Communication Between MainWindow & Thread class [Solved]

qt_sud

Hello Geeks,

I'm writing a sample application. I have a thread class. I m creating an instance of thread class in main window. I want to connect a main window signal to thread class slot. Below is my implementation.

Threadclass
@
class CThreadClass : public QThread
{
Q_OBJECT

public :
CThreadClass ();
~CThreadClass ();

private:
void run();

public slots:
void onUpdate(QString);

};
@

Main Window.h

@
signals:
void valueChanged(QString);

CThreadClass *     m_ptrMyThread;

@

Main Window.cpp
@
CMainWindow::CMainWindow(QWidget *parent)
: QMainWindow(parent)
, m_ptrMyThread(new CThreadClass())
, ui(new Ui::MainWindow)
{
ui->setupUi(this);
m_ptrMyThread->start();
connect(this, SIGNAL(valueChanged(QString)), m_ptrMyThread, SLOT(onUpdate(QString)));
}
@

I am emitting valueChanged inside a method. But the connected slot is never called.

Please let me know what is the wrong in my code.

Thank you.

poorBob

Hello,

where do You init the
@m_ptrMyThread@ pointer??

i.e. where do You have something like this:
@m_ptrMyThread = new CThreadClass()@
??

Maybe this is something what You are missing.

Another question: when You start the application, aren't there any console information about unsuccessful connections?

One more hint: I would start the thread after making all the needed connections.

with best regards,
poorBob

MohammadReza

Hello dear qt_sud

where did you emit signal in mainwindow class?

qt_sud

Hi PoorBob,

I am initializing m_ptrMyThread inside my constructor.

CMainWindow::CMainWindow(QWidget *parent)
: QMainWindow(parent)
, m_ptrMyThread(new CThreadClass())
, ui(new Ui::MainWindow)
{
ui->setupUi(this);
m_ptrMyThread->start();
connect(this, SIGNAL(valueChanged(QString)), m_ptrMyThread, SLOT(onUpdate(QString)));
}

qt_sud

Thank you all. I find the error. My signal name was missing after emit statment.

poorBob

Ok,

mark the post title with [SOLVED]

best wishes,
poorBob

MohammadReza

Glad to hear.