I want to show ListView with model, that is QVector of custom class. This question pretty much the same Qt QML C++ QList of structs as custom ListView model , but solution doesnt work for me. Here is a class, that contain fields. Signals and write-read autogenerated.
class Subject : public QObject
{
Q_OBJECT
public:
int First;
int Second;
explicit Subject(int fFirst = 0, int fSecond = 0, QObject *parent = nullptr)
{
this->First = fFirst;
this->Second = fSecond;
emit FirstChanged();
emit SecondChanged();
}
Subject::Subject(const Subject &Copy)
{
this->First = Copy.First;
this->Second = Copy.Second;
emit FirstChanged();
emit SecondChanged();
}
void Subject::operator=(const Subject &Right)
{
this->First = Right.First;
this->Second = Right.Second;
}
private:
Q_PROPERTY(int _First READ getFirst WRITE setFirst NOTIFY FirstChanged FINAL)
Q_PROPERTY(int _Second READ getSecond WRITE setSecond NOTIFY SecondChanged FINAL)
};
Here is a controller class
class Controller : public QObject
{
Q_OBJECT
public:
explicit Controller(QObject *parent = nullptr)
{
this->List.push_back(Subject(1, 0));
this->List.push_back(Subject(2, 0));
}
QVector<Subject> List;
QVector<Subject> getList() const;
void setList(const QVector<Subject> &newList);
Q_INVOKABLE void printAll();
private:
Q_PROPERTY(QVector<Subject> _List READ getList CONSTANT)
};
Qml main is Window with this
Controller
{
id: _Controller
Component.onCompleted:
{
_Controller.printAll()
}
}
ListView
{
anchors.fill: parent
model: _Controller._List
Component.onCompleted:
{
for (let i = 0; i < 2; i++)
{
console.log(_Controller._List[0])
}
}
delegate: Text {
id: _delegated
text: qsTr(modelData._First)
font.bold: true
color: "black"
font.pointSize: 24
}
}
I pretty much followed the solution, but i got nothing on my screen. The "List" is not empty on completed. Tried to change it to not const and emit ListChanged after app is running, but text not appearing. When I try to iterate through vector on ListView completed, like this
Component.onCompleted:
{
for (let i = 0; i < 2; i++)
{
console.log(_Controller._List)
}
}
Im getting this
qml: QVariant(QList<Subject>, )
qml: QVariant(QList<Subject>, )
There are a few bugs in your code. But with the following change as Accessing C++ QLists from QML suggested, the problem will be solved (Tested).
#include "subject.h"
class Controller : public QObject
{
Q_OBJECT
Q_PROPERTY(QVector<Subject*> _List READ getList CONSTANT)
public:
explicit Controller(QObject *parent = nullptr){
this->List.push_back(new Subject(1, 0));
this->List.push_back(new Subject(2, 0));
}
QVector<Subject*> List;
QVector<Subject*> getList() const{
return this->List;
}
};
The main takeaway is changing
QVector<Subject> _List
to
QVector<Subject*> _List
and some other changes that follows. Moreover, "Subject" and "Controller" class should be registered before loading the QML engine. Something like this:
int main(int argc, char *argv[])
{
QGuiApplication app(argc, argv);
qmlRegisterType<Controller>("Controller",1,0,"Controller");
qmlRegisterUncreatableType<Subject>("Subject",1,0,"Subject","Reference only");
QQmlApplicationEngine engine;
QObject::connect(&engine,engine.objectCreationFailed,&app,[&app](){app.exit(-1);});
engine.loadFromModule("Main","Main");
return app.exec();
}