Learn QT-WEBASSEMBLY with Real Code Examples

#include <QApplication>
#include <QWidget>
#include <QPushButton>
#include <QLabel>
#include <QVBoxLayout>

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    QWidget window;
    window.setWindowTitle("Qt WebAssembly Counter");

    int count = 0;
    QLabel *label = new QLabel(QString("Counter: %1").arg(count));
    QPushButton *btnIncrement = new QPushButton("+");
    QPushButton *btnDecrement = new QPushButton("-");
    QPushButton *btnReset = new QPushButton("Reset");

    QVBoxLayout *layout = new QVBoxLayout;
    layout->addWidget(label);
    layout->addWidget(btnIncrement);
    layout->addWidget(btnDecrement);
    layout->addWidget(btnReset);
    window.setLayout(layout);

    QObject::connect(btnIncrement, &QPushButton::clicked, [&](){
        count++;
        label->setText(QString("Counter: %1").arg(count));
    });

    QObject::connect(btnDecrement, &QPushButton::clicked, [&](){
        count--;
        label->setText(QString("Counter: %1").arg(count));
    });

    QObject::connect(btnReset, &QPushButton::clicked, [&](){
        count = 0;
        label->setText(QString("Counter: %1").arg(count));
    });

    window.show();
    return app.exec();
}

Demonstrates a simple counter layout using Qt Widgets and C++ compiled to WebAssembly for browser interactivity.

#include <QApplication>
#include <QWidget>
#include <QLabel>

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    QWidget window;
    window.setWindowTitle("Hello Qt WebAssembly");

    QLabel *label = new QLabel("Hello, WebAssembly!");
    label->setAlignment(Qt::AlignCenter);

    window.setFixedSize(300, 200);
    label->setParent(&window);
    window.show();
    return app.exec();
}

Displays a simple 'Hello World' label in a Qt WebAssembly browser app.

#include <QApplication>
#include <QWidget>
#include <QPushButton>
#include <QLabel>
#include <QVBoxLayout>

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    QWidget window;
    window.setWindowTitle("Button Click Example");

    QLabel *label = new QLabel("Button not clicked");
    QPushButton *button = new QPushButton("Click Me");

    QVBoxLayout *layout = new QVBoxLayout;
    layout->addWidget(label);
    layout->addWidget(button);
    window.setLayout(layout);

    QObject::connect(button, &QPushButton::clicked, [&](){
        label->setText("Button Clicked!");
    });

    window.show();
    return app.exec();
}

A simple button click event example for Qt WebAssembly.

#include <QApplication>
#include <QWidget>
#include <QLineEdit>
#include <QLabel>
#include <QVBoxLayout>
#include <QString>

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    QWidget window;
    window.setWindowTitle("Text Input Example");

    QLineEdit *lineEdit = new QLineEdit();
    QLabel *label = new QLabel("Enter text above");

    QVBoxLayout *layout = new QVBoxLayout;
    layout->addWidget(lineEdit);
    layout->addWidget(label);
    window.setLayout(layout);

    QObject::connect(lineEdit, &QLineEdit::textChanged, [&](const QString &text){
        label->setText("You typed: " + text);
    });

    window.show();
    return app.exec();
}

Captures user input from a text box and displays it.

#include <QApplication>
#include <QWidget>
#include <QSlider>
#include <QLabel>
#include <QVBoxLayout>
#include <Qt>

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    QWidget window;
    window.setWindowTitle("Slider Example");

    QLabel *label = new QLabel("Value: 0");
    QSlider *slider = new QSlider(Qt::Horizontal);
    slider->setRange(0, 100);

    QVBoxLayout *layout = new QVBoxLayout;
    layout->addWidget(label);
    layout->addWidget(slider);
    window.setLayout(layout);

    QObject::connect(slider, &QSlider::valueChanged, [&](int value){
        label->setText("Value: " + QString::number(value));
    });

    window.show();
    return app.exec();
}

Demonstrates a slider controlling a label value.

#include <QApplication>
#include <QWidget>
#include <QPushButton>
#include <QVBoxLayout>
#include <QString>

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    QWidget window;
    window.setWindowTitle("Toggle Button Example");

    QPushButton *button = new QPushButton("OFF");
    QVBoxLayout *layout = new QVBoxLayout();
    layout->addWidget(button);
    window.setLayout(layout);

    QObject::connect(button, &QPushButton::clicked, [=]() mutable {
        if(button->text() == "OFF") button->setText("ON");
        else button->setText("OFF");
    });

    window.show();
    return app.exec();
}

A toggle button changes the text between ON and OFF.

#include <QApplication>
#include <QWidget>
#include <QPushButton>
#include <QLabel>
#include <QVBoxLayout>
#include <QPalette>

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    QWidget window;
    window.setWindowTitle("Color Change Example");

    QLabel *label = new QLabel("Watch my color");
    QPushButton *button = new QPushButton("Change Color");

    QVBoxLayout *layout = new QVBoxLayout();
    layout->addWidget(label);
    layout->addWidget(button);
    window.setLayout(layout);

    QObject::connect(button, &QPushButton::clicked, [=]() {
        QPalette pal = label->palette();
        pal.setColor(QPalette::WindowText, Qt::red);
        label->setPalette(pal);
    });

    window.show();
    return app.exec();
}

Changes label color on button click.

#include <QApplication>
#include <QWidget>
#include <QCheckBox>
#include <QLabel>
#include <QVBoxLayout>

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    QWidget window;
    window.setWindowTitle("Checkbox Example");

    QCheckBox *checkBox = new QCheckBox("Check me");
    QLabel *label = new QLabel("Unchecked");

    QVBoxLayout *layout = new QVBoxLayout();
    layout->addWidget(checkBox);
    layout->addWidget(label);
    window.setLayout(layout);

    QObject::connect(checkBox, &QCheckBox::stateChanged, [&](int state){
        label->setText(state == Qt::Checked ? "Checked" : "Unchecked");
    });

    window.show();
    return app.exec();
}

A checkbox toggles a label between checked and unchecked.

#include <QApplication>
#include <QWidget>
#include <QSlider>
#include <QProgressBar>
#include <QVBoxLayout>
#include <Qt>

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    QWidget window;
    window.setWindowTitle("Progress Bar Example");

    QSlider *slider = new QSlider(Qt::Horizontal);
    QProgressBar *progress = new QProgressBar();
    slider->setRange(0, 100);
    progress->setRange(0, 100);

    QVBoxLayout *layout = new QVBoxLayout();
    layout->addWidget(slider);
    layout->addWidget(progress);
    window.setLayout(layout);

    QObject::connect(slider, &QSlider::valueChanged, [&](int value){
        progress->setValue(value);
    });

    window.show();
    return app.exec();
}

Updates a progress bar based on a slider value.