QtCore.QObject.connect in a loop only affects the last instance

by

Put the loop variable in a default argument, like this:

lambda state, instance=instance: findInstance.projectsInstance.myslot(
    "TWCH", findInstance, instance.text(), instance.checkState(), instance)

This will give each lambda its own local copy of the instance variable.

EDIT

Here’s a simple script that demonstrates how to use default lambda arguments:

from PyQt4 import QtGui

class Window(QtGui.QWidget):
    def __init__(self):
        QtGui.QWidget.__init__(self)
        layout = QtGui.QVBoxLayout(self)
        for index in range(4):
            instance = QtGui.QCheckBox('Checkbox(%d)' % index, self)
            instance.stateChanged.connect(
                lambda state, instance=instance:
                    self.mySlot(instance.text()))
            layout.addWidget(instance)

    def mySlot(self, text):
        print('clicked: %s' % text)


if __name__ == '__main__':

    import sys
    app = QtGui.QApplication(sys.argv)
    window = Window()
    window.show()
    sys.exit(app.exec_())

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