void ColorsListChoiceWidget::addNewRandomColor()
{
    QColor newColor0(rand() % 255, rand() % 255, rand() % 255);
    QColor newColor1(rand() % 255, rand() % 255, rand() % 255);
    addColorWidgetWithButton(newColor0, newColor1);
    emit colorListsChanged();
}
void UIPopupPane::paintBackground(const QRect &rect, QPainter &painter)
{
    /* Paint background: */
    QColor currentColor(palette().color(QPalette::Window));
    QColor newColor1(currentColor.red(), currentColor.green(), currentColor.blue(), opacity());
    QColor newColor2 = newColor1.darker(115);
    QLinearGradient headerGradient(rect.topLeft(), rect.bottomLeft());
    headerGradient.setColorAt(0, newColor1);
    headerGradient.setColorAt(1, newColor2);
    painter.fillRect(rect, headerGradient);
}