QSpinBox/QDoubleSpinBox/QSlider组合使用

#define RULER_RATIO 100.0f
const int nMin = 10;
  const int nMax = 3000;
  const double dSingleStep = 0.01;
  QDoubleSpinBox *zoomSpinBox = new QDoubleSpinBox(this);
  zoomSpinBox->setRange(nMin / RULER_RATIO, nMax / RULER_RATIO);
  zoomSpinBox->setSingleStep(dSingleStep); //步长
  zoomSpinBox->setDecimals(2); //两位小数
    QSlider *zoomSlider = new QSlider(this);
    zoomSlider->setRange(nMin, nMax); //刻度滑块大小的取值范围;与宏定义RULER_RATIO紧密相连
    zoomSlider->setValue(RULER_RATIO);
    zoomSlider->setFixedWidth(200);
    zoomSlider->setToolTip(tr("调整帧的宽度"));
    zoomSlider->setOrientation(Qt::Horizontal);
    zoomSlider->setFocusPolicy(Qt::TabFocus);
//信号槽相互改变
  //如果微调框是int型
  //connect(zoomSpinBox, SIGNAL(valueChanged(int)), zoomSlider, SLOT(setValue(int)));
  //connect(zoomSlider, SIGNAL(valueChanged(int)), zoomSpinBox, SLOT(setValue(int)));
  //如果微调框是double型
  connect(zoomSpinBox, static_cast<void(QDoubleSpinBox::*)(double)>(&QDoubleSpinBox::valueChanged), zoomSlider, [=](double v)
  {
    zoomSlider->setValue(v * RULER_RATIO);
  });
  connect(zoomSpinBox, static_cast<void(QDoubleSpinBox::*)(const QString &)>(&QDoubleSpinBox::valueChanged), zoomSlider, [=](const QString &text)
  {
    //double d = zoomSpinBox->valueFromText(text);
    //小数转QString,保留2位小数
    //QString str = QString::number(d, 'f', 2);
  });
  //滑块
    connect(zoomSlider, &QSlider::valueChanged, mTracks, &TimeLineCells::setFrameSize);
    connect(zoomSlider, &QSlider::valueChanged, this, [=](int v) {
    zoomSpinBox->setValue(v / RULER_RATIO);
    });