[PyQt] QSpinBox: behavior on Linux

[TP]

Hi everybody,

I have detected a strange behavior on Linux with QSpinBox (try the code
example below): when the "valueChanged( int )" signal is connected to a 
function that takes some time to execute, sometimes the "up" and "down"
clickable buttons of the QSpinBox increment and decrement its value by 2 or
more, instead of 1. Whereas on Windows it works correctly. Could you try
under Linux and confirm the strange behavior?

I have another question: why does the value of the spinbox change only after
the function has been executed? How to force the spinbox value to change
immediately, and call the function to be executed AFTER?

My version of PyQt: PyQt-x11-gpl-4.4.4
My version of Qt: 4.4.0.

Thanks

##########
from PyQt4.QtCore import *
from PyQt4.QtGui import *
import sys, time

app = QApplication( sys.argv )
dialog = QDialog( )
# dialog.setBackgroundRole( 9 )
dialog.resize( 750, 550 )

def wait_a_moment():
    # pass

    time.sleep( 0.5 )


spinbox = QSpinBox( dialog )

QObject.connect( spinbox
        , SIGNAL( "valueChanged ( int )" )
        , wait_a_moment )

vboxlayout = QVBoxLayout( dialog )
dialog.setLayout( vboxlayout )
dialog.show()

app.exec_()
##########

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