I can't connect signal QProcess::started() to a slot

[Petruza]

Hi, I'm starting with QT, I try to connect a slot to signal QProcess::started() but can't. QObject::connect() returns false.
Any idea what am I doing wrong?

Here's part of the code:

class foo : public QObject
{    
 public:
  QProcess *process;
 
 public slots:
  void process_started();
}
 
foo::foo()
{
 process = new QProcess();
 bool status = QObject::connect( process, SIGNAL( started() ), this, SLOT( process_started() ) );
 // status is false, meaning the slot and signal couldn't be connected
}

class foo : public QObject
{    
 public:
  QProcess *process;

 public slots:
  void process_started();
}

foo::foo()
{
 process = new QProcess();
 bool status = QObject::connect( process, SIGNAL( started() ), this, SLOT( process_started() ) );
 // status is false, meaning the slot and signal couldn't be connected
}

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I know the process starts successfully because I tried process->WaitForStarted() and it returns true.
But I put a breakpoint at the slot foo::process_started() and it never gets hit.
What's the problem here?
Thanks!

[yogeshgokul]

Please write this Q_OBJECT macro in your class declaration. Like this.

class foo : public QObject
{    
Q_OBJECT 
public:
  QProcess *process;
 
 public slots:
  void process_started();
}
 
foo::foo()
{
 process = new QProcess();
 bool status = connect( process, SIGNAL( started() ), this, SLOT( process_started() ) );// Removed QObject::
 // status is false, meaning the slot and signal couldn't be connected
}

class foo : public QObject
{    
Q_OBJECT 
public:
  QProcess *process;

 public slots:
  void process_started();
}

foo::foo()
{
 process = new QProcess();
 bool status = connect( process, SIGNAL( started() ), this, SLOT( process_started() ) );// Removed QObject::
 // status is false, meaning the slot and signal couldn't be connected
}

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[spirit]

...and rerun qmake & make.

[Petruza]

Thanks Autobot, you're right!
About qmake, I'll let QTcreator handle it
Although QTcreator is pretty slow, don't you think?

[yogeshgokul]

Thanks Autobot

!! VOILA !!

Although QTcreator is pretty slow, don't you think?

If you compare it with VS then yes.

[Petruza]

I hope it's not slow because it's built with QT
In your experience, applications made with QT are slow? do they have other downside?

[yogeshgokul]

I hope it's not slow because it's built with QT

Not at all. Its slow on windows because its compiler and debugger(=GDB) is slow. Creator can be used with MSVC on Windows, too – even for debugging.

In your experience, applications made with QT are slow? do they have other downside?

No they are fast enough. Coz C++ is fast.

[Petruza]

Creator can be used with MSVC on Windows, too – even for debugging.

So I've read, I'll try it.
There's a QT plugin for MSVC right?

[yogeshgokul]

Yes.. !