分享按钮组实现小例子

QButtonGroup *buttonGroup = new QButtonGroup(this);
/* 监听ButtonGroup按钮事件 */
connect(buttonGroup, SIGNAL(buttonClicked(int)), this, SLOT(onClicked(int)));

QList<QColor> colorList;
colorList << "red"
          << "green"
          << "blue"
          << "yellow"
          << "black"
          << "white";

foreach (const QColor &color, colorList) {
    QPushButton *colorButton = new QPushButton(this);
    colorButton->setFixedSize(100, 100);

    /* 设置为单项选择 */
    colorButton->setCheckable(true);

    /* 画图标的颜色 */
    QPixmap colorPixmap = QPixmap(20, 20);
    QPainter painter;
    painter.begin(&colorPixmap);
    painter.fillRect(QRectF(0, 0, 20, 20),
                     QColor(color));
    painter.end();

    /* 设置按钮的图标 */
    QIcon colorIcon = QIcon(colorPixmap);
    colorButton->setIcon(colorIcon);

    /* 添加按钮到QButtonGroup中 */
    buttonGroup->addButton(colorButton, color.rgb());
}

QToolBar *toolBar = new QToolBar(this);
/* 将工具栏添加到QToolBar中 */
foreach (QAbstractButton *button, buttonGroup->buttons()) {
    toolBar->addWidget(button);
}

/* 工具栏样式 */
toolBar->setStyleSheet(R"(
                       QToolBar {
                           border-style: solid;
                           border-radius: 5px;
                           margin: 0px;
                           padding: 0px;
                           color: white;
                           background: white;
                       })");

toolBar->resize(toolBar->sizeHint());