[PyQt] PyQt4 problem: QApplication() has an invalid type

Ala Al-Shaibani ala.alshaibani at gmail.com
Wed Jun 17 13:38:42 BST 2009

Hello everyone.

I am using Python 2.5.1 (default python for OS X) on macintosh.

I installed few libraries, including the scipy library (scipy, numpy,
matplotlib and ipython).

I then installed Qt, SIP and PyQt (latest versions of each).

My problem is with this code:

import sys
from PyQt4 import QtGui
app = QtGui.QApplication(sys.argv)

For which I receive the error: TypeError: argument 1 of
PyQt4.QtGui.QApplication() has an invalid type

Here are few tests that I did:

print sys.argv: test.py
type(sys.argv): <type 'list'>

Also, replacing ..... app = QtGui.QApplication(sys.argv)..... with
.....app = QtGui.QApplication([]).... results with the same error.

Would appreciate any help, thanks.

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