Call a slot whenever a QObject is created

TTIO

Hi,

I'm not so great at C++, so maybe I'm taking the wrong approach here, but I'm trying to make a garbage collector in QT. I've got most of it worked out, but I want to connect all instances of the onCreate() signal to a slot on said garbage collector, including those that haven't yet been made.

Is this possible? Is there a better approach?

Below is my header, for context. The idea is that it's a singleton which will be called whenever a page is pop()'d off my main StackView (at which point it will clear all items associated with said view).

#ifndef GARBAGECOLLECTOR_H
#define GARBAGECOLLECTOR_H

#include <QObject>
#include <QList>

class garbageCollector : public QObject
{
    Q_OBJECT
private:
    explicit garbageCollector(QObject *parent = nullptr);
    garbageCollector* instance;
    QList<QObject*>* objectList;

public:
    garbageCollector* getInstance();

signals:

public slots:
    void cleanup();
    void addItem();
};

#endif // GARBAGECOLLECTOR_H

sierdzio

Why do you need it? QML already contains a garbage collector. And all Q_OBJECT instances are additionally managed by parent-child hierarchy.

If you need some additional collecting, I'd rather recommend using QSharedPointer - it will automatically remove the object when needed, without any garbage collection class.

closx

Oh! Someone comes from Java development!

mrjj

Hi
There is already a system in place. as @sierdzio says
https://doc.qt.io/qt-5/objecttrees.html

So in most cases, ownership and clean up is handled by Qt.

TTIO

I do indeed come from Java :p
Or rather, python -> java -> now trying C++ and Rust.

So just to clarify, I'm in a situation where I might have several long-lived objects created by views in my stackview (C++ objects, that is). Despite that, by popping a view off said stackview, all the objects created by that view will be cleaned up, even if they're C++ objects (still derived from QObject)?