Qt纯用代码写一个左右滑动开关按钮，添加到界面

好的，我可以为你提供一个基于Qt代码的左右滑动开关按钮的实现方法。

首先，我们需要在Qt的工程中添加一个自定义控件类。创建一个名为`SlideSwitch`的类，继承自`QWidget`，并在`.h`文件中添加以下代码：

class SlideSwitch : public QWidget
{
    Q_OBJECT

public:
    explicit SlideSwitch(QWidget *parent = nullptr);
    void setSwitchColor(const QColor &color);

protected:
    void paintEvent(QPaintEvent *event) override;
    void mousePressEvent(QMouseEvent *event) override;
    void mouseMoveEvent(QMouseEvent *event) override;
    void mouseReleaseEvent(QMouseEvent *event) override;

private:
    QColor m_switchColor;
    bool m_isOn;
    QPoint m_dragPos;
};

然后，在`.cpp`文件中实现这些函数：

SlideSwitch::SlideSwitch(QWidget *parent) : QWidget(parent)
{
    setFixedSize(60, 30);
    m_switchColor = QColor(0, 150, 136);
    m_isOn = false;
}

void SlideSwitch::setSwitchColor(const QColor &color)
{
    m_switchColor = color;
    update();
}

void SlideSwitch::paintEvent(QPaintEvent *event)
{
    QPainter painter(this);
    painter.setRenderHint(QPainter::Antialiasing, true);

    QRectF bgRect(0, 0, width(), height());
    QRectF switchRect(0, 0, height(), height());
    switchRect.moveLeft(m_isOn ? width() - height() : 0);

    QBrush bgBrush(QColor(220, 220, 220));
    painter.setBrush(bgBrush);
    painter.setPen(Qt::NoPen);
    painter.drawRoundedRect(bgRect, height() / 2, height() / 2);

    QBrush switchBrush(m_switchColor);
    painter.setBrush(switchBrush);
    painter.drawEllipse(switchRect);

    QWidget::paintEvent(event);
}

void SlideSwitch::mousePressEvent(QMouseEvent *event)
{
    m_dragPos = event->pos();
}

void SlideSwitch::mouseMoveEvent(QMouseEvent *event)
{
    if (event->buttons() & Qt::LeftButton) {
        int distance = event->pos().x() - m_dragPos.x();
        if (m_isOn) {
            if (distance < 0) {
                m_isOn = false;
                update();
            }
        } else {
            if (distance > 0) {
                m_isOn = true;
                update();
            }
        }
    }
}

void SlideSwitch::mouseReleaseEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton) {
        int distance = event->pos().x() - m_dragPos.x();
        if (m_isOn) {
            if (distance < 0) {
                m_isOn = false;
                update();
            }
        } else {
            if (distance > 0) {
                m_isOn = true;
                update();
            }
        }
    }
}

最后，在你的界面中使用这个自定义控件：

SlideSwitch *switchButton = new SlideSwitch(this);
switchButton->setGeometry(10, 10, 60, 30);

这样就完成了一个左右滑动开关按钮的实现啦！