Solved Problems with QQmlViewer

[Blaster]

ello, I'm working on an application in QML for android, so I'm using the QQmlViewer to make use of the data types created by me, but I have a problem: when the application starts, I have to press the back button to be able to trigger the different components of my application. How can i fix this?

[SGaist]

Hi,

Without any code to analyse, it's going to be pretty difficult to help you.

[Blaster]

Sorry about that, Here is the code:

int main(int argc, char *argv[])
{
    QApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
    QApplication app(argc, argv);
    QQuickView viewer;
    viewer.setResizeMode(QQuickView::SizeRootObjectToView);

    SomeName somename;

    QQuickStyle::setStyle("Material");

    QQmlContext *context = viewer.rootContext();

    context->setContextProperty("SomeName", &somename);

    QObject::connect(viewer.engine(), &QQmlEngine::quit, &viewer, &QWindow::close);
    viewer.setSource(QUrl("qrc:/main.qml"));

    viewer.show();

    return app.exec();

}

[SGaist]

What do you have in your QML file ?

[Blaster]

This is all the code in my mail.qml file:

import QtQuick 2.6
import QtQuick.Controls 2.0
import QtQuick.Layouts 1.0
import Qt.labs.settings 1.0
import QtQuick.Controls.Material 2.0
import QtQuick.LocalStorage 2.0

ApplicationWindow {
    id: appwindow
    visible: true
    width: 340
    height: 480
    title: qsTr("RegCharge")


    Settings{
        id: settings
        property string style: "Material"
    }

    Loader{
        id: splashLoader
        anchors.fill: parent
        source: "qrc:/SplashScreen.qml"
    }

    header: ToolBar{
        Material.foreground: "white"
        Material.background: Material.Blue
        RowLayout{
            spacing: 20
            anchors.fill: parent


            ToolButton{
                id: hamButton
                contentItem: Image{
                    fillMode: Image.Pad
                    horizontalAlignment: Image.AlignHCenter
                    verticalAlignment: Image.AlignVCenter
                    source: "qrc:/Images/drawer.png"
                }
                onClicked: drawer.open()
            }

            Label{
                id: titleLabel
                text: "RegCharge"
                font.pixelSize: 20
                elide: Label.ElideRight
                horizontalAlignment: Qt.AlignHCenter
                verticalAlignment: Qt.AlignVCenter
                Layout.fillWidth: true
            }

            ToolButton{
                id: dotsButton
                contentItem: Image{
                    fillMode: Image.Pad
                    horizontalAlignment: Image.AlignHCenter
                    verticalAlignment: Image.AlignVCenter
                    source: "qrc:/Images/menu.png"
                }
                onClicked: optionsMenu.open()

                Menu{
                    id: optionsMenu
                    x: parent.width - width
                    transformOrigin: Menu.TopRight

                    MenuItem{
                        text: "About"
                        onTriggered: {
                            listView.currentIndex = listView.count - 1
                            titleLabel.text = "Acerca de"
                            stackView.replace("qrc:/About.qml")
                        }
                    }
                }
            }
        }
    }


    Drawer{
        id: drawer
        width: Math.min(appwindow.width, appwindow.height) / 3 * 2
        height: appwindow.height


        ListView{
            id: listView
            currentIndex: 0
            anchors.fill: parent

            delegate: ItemDelegate {
                width: parent.width
                text: model.title
                highlighted: ListView.isCurrentItem
                onClicked: {
                    if(listView.currentIndex != index){
                        listView.currentIndex = index
                        titleLabel.text = model.title
                        stackView.replace(model.source)
                    }
                    drawer.close()
                }
            }

            model: ListModel{
                id: listModel
                ListElement {title: "Principal"; source: "qrc:/Principal.qml" }
                ListElement {title: "DataBase"; source: "qrc:/DataBase.qml" }
                ListElement {title: "Estadística"; source: "qrc:/Statistic.qml" }
                ListElement {title: "Costos"; source: "qrc:/Costs.qml" }
                ListElement {title: "Acerca de"; source: "qrc:/About.qml"  }
            }
        }
    }

    StackView{
        id: stackView
        anchors.fill: parent
        
        ToolTip {
            id: toolTip
            timeout: 3000
            visible: Keys.onBackPressed()
            text: "Presione nuevamente para salir"
            Keys.onBackPressed:
            {
                Qt.quit()
            }
        }

        initialItem: Principal{}
        Component.onCompleted: {
            splashLoader.visible = false
        }
        Keys.onEscapePressed: console.log("Escape")
    }

    function createCostsTable() {
        var db = LocalStorage.openDatabaseSync("RegStore", "1.0", "RegStore Database", 5242880);

        db.transaction(
                    function(tx) {
                        tx.executeSql('CREATE TABLE IF NOT EXISTS Costs(Type integer, Valor double)');

                        var rs = tx.executeSql('SELECT * FROM Costs');

                        if(rs.rows.length <= 0)
                        {
                            var arr = [3, 5, 11, 14, 17, 22, 27]
                            var ar2 = [2.8, 4.8, 10, 13, 16.5, 20.8, 25.8]

                            for(var i = 0; i < arr.length; i++)
                            {
                                tx.executeSql('INSERT INTO Costs VALUES(?,?)', [arr[i], ar2[i]])
                            }
                            console.log("Correcto")
                        }
                    }
                    )
    }

    Component.onCompleted: createCostsTable()
}

[Blaster]

People, I solved the problem myself, although I really do not know what happens with QQmlViewer. In the end I used QQmlApplicationEngine , so the code was like this:

int main(int argc, char *argv[])
{
    QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
    QGuiApplication app(argc, argv);

    QQuickStyle::setStyle("Material");
    
    BackEnd backend;

    QQmlApplicationEngine engine;
    engine.rootContext()->setContextProperty("backEnd", &backend);
    engine.load(QUrl(QLatin1String("qrc:/main.qml")));

    return app.exec();
}