PyQT3.3 problem

Jim jimb417 at NO*
Thu Aug 1 05:43:57 CEST 2002

I'm having trouble with this code which displays two pushbuttons and one 
label. I want to change the text in the label when one of the buttons is 

from qt import *
import sys

class Widget(QWidget):

                def __init__(self, parent = None, name = None):
                        QWidget.__init__(self, parent, name)

                        hello = QPushButton( "Hello There!", self )
                        hello.setGeometry(80, 80, 100, 120)

                        button = QPushButton( "Text", self )
                        button.setGeometry( 200, 200, 40, 40 )

                        label = QLabel( "This is some text", self )
                        label.setGeometry( 80, 220, 100, 20 )

                        self.connect( hello, SIGNAL( "clicked()" ), qApp, SLOT( "quit()" ) )
                        self.connect( button, SIGNAL( "clicked()" ),  qApp, 

                def buttonClicked( self ):
                        label.setText ( "Set" )

app = QApplication (sys.argv)
a = Widget()
a.setGeometry( 100, 100, 300, 300 )
a.setCaption( "This is a widget")
app.setMainWidget( a )

What is the proper way to implement the custom slot correctly?  I wrote 
this from scratch ( not using Qt Designer ) When I run this code, this 
error pops up:

File "", line 27 in ?
a = Widget()
File "", line 19 in __init__
self.connect( button, SIGNAL( "clicked()" ), qApp, self.buttonClicked() )
File "", line 22 in buttonClicked
label.setText( "Changed" )
NameError: global name 'label' not defined
Mutex destroy failure: Device or resource busy

How can 'label' be global when it is a member of the class Widget? The docs 
aren't very clear on this. Can anyone out there give me a nudge in the right
direction on getting this to work. If you comment out line 19, the widget 
will display onscreen( of course the button labled "Text" will do nothing 
when clicked, the other button closes the program ) Thanks for reading this 
and for any assistance.


Registered Linux User #269187

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