title: How to connect a QSlider to QDoubleSpinBox
body: <p>I want to connect a QSlider to a QDoubleSpinBox but while the code compiles fine and runs for simple QSpinBox, it doesn't work for QDoubleSpinBox</p>
  
  <pre><code>QSlider *horizontalSlider1 = new QSlider();
  QDoubleSpinBox *spinBox1 = new QDoubleSpinBox();
  
  connect(spinBox1, SIGNAL(valueChanged(double)),horizontalSlider1,SLOT(setValue(double)) );
  connect(horizontalSlider1,SIGNAL(valueChanged(double)),spinBox1,SLOT(setValue(double)) );
  </code></pre>