message",&dlg) );
    dlg.exec();
}

我在Windows 7和Windows 10下看到了这个问题。我做错什么了吗?

setMinimumSize (见 https://stackoverflow.com/a/31231069/3336423