【QT源代码复用】QDateTimeEdit的下拉按钮事件响应

源码中的例子

    QStyleOptionComboBox optCombo;
    optCombo.init(this);
    optCombo.editable = true;
    optCombo.subControls = QStyle::SC_All;
    if(QStyle::SC_ComboBoxArrow == this->style()->hitTestComplexControl(QStyle::CC_ComboBox, &optCombo, event->pos(), this)) {

源码获取下拉窗口的位置

void QDateTimeEditPrivate::positionCalendarPopup()
{
    Q_Q(QDateTimeEdit);
    QPoint pos = (q->layoutDirection() == Qt::RightToLeft) ? q->rect().bottomRight() : q->rect().bottomLeft();
    QPoint pos2 = (q->layoutDirection() == Qt::RightToLeft) ? q->rect().topRight() : q->rect().topLeft();
    pos = q->mapToGlobal(pos);
    pos2 = q->mapToGlobal(pos2);
    QSize size = monthCalendar->sizeHint();
    QRect screen = QApplication::desktop()->availableGeometry(pos);
    //handle popup falling "off screen"
    if (q->layoutDirection() == Qt::RightToLeft) {
        pos.setX(pos.x()-size.width());
        pos2.setX(pos2.x()-size.width());
        if (pos.x() < screen.left())
            pos.setX(qMax(pos.x(), screen.left()));
        else if (pos.x()+size.width() > screen.right())
            pos.setX(qMax(pos.x()-size.width(), screen.right()-size.width()));
    } else {
        if (pos.x()+size.width() > screen.right())
            pos.setX(screen.right()-size.width());
        pos.setX(qMax(pos.x(), screen.left()));
    }
    if (pos.y() + size.height() > screen.bottom())
        pos.setY(pos2.y() - size.height());
    else if (pos.y() < screen.top())
        pos.setY(screen.top());
    if (pos.y() < screen.top())
        pos.setY(screen.top());
    if (pos.y()+size.height() > screen.bottom())
        pos.setY(screen.bottom()-size.height());
    monthCalendar->move(pos);
}