Static lib - SIGNAL/SLOT

[ODБOï]

I have created a static lib with qt, a simple QObject derived class.
Can my static lib be a QObject derived class and have Signal/Slots working ?

im able to use my lib in another project but cant connect to the signals emited

 CN16K_SFTP sftp; // lib object

    sftp.connectToMachine(QString("user@10.81.100.100")); // method call works
    QObject::connect(&sftp,&CN16K_SFTP::errMsgChanged,this,&SftpUser::handleSftpMessage); // handleSftpMessage is never called

[VRonin]

@LeLev said in Static lib - SIGNAL/SLOT:

handleSftpMessage is never called

Since you are allocating sftp on the stack, are you sure it survives long enough to emit the signal in the first place?

[ODБOï]

@VRonin thank you,
I was creating sftp in the constructor, now i moved it as member variable, but the handler slot is still not called

[VRonin]

Can you show the entire code? did you remove CN16K_SFTP sftp; // lib object from the constructor?

[ODБOï]

@VRonin no i'm not removing it

#ifndef SFTPUSER_H
#define SFTPUSER_H

#include <QObject>
#include "cn16k_sftp.h"

class SftpUser : public QObject
{
    Q_OBJECT
public:
    explicit SftpUser(QObject *parent = nullptr);
signals:
public slots:
    void handleSftpMessage(QString msg){
        qDebug()<<"Sftp Messages handeled : " << msg;
    }
private:
      CN16K_SFTP m_sftp;
};

#endif // SFTPUSER_H

// .cpp

SftpUser::SftpUser(QObject *parent) : QObject(parent)
{
    m_sftp.connectToMachine(QString("user@10.81.100.100"));
    QObject::connect(&m_sftp,&CN16K_SFTP::errMsgChanged,this,&SftpUser::handleSftpMessage);
}

[Christian Ehrlicher]

I would move the connect above the call to connectToMachine()

[VRonin]

Also, stupid question: are you creating a SftpUser object anywhere?

[ODБOï]

@Christian-Ehrlicher Hi, thank you but i don't understand what do you mean,
the class i pasted is part of simple qtQuick project, in that project im linking to a static lib i created

the CN16K_SFTP m_sftp; is that object. It has a method connectToMachine, when connexion is ok a signal is emited.

Now my app just creats a CN16K_SFTP object , uses connectToMachine(), and need to listen the signal, everithing works but signal is not handled.

@VRonin yes, because i i said i'm sure that the connexion is etablished and the signal is emitted,
i create the SftpUser in my apps main.cpp

 SftpUser sftp;
    QQmlApplicationEngine engine;
    engine.rootContext()->setContextProperty("sftp",&sftp);

[VRonin]

@LeLev said in Static lib - SIGNAL/SLOT:

Hi, thank you but i don't understand what do you mean,

He means change

m_sftp.connectToMachine(QString("user@10.81.100.100"));
QObject::connect(&m_sftp,&CN16K_SFTP::errMsgChanged,this,&SftpUser::handleSftpMessage);

to

QObject::connect(&m_sftp,&CN16K_SFTP::errMsgChanged,this,&SftpUser::handleSftpMessage);
m_sftp.connectToMachine(QString("user@10.81.100.100"));

[ODБOï]

@Christian-Ehrlicher , @VRonin that worked ! thank you very much