Starting QTimer In A QThread

I am trying to start a QTimer in a specific thread. However, the timer does not seem to execute and nothing is printing out. Is it something to do with the timer, the slot or the thread?

main.cpp

    #include "MyThread.h"
    #include <iostream>
    using namespace std;

    int main(int argc, char *argv[]) {
        MyThread t;
        t.start();
        while(1);
    }

MyThread.h

    #ifndef MYTHREAD_H
    #define MYTHREAD_H

    #include <QTimer>
    #include <QThread>
    #include <iostream>

    class MyThread : public QThread {
        Q_OBJECT
    public:
        MyThread();
    public slots:
        void doIt();
    protected:
        void run();
    };

    #endif  /* MYTHREAD_H */

MyThread.cpp

    #include "MyThread.h"

    using namespace std;

    MyThread::MyThread() {
        moveToThread(this);
    }

    void MyThread::run() {
        QTimer* timer = new QTimer(this);
        timer->setInterval(1);
        timer->connect(timer, SIGNAL(timeout()), this, SLOT(doIt()));
        timer->start();
    }

    void MyThread::doIt(){
        cout << "it works";
    }

As I commented (further information in the link) you are doing it wrong :

You are mixing the object holding thread data with another object (responsible of doIt()). They should be separated.
There is no need to subclass QThread in your case. Worse, you are overriding the run method without any consideration of what it was doing.

This portion of code should be enough

QThread* somethread = new QThread(this);
QTimer* timer = new QTimer(0); //parent must be null
timer->setInterval(1);
timer->moveToThread(somethread);
//connect what you want
somethread->start();

Now (Qt version >= 4.7) by default QThread starts a event loop in his run() method. In order to run inside a thread, you just need to move the object. Read the doc...

m_thread = new QThread(this);
QTimer* timer = new QTimer(0); // _not_ this!
timer->setInterval(1);
timer->moveToThread(m_thread);
// Use a direct connection to whoever does the work in order
// to make sure that doIt() is called from m_thread.
worker->connect(timer, SIGNAL(timeout()), SLOT(doIt()), Qt::DirectConnection);
// Make sure the timer gets started from m_thread.
timer->connect(m_thread, SIGNAL(started()), SLOT(start()));
m_thread->start();

A QTimer only works in a thread that has an event loop.

http://qt-project.org/doc/qt-4.8/QTimer.html

In multithreaded applications, you can use QTimer in any thread that has an event loop. To start an event loop from a non-GUI thread, use QThread::exec(). Qt uses the timer's thread affinity to determine which thread will emit the timeout() signal. Because of this, you must start and stop the timer in its thread; it is not possible to start a timer from another thread.

Starting QTimer In A QThread

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