Signals not working anymore after QObjects being moved into QThreads

Basically, the title... if there is no QThread (or it is just commented) I get the following result:

LOG> Log working!
LOG> PRODUCER: sent resource address: 29980624
PRODUCER: sent resource address: 29980624
CONSUMER: received resource address: 29980624


29980624, or any relevant memory position.

But, when un-commented just

LOG> Log working!


mainwindow.h

class MainWindow : public QMainWindow

Q_OBJECT

public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();

public slots:
void slot_log(QString str);

signals:
void signal_log(QString str);

private:
void createConsumer( void );
void deleteConsumer( void );
void createProducer( void );
void deleteProducer( void );
void createConnections( void );
SingleConsumer *consumer;
QThread *thread_consumer;
SingleProducer *producer;
QThread *thread_producer;
;


mainwindow.cpp

#include "mainwindow.h"

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent)

createConsumer();
createProducer();
createConnections();
QTimer::singleShot(1000, producer, SLOT(slot_publishResourceAddress()) );


void MainWindow::slot_log(QString str)

qWarning( QString("LOG> %1").arg(str).toUtf8() );


void MainWindow::createConnections( void )

connect(this, SIGNAL(signal_log(QString)), this, SLOT(slot_log(QString)));
emit signal_log(QString("Log working!"));

connect(producer, SIGNAL(signal_resourceAddress(uint_fast8_t*)), consumer, SLOT(slot_resource(uint_fast8_t*)));


void MainWindow::createProducer( void )

producer = new SingleProducer();
thread_producer = new QThread();
producer->moveToThread(thread_producer); // THIS LINE DESERVES ATTENTION
connect(producer, SIGNAL(signal_log(QString)), this, SLOT(slot_log(QString)));



singleproducer.h

#ifndef SINGLEPRODUCER_H
#define SINGLEPRODUCER_H

#include <QWidget>

class SingleProducer : public QObject

Q_OBJECT
public:
explicit SingleProducer(QObject *parent = nullptr);

signals:
void signal_resourceAddress( uint_fast8_t* addr );
void signal_log(QString str);
public slots:

void slot_publishResourceAddress( void )

emit signal_log( QString("PRODUCER: sent resource address: %1").arg((long int) &un_resources__) );
qWarning(QString("PRODUCER: sent resource address: %1").arg((long int) &un_resources__).toUtf8());
emit signal_resourceAddress( &un_resources__ );



private:
uint_fast8_t un_resources__;
;

#endif // SINGLEPRODUCER_H


The editor doesn't let me post more code... but I think that this is the most relevant part... if not, let me know. But I shared it at pastebin

Where is my mistake?

1 Answer
1

You forgot to actually start the QThreads after creating them in both MainWindow::createProducer and MainWindow::createConsumer. From the documentation of the constructor of QThread:

QThread

MainWindow::createProducer

MainWindow::createConsumer

QThread

Constructs a new QThread to manage a new thread. The parent takes ownership of the QThread. The thread does not begin executing until start() is called.

QThread

So all you need to do is call thread_producer->start() and thread_consumer->start() respectively after creating the threads.

thread_producer->start()

thread_consumer->start()

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