It output nothing without error code!!

diuneiguohai

Thanks for reading. I am very new to qml.
It outputs nothing even the ui even when i comment out the whole testingtext.h!!
I do not know what happened. here is my code

.pro

QT += quick
QT += qml
CONFIG += c++11
CONFIG += qmltypes
QML_IMPORT_NAME = Charts
QML_IMPORT_MAJOR_VERSION = 1

# You can make your code fail to compile if it uses deprecated APIs.
# In order to do so, uncomment the following line.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \
        main.cpp \
        testingtext.cpp

RESOURCES += qml.qrc

TRANSLATIONS += \
    kpp_main_system_yue_HK.ts

# Additional import path used to resolve QML modules in Qt Creator's code model
QML_IMPORT_PATH =

# Additional import path used to resolve QML modules just for Qt Quick Designer
QML_DESIGNER_IMPORT_PATH =

# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target

HEADERS += \
    testingtext.h

main.cpp

#include <QGuiApplication>
#include <QQmlApplicationEngine>
#include <QDebug>
#include <QQmlContext>
#include "testingtext.h"

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

    qmlRegisterType<testingtext>("testingtext", 1, 0, "Testingtext");

    QQmlApplicationEngine engine;

    const QUrl url(QStringLiteral("qrc:/main.qml"));
    QObject::connect(&engine, &QQmlApplicationEngine::objectCreated,
                     &app, [url](QObject *obj, const QUrl &objUrl) {
        if (!obj && url == objUrl)
            QCoreApplication::exit(-1);
    }, Qt::QueuedConnection);
    engine.load(url);

    return app.exec();
}

textingtext.h

#include <QtQuick/QQuickPaintedItem>
#include <QString>
#include <QColor>
#include <QObject>

class testingtext : public QObject
{
    Q_OBJECT
    Q_PROPERTY(QString on9text MEMBER on9text NOTIFY on9textchanged)
    QML_ELEMENT

public:

    explicit testingtext(QObject *parent =nullptr);

signals:
    void on9textchanged();


private:
    QString text= "on9";



    QString on9text = "";
    void seton9text();


};

testingtext.cpp

#include "testingtext.h"

testingtext:: testingtext(QObject *parent): QObject(parent){

}

QString on9text(){
   return "on9";
}

main.qml

import QtQuick 2.15
import QtQuick.Controls 2.15
import testingtext 1.0

Item {
    id: root
    width:1280
    height: 720
    Rectangle {
        id: rectangle1

        color: "grey"
        anchors.fill: parent

        Testingtext {
            id: testingtext
        }

        RoundButton {
            id: button2
            x: 441
            y: 12
            width: 200
            height: 68
            radius: 8
            text: qsTr("Button")
            anchors.left: tab1.right
            anchors.top: tab1.top
            anchors.bottom: rectangle.top
            topPadding: 6
            anchors.bottomMargin: -6
            anchors.topMargin: 0
            anchors.leftMargin: 8
        }

        RoundButton {
            id: button1
            x: 600
            y: 12
            width: 200
            height: 68
            radius: 8
            text: qsTr("Button")
            anchors.left: tab1.right
            anchors.top: tab1.top
            anchors.bottom: rectangle.top
            topPadding: 6
            anchors.bottomMargin: -6
            anchors.topMargin: 0
            anchors.leftMargin: 8
        }


        RoundButton {
            id: button
            width: 200
            height: 68
            radius: 8
            text: qsTr("Button")
            anchors.left: button1.right
            anchors.bottom: rectangle.top
            anchors.leftMargin: 8
            anchors.bottomMargin: -8
            topPadding: 6
        }

        Rectangle {
            id: rectangle
            color: "#ffffff"
            radius: 20
            anchors.top: parent.top
            anchors.bottom: parent.bottom
            rotation: 0
            anchors.rightMargin: 16
            anchors.leftMargin: 16
            anchors.bottomMargin: 24
            anchors.topMargin: 72
            anchors.horizontalCenterOffset: 4
            anchors.horizontalCenter: parent.horizontalCenter

            TextInput {
                id: textInput
                x: 187
                y: 288
                width: 80
                height: 20
                text: testingtext.on9text
                font.pixelSize: 12
            }
        }

        Rectangle {
            id: tab1
            width: 200
            height: 200
            color: "#ffffff"
            radius: 8
            anchors.left: rectangle.left
            anchors.top: rectangle.top
            anchors.leftMargin: 0
            anchors.topMargin: -60
        }




    }



}

it is probaly a very dumb mistake that i cant spot!
Again! thanks for your time reading this!

Markkyboy

You're not making it easy on yourself or others who may be able to help. Although I'm not sure how to actually do it, you are better off putting your code on Github, making it easier for others to open your project rather than having to create the files individually.

Anyway, I did manually compile your code and got a ton of errors, now this could be because I compiled manually and made a mistake or two in doing so.

Having said the above, there maybe someone here on the forum with far more experience than myself and might spot your mistake/s, but honestly, put your code on Github for ease of access by others.

ODБOï

hi
@diuneiguohai said in It output nothing without error code!!:

main.qml

the root item in main.qml must be a Window or ApplicationWindow

diuneiguohai

@Markkyboy Thanks for your advice!!! will do next time

diuneiguohai

@LeLev Thanks! i changed the root to the applicationwindow type and it still does not output a window.

ODБOï

@diuneiguohai
did you set visible: true ?

diuneiguohai

Thank you so much!!! That was a very dumb mistake!!
I was wondering why people could also output window with root as a item type when i watched tutorial from few years back.
Is it purely because of the version of QtQuick?

ODБOï

@diuneiguohai said in It output nothing without error code!!:

I was wondering why people could also output window with root as a item type when i watched tutorial from few years back.

i don't know about it. Can you show an example ?