[SOLVED] Running GUI application executable does not show the main window

johnsmith

I am trying to learn C++, Qt and QML by writing a simple app, but I am having trouble running the executable after I compile it. This is the code in main.cpp

#include <QtGui/QGuiApplication>
#include <QtQml/QQmlApplicationEngine>
#include <QtCore/QUrl>
#include <QtQml/QQmlContext>
#include <aboutappdialog.h>
#include <aboutqtdialog.h>

int main(int argc, char *argv[])
{
    QGuiApplication app(argc, argv);

    QQmlApplicationEngine engine;
    AboutAppDialog aboutApp;
    AboutQtDialog aboutQt;
    engine.rootContext()->setContextProperty("aboutApp", &aboutApp);
    engine.rootContext()->setContextProperty("aboutQt", &aboutQt);
    engine.load(QUrl(QStringLiteral("qrc:/main.qml")));

    return app.exec();
}

And this is the code of main.qml:

ApplicationWindow {
    id: mainWindow
    title: "MyApp"
    minimumHeight: 420
    minimumWidth: 420
    visibility: Window.AutomaticVisibility
    menuBar: MenuBar {
        Menu {
            title: qsTr("App")
            MenuItem {
                text: qsTr("New")
                shortcut: "Ctrl+N"
                onTriggered: Qt.quit() // change this
            }
            MenuItem {
                text: qsTr("Quit")
                shortcut: "Alt+F4"
                onTriggered: Qt.quit()
            }
        }
        Menu {
            title: qsTr("Tools")
            MenuItem {
                text: qsTr("Options")
                shortcut: "Ctrl+O"
                onTriggered: Qt.quit() //change this
            }
        }
        Menu {
            title: qsTr("About")
            MenuItem {
                text: qsTr("About Quick Tac Toe")
                onTriggered: { aboutApp = new AboutAppDialog(mainWindow);
                              aboutApp.aboutApp(mainWindow); }
            }
            MenuItem {
                text: qsTr("About Qt")
                onTriggered: { aboutQt = new AboutQtDialog(mainWindow);
                               aboutQt.aboutQt(mainWindow); }
            }
        }
    }
}

When I run the executable from the command line after building it, all I get is the following message: using qt5ct plugin

When I run qmlscene main.qml it does show the GUI as expected, but upon clicking the menu items for the "About" dialogs defined in C++, I get errors like this: ReferenceError: AboutAppDialog is not defined

So the question is simple: what am I doing wrong. Thanks in advance.

Paul H.

What if you add visible: true to main.qml?
Paul

johnsmith

@Paul-H. D'oh! Why, of course, how silly of me. visibility: Window.AutomaticVisibility does NOT automatically do visible: true.

Truly a case of needing to ask someone else to realize you're making a rookie mistake. Thanks for your help, Paul.