Qt setCursor issue after leaveEvent - c++

Question

I am using the QWidget::setCursor method, but after a QMessageBox popup, in some cases it temporarily reverts to the old cursor (until I cause it to "refresh" and load the override cursor again).
The pattern seems to be that if you exit the message box with the cursor outside of its frame (for example, use the Escape key), then the cursor is gone. On the other hand, if you exit the message box with the cursor inside its frame, then the override cursor returns.
I have tried to debug it myself by subclassing QWidget and overriding enterEvent and leaveEvent. Interestingly, when the dialog box appears, a leaveEvent is triggered on the main widget, but the next enterEvent is triggered only if the cursor was inside the message box frame when closing the dialog. Otherwise, no enterEvent is seen.
How can I get that the override cursor is always returned?
Header file:
#include <QtWidgets>
class Widget : public QWidget {
Q_OBJECT
public:
Widget(QWidget *parent = 0);
void enterEvent(QEvent *);
void leaveEvent(QEvent *);
};
class MainWindow : public QMainWindow {
Q_OBJECT
public:
MainWindow(QWidget *parent = 0);
public slots:
void popup();
};
Source file:
#include <QtWidgets>
#include "main.h"
Widget::Widget(QWidget *parent) : QWidget(parent) { }
void Widget::enterEvent(QEvent * e) {
puts("Widget::enterEvent"); QWidget::enterEvent(e);
}
void Widget::leaveEvent(QEvent * e) {
puts("Widget::leaveEvent"); QWidget::leaveEvent(e);
}
MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent) {
Widget * widget = new Widget(this);
widget->setMinimumSize(500, 500);
widget->setCursor(Qt::CrossCursor);
setCentralWidget(widget);
connect(new QShortcut(QKeySequence("A"),this),SIGNAL(activated()),
this,SLOT(popup()));
}
void MainWindow::popup() {
QMessageBox::question(
this, "Test", "Test", QMessageBox::Yes|QMessageBox::No);
}
int main(int argc, char *argv[]) {
QApplication app(argc,argv);
MainWindow thewindow;
thewindow.show();
int re = app.exec();
return re;
}