slint/examples/cpp/qt_viewer/qt_viewer.cpp

// Copyright © SixtyFPS GmbH <info@slint.dev>
// SPDX-License-Identifier: MIT

#include <QtWidgets/QtWidgets>
#include <slint-interpreter.h>

#include "ui_interface.h"

struct LoadedFile
{
    slint::ComponentHandle<slint::interpreter::ComponentInstance> instance;
    QWidget *widget;
};

void show_diagnostics(QWidget *root,
                      const slint::SharedVector<slint::interpreter::Diagnostic> &diags)
{
    QString text;

    for (auto diagnostic : diags) {
        text += (diagnostic.level == slint::interpreter::DiagnosticLevel::Warning
                         ? QApplication::translate("qt_viewer", "warning: %1\n")
                         : QApplication::translate("qt_viewer", "error: %1\n"))
                        .arg(QString::fromUtf8(diagnostic.message.data()));

        text += QApplication::translate("qt_viewer", "location: %1")
                        .arg(QString::fromUtf8(diagnostic.source_file.data()));
        if (diagnostic.line > 0)
            text += ":" + QString::number(diagnostic.line);
        if (diagnostic.column > 0)
            text += ":" + QString::number(diagnostic.column);
        text += "\n";
    }

    QMessageBox::critical(root, QApplication::translate("qt_viewer", "Compilation error"), text,
                          QMessageBox::StandardButton::Ok);
}

int main(int argc, char **argv)
{
    QApplication app(argc, argv);
    QWidget main;
    Ui::Interface ui;
    ui.setupUi(&main);
    QHBoxLayout layout(ui.my_content);

    std::unique_ptr<LoadedFile> loaded_file;
    slint::interpreter::Value::Type currentType;

    auto load_file = [&](const QString &fileName) {
        loaded_file.reset();
        slint::interpreter::ComponentCompiler compiler;
        auto def = compiler.build_from_path(fileName.toUtf8().data());
        if (!def) {
            show_diagnostics(&main, compiler.diagnostics());
            return;
        }
        auto instance = def->create();
        QWidget *wid = instance->qwidget();
        if (!wid) {
            QMessageBox::critical(&main, QApplication::translate("qt_viewer", "No Qt backend"),
                                  QApplication::translate(
                                          "qt_viewer", "Slint is not running with the Qt backend."),
                                  QMessageBox::StandardButton::Ok);
            return;
        }
        wid->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
        layout.addWidget(wid);
        loaded_file = std::make_unique<LoadedFile>(LoadedFile { instance, wid });
    };

    auto args = app.arguments();
    if (args.count() == 2) {
        load_file(args.at(1));
    }

    QObject::connect(ui.load_button, &QPushButton::clicked, [&] {
        QString fileName = QFileDialog::getOpenFileName(
                &main, QApplication::translate("qt_viewer", "Open Slint File"), {},
                QApplication::translate("qt_viewer", "Slint File (*.slint)"));
        if (fileName.isEmpty())
            return;
        load_file(fileName);
    });

    QObject::connect(ui.prop_name, &QLineEdit::textChanged, [&] {
        if (!loaded_file)
            return;
        if (auto val = loaded_file->instance->get_property(ui.prop_name->text().toUtf8().data())) {
            currentType = val->type();
            switch (currentType) {
            case slint::interpreter::Value::Type::String:
                ui.prop_value->setText(QString::fromUtf8(val->to_string()->data()));
                break;

            case slint::interpreter::Value::Type::Number:
                ui.prop_value->setText(QString::number(*val->to_number()));
                break;

            case slint::interpreter::Value::Type::Bool:
                ui.prop_value->setText(*val->to_number() ? "true" : "false");
                break;

            default:
                ui.prop_value->clear();
                break;
            }
        }
    });

    QObject::connect(ui.set_button, &QPushButton::clicked, [&] {
        if (!loaded_file)
            return;
        slint::interpreter::Value val;
        switch (currentType) {
        case slint::interpreter::Value::Type::String:
            val = slint::SharedString(ui.prop_value->text().toUtf8().data());
            break;
        case slint::interpreter::Value::Type::Number: {
            bool ok;
            val = ui.prop_value->text().toDouble(&ok);
            if (!ok) {
                QMessageBox::critical(
                        &main, QApplication::translate("qt_viewer", "Set Property Error"),
                        QApplication::translate("qt_viewer", "Invalid conversion to number"),
                        QMessageBox::StandardButton::Ok);
                return;
            }
            break;
        }
        case slint::interpreter::Value::Type::Bool: {
            if (ui.prop_value->text() == "true") {
                val = true;
            } else if (ui.prop_value->text() == "false") {
                val = false;
            } else {
                QMessageBox::critical(
                        &main, QApplication::translate("qt_viewer", "Set Property Error"),
                        QApplication::translate(
                                "qt_viewer",
                                "Invalid conversion to boolean, must be true or false"),
                        QMessageBox::StandardButton::Ok);
                return;
            }
            break;
        }
        default:
            QMessageBox::critical(
                    &main, QApplication::translate("qt_viewer", "Set Property Error"),
                    QApplication::translate("qt_viewer", "Cannot set properties of this type"),
                    QMessageBox::StandardButton::Ok);
            return;
        }
        if (!loaded_file->instance->set_property(ui.prop_name->text().toUtf8().data(), val)) {
            QMessageBox::critical(&main, QApplication::translate("qt_viewer", "Set Property Error"),
                                  QApplication::translate("qt_viewer", "Could not set property"),
                                  QMessageBox::StandardButton::Ok);
        }
    });

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