self.sender() always None

elveatles

I'm using PySide. I have a QTableWidget with QComboBoxes inside, which was done by using setCellWidget. I connect each combo box's currentIndexChanged signal to a slot. When I try to get the combo box that sent the signal using self.sender(), it's always None. Does anyone else have this problem?

SGaist

Hi,

Can you show a minimal sample code that exhibit this behavior ?

elveatles

What's weird is I tried the same code again today, but I'm getting the sender this time. Something is not right with how PySide passes the sender, but I can tell this is one of those bugs that will be really hard to track down since it's really inconsistent. Here's a simplified version of what I'm working with:

import sys

from PySide.QtCore import *
from PySide.QtGui import *

class CustomDialog(QDialog):
    def __init__(self, parent=None):
        super(CustomDialog, self).__init__(parent)

        self.setLayout(QVBoxLayout())

        self.table = QTableWidget()
        self.table.setColumnCount(2)
        self.layout().addWidget(self.table)

        self.table.setRowCount(10)
        for row in xrange(self.table.rowCount()):
            item = QTableWidgetItem(str(row))
            self.table.setItem(row, 0, item)

            combo = QComboBox()
            combo.addItems(['one', 'two', 'three'])
            combo.currentIndexChanged.connect(self.onIndexChanged)
            self.table.setCellWidget(row, 1, combo)

    @Slot(int)
    def onIndexChanged(self, index):
        print self.sender()

def main():
    app = QApplication(sys.argv)
    dialog = CustomDialog()
    dialog.show()
    app.exec_()

if __name__ == '__main__':
    main()

If you don't get the bug, I wouldn't spend too much time looking into it, but I appreciate the help.