Prevent Firing Signals in Qt

Question

We have a QCheckBox object, when user checks it or removes check we want to call a function so we connect our function to stateChanged ( int state )

Answer 1

Even in QT5, its a bit cumbersome when there are many/several things to block. Here's a multi-object version that is concise to use:

class SignalBlocker
{
public:
  SignalBlocker(QObject *obj)
  {
    insert( QList()<  objects)
  {
    insert(objects);
  }    
  void insert(QList  objects)
  {
    for (auto obj : objects)
      m_objs.insert(obj, obj->signalsBlocked());
    blockAll();
  }    
  void blockAll() {
    for( auto m_obj : m_objs.keys() )
      m_obj->blockSignals(true);
  }    
  ~SignalBlocker()
  {
    for( auto m_obj : m_objs.keys() )
      m_obj->blockSignals( m_objs[m_obj] );
  }    
private:
  QMap m_objs;      
};

usage:

void SomeType::myFunction()
{
    SignalBlocker tmp( QList() 
    << m_paramWidget->radioButton_View0
    << m_paramWidget->radioButton_View1
    << m_paramWidget->radioButton_View2
    );
    // Do more work, ... 
}