Qt: How to implement QDialogButtonBox with QSignalMapper for non-standard button ??

Question

I have a QDialogButtonBox with All Standard Button and Non Standard Buttons (QPushbutton added to create Non-Standard Buttons).

I can implement SignalMapper saperately f

Answer 1

QSignalMapper can map a QObject and a integer. So you can map your non-standardButton with its role and create a slot that takes in parameter a role:

For example:

void Widget::initMap() {
     QPushButton* buttonReset = new QPushButton( "Reset" );
     signalMapper = new QSignalMapper(this);
     connect(buttonReset, SIGNAL(clicked()), signalMapper, SLOT(map()));
     signalMapper->setMapping(button, QDialogButtonBox::ResetRole);
     connect(signalMapper, SIGNAL(mapped(int)), this, SLOT(slot(int)));
}

void Widget::slot( int role) {
    if ( role == QDialogButtonBox::ResetRole ) {
        reset();
    } else if ( QDialogButtonBox::Apply ) {
        apply();
    }
}

Answer 2

You shouldn't need to use QSignalMapper with QDialogButtonBox.

QSignalMapper is used to connect multiple signals to a single slot, and QDialogButtonBox already has a single signal that is emitted for all the buttons: clicked(QAbstractButton*).

You could simply assign a value to the button with a map (QMap, std::map) or through a dynamic property:

enum { MyRole1 = 1, MyRole2 }; // starting at 1 because an unset property would return 0
...
userButton−>setProperty("ActionRole", MyRole1); // a cast to int might be needed here
buttonBox->addButton(userButton, QDialogButtonBox::ActionRole);

connect(this, SIGNAL(clicked(QAbstractButton*)), SLOT(dialogButtonClicked(QAbstractButton *button)));

And in the slot, you would get the value back from the parameter passed by the signal:

void MyClass::dialogButtonClicked(QAbstractButton *button) {
    StandardButton standardButton = buttonBox−>standardButton(button);
    switch(standardButton) {
    // Standard buttons:
    case QDialogButtonBox::Ok: 
        ... 
        break;
    case QDialogButtonBox::Abort: 
        ...
        break;

    // Non-standard buttons:
    case QDialogButtonBox::NoButton: 
       int actionRole = button->property("ActionRole").toInt();
       switch(actionRole) {
       case MyRole1: 
           ...
           break;
       case MyRole2: 
           ...
           break;
      default:
           // shouldn't happen
           break; 
       }

    }
}