Hi,
Signal and slot was associated using the QtUi. The generated code for Vehicle data is pasted below.

ehicleSpeedDisplay = new QSlider(SpeedDisplaygroupBox);
VehicleSpeedDisplay->setObjectName(QStringLiteral("VehicleSpeedDisplay "));
VehicleSpeedDisplay->setGeometry(QRect(10, 90, 161, 31));
VehicleSpeedDisplay->setInputMethodHints(Qt::ImhNone);
VehicleSpeedDisplay->setMaximum(250);
VehicleSpeedDisplay->setSingleStep(5);
VehicleSpeedDisplay->setPageStep(5);
VehicleSpeedDisplay->setValue(60);
VehicleSpeedDisplay->setTracking(true);
VehicleSpeedDisplay->setOrientation(Qt::Horizontal);
VehicleSpeedDisplay->setTickPosition(QSlider::TicksBelow);
VehicleSpeedDisplay->setTickInterval(25);

QObject::connect(VehicleSpeedDisplay, SIGNAL(valueChanged(int)), VehicleData, SLOT(VehicleSpeed(int)))

The slot implementationand the logs were already pasted in the first post.

If I am commented the message display box , only
"VehicleSpeed is : 5 " log will be generated, means the slot is getting called only once. But with the exec() call slot is getting called multiple times

Thanks,
Jinu