QT Widget Subtype signalling

configdialog.cpp

typedef std::map<QString, std::variant<int, double, bool, QString>> DataType;
DataType activeData;

template<class T, typename X>
void ConfigDialog::updateActiveData(T widget, X value) {
  this->activeData[widget->objectName()] = value;
  qDebug() << value;
}


ConfigDialog::ConfigDialog(QWidget *parent)
    : QDialog(parent)
{
    QVBoxLayout *layout = new QVBoxLayout;
    QUiLoader loader;
    //Load from resource file
    QFile file(":/ui/ConfigDialog.ui");
    file.open(QIODevice::ReadOnly);
    if(file.error() != QFile::NoError) {
        qDebug() << file.error();
        return;
    }

    QWidget *myDialog = qobject_cast<QWidget*>(loader.load(&file));
    file.close();

    layout->addWidget(myDialog);
    setLayout(layout);

    //This is dirty, but QT doesn't make its underlying class accessible without casting
    //Any widgets not in this list will have to be added to be useable with the config.
    QList<QWidget *> widgets = this->findChildren<QWidget *>();

    //I am autolord, master of type inference. Requires C++14
    auto connector = [this] (auto _widget, auto _signal) {
        this->connect(_widget, _signal, this, [this, _widget] ( auto _value ) {
          this->updateActiveData(_widget, _value);
        });
    };
    auto editconnector = [this] (auto _widget, auto _signal) {
        this->connect(_widget, _signal, this, [this, _widget] () {
          this->updateActiveData(_widget, _widget->toPlainText());
        });
    };
    for(QWidget * widget : widgets ) {
        //Every widget for configs must have isconfigparameter in its properties.
        if(widget->property("isconfigparameter").toBool()) {
            if(auto _w = qobject_cast<QSlider *>(widget)) connector(_w, &QSlider::valueChanged);
            if(auto _w = qobject_cast<QLineEdit *>(widget)) connector(_w, &QLineEdit::textChanged);
            if(auto _w = qobject_cast<QCheckBox *>(widget)) connector(_w, &QCheckBox::toggled);
            //SpinBox has QString and int overloads. QT 5.7 has qOverload to choose one type.
            if(auto _w = qobject_cast<QSpinBox *>(widget)) connector(_w, qOverload<int>(&QSpinBox::valueChanged));
            if(auto _w = qobject_cast<QDial *>(widget)) connector(_w, &QDial::valueChanged);
            if(auto _w = qobject_cast<QProgressBar *>( widget)) connector(_w, &QProgressBar::valueChanged);
            if(auto _w = qobject_cast<QDoubleSpinBox *>( widget)) connector(_w, qOverload<double>(&QDoubleSpinBox::valueChanged));
            if(auto _w = qobject_cast<QComboBox *>( widget)) connector(_w, qOverload<const QString &>(&QComboBox::currentIndexChanged));
            //TextEdits are special in that their signal returns void, because why have conformance.
            if(auto _w = qobject_cast<QTextEdit *>( widget)) editconnector(_w, &QTextEdit::textChanged);
            if(auto _w = qobject_cast<QPlainTextEdit *>( widget)) editconnector(_w, &QPlainTextEdit::textChanged);
          }
    }
    //Only care about the QButtonGroup, not individual Radio Buttons.
    QList<QButtonGroup *> buttongroups = this->findChildren<QButtonGroup *>();
    for(QButtonGroup * group : buttongroups ) {
        this->connect(group, qOverload<QAbstractButton *, bool>(&QButtonGroup::buttonToggled), this, [this, group] (QAbstractButton * b, bool value) {
          if(value) this->updateActiveData(group, b->text());
        });
    }
}