I'm new to QT please help me with how to implement reactive programming in Qt

CodePudding user response：

There is a project called rqxt that you may want to look into. Check out the samples folder.

For example, this is a sample for signals and slots:

#include <QApplication>
#include <QDebug>
#include <QKeyEvent>
#include <QLineEdit>
#include <QPushButton>
#include <QVBoxLayout>
#include <QWidget>
#include <rxqt.hpp>

int main(int argc, char* argv[])
{
    QApplication a(argc, argv);

    auto widget = std::unique_ptr<QWidget>(new QWidget());
    auto layout = new QVBoxLayout;
    widget->setLayout(layout);
    {
        auto e0 = new QLineEdit("Edit here");
        auto e1 = new QLineEdit;
        e1->setEnabled(false);
        layout->addWidget(e0);
        layout->addWidget(e1);

        rxqt::from_signal(e0, &QLineEdit::textChanged)
            .map([](const QString& s) { return "[[["   s   "]]]"; })
            .subscribe([e1](const QString& s) { e1->setText(s); });

        rxqt::from_event(e0, QEvent::KeyPress)
            .subscribe([](const QEvent* e) {
                auto ke = static_cast<const QKeyEvent*>(e);
                qDebug() << ke->key();
            });
    }
    widget->show();
    return a.exec();
}

CodePudding user response：

If you want to use QML, then reactive programming will be very easy. Item properties in QML are naturally of reactive nature (just write a "java script" expression which uses other properties and the reactive connection will be established). Since Qt6, property bindings are available also in C , see https://www.youtube.com/watch?v=pN0pRBUqrrc

Moreover, you can use property bindings by KDAB https://www.kdab.com/signals-slots-properties-bindings/