How to update the value of a struct using Q_PROPERTY and stylesheet?

Rua3n

In this example, I'm writting the "stylesheet" on a QTextEdit and applying it to the QMainWindow

myStruct.a: 10;
myStruct.b: "hello world";

setStyleSheet(textEdit->toPlainText());

I tried to follow this question:
https://forum.qt.io/topic/82325/best-way-to-access-a-cpp-structure-in-qml/6

But none of the functions is being called setA getA getMyStruct or setMyStruct when the stylesheet is applied.

What the proper way to update the values of MyStruct using the stylesheet?

struct MyStruct
{
    Q_GADGET
    int m_a;
    QString m_b;

    Q_PROPERTY(int a READ getA WRITE setA)
    Q_PROPERTY(QString b MEMBER m_b)

    void setA(int a) 
    { 
      m_a = a; 
    }
    int getA() const
    { 
        return m_a;
    }
};
Q_DECLARE_METATYPE(MyStruct)



class MainWindow : public QMainWindow
{
    Q_OBJECT
    Q_PROPERTY(MyStruct myStruct READ getMyStruct WRITE setMyStruct NOTIFY myStructChanged)
public:
    MainWindow() : QMainWindow(nullptr), ui(new Ui::MainWindow())
    {
        ui->setupUi(this);

        QVBoxLayout* layout = new QVBoxLayout();
        ui->centralWidget->setLayout(layout);

        QTextEdit* textEdit = new QTextEdit(this);
        textEdit->setText(R"(
            myStruct.a: 10;
            myStruct.b: "hello world";
        )");

        QPushButton* button = new QPushButton("update", this);
        connect(button, &QPushButton::clicked, [=] { setStyleSheet(textEdit->toPlainText()); });
        layout->addWidget(textEdit);
        layout->addWidget(button);
    }    

    MyStruct myStruct;

    MyStruct getMyStruct() const
    {
        return myStruct;
    }

    void setMyStruct(MyStruct val)
    {
        myStruct = val;
        emit myStructChanged();
    }

    void changeEvent(QEvent* event)
    {
        if (event->type() == QEvent::StyleChange) {	qDebug() << "style changed"; }
    }

signals:
    void myStructChanged();

private:
    Ui::MainWindow* ui;
};

Pl45m4

@Rua3n

it's quite old but look here

https://forum.qt.io/topic/53620/solved-set-dynamic-property-by-stylesheet

Rua3n

@Pl45m4 I read it but i still didn't understand what's wrong and how its related to a struct
The struct contains Q_PROPERTY

Rua3n

I wrote this based on; https://forum.qt.io/topic/82325/best-way-to-access-a-cpp-structure-in-qml/6
Why the struct is not getting called?

SGaist

Hi,

What is your goal exactly ? A stylesheet and QML are completely unrelated things.

Rua3n

@SGaist update the values of a struct from a stylesheet, is it possible?

struct MyStruct
{
     int b;
}

class Foo : public QObject
{
      Q_OBJECT
      Q_PROPERTY(int a MEMBER A)
      Q_PROPERTY(MyStruct myStruct MEMBER myStruct)
public:
      Foo();
      MyStruct myStruct;
      int a;
}

With this stylesheet, i can modify the value of a :

Foo
{
    qproperty-a: 10;
}

But how to modify b?

SGaist

I currently don't know if it's possible to use stylesheets to change the value of a gadget from a property.

However, can you please explain why you want to start altering such complex properties from within a stylesheet ?