PyQt: How to get QTableWidgetItem contents while item is being edited? - pyqt4

Question

In the end, the problem I'm trying to solve is that of someone editing a field in a QTableWidget and then clicking "OK" before hitting the enter key or changing focus out of the table cell.
Default behavior seems to be to ignore this cell, as it hasn't "committed".
Here's a quick example:
#!/usr/bin/env python
import sys
import pprint
from PyQt4 import QtCore,QtGui
class Dialog(QtGui.QDialog):
def __init__(self,parent=None):
super(Dialog,self).__init__(parent)
self.table = QtGui.QTableWidget(5,2)
button_box = QtGui.QDialogButtonBox(QtGui.QDialogButtonBox.Ok|QtGui.QDialogButtonBox.Cancel)
button_box.accepted.connect(self.accept)
button_box.rejected.connect(self.reject)
layout = QtGui.QVBoxLayout()
layout.addWidget(self.table)
layout.addWidget(button_box)
self.setLayout(layout)
def accept(self):
ret = {}
for i in range(self.table.rowCount()):
k = self.table.item(i,0)
v = self.table.item(i,1)
if not k:
continue
if k.text().isEmpty():
continue
if not v:
v = QtGui.QTableWidgetItem("")
ret[str(k.text())] = str(v.text())
pprint.pprint(ret)
def main():
app = QtGui.QApplication(sys.argv)
main = Dialog()
main.show()
sys.exit(app.exec_())
if __name__ == "__main__":
main()
In this example, if I enter a in the first cell then b in the second cell; then click "OK" without first hitting the enter key or changing focus, I will see printed:
{'a': ''}
When I want to see:
{'a': 'b'}
An idea I had was to treat the cell like a QLineEdit and use textChanged to see when the user was typing, and then, behind the scenes, setItem of the cell with each key stroke -- the idea being that the data in the cell is always up to date. I attempted this by using QStyledItemDelegate (below) so that it edits like a QLineEdit (which has a textChanged signal). This works to some degree, as I can print out the changes from the delegate itself, but I can't seem to get the textChanged signal anywhere it's useful (in other words, the dialog doesn't see this, therefore it can't setItem in the table).
class LineEditDelegate(QtGui.QStyledItemDelegate):
textChanged = QtCore.pyqtSignal(str)
def createEditor(self, parent, option, index):
editor = QtGui.QLineEdit(parent)
editor.textChanged.connect(self.textChanged)
return editor
But that's not doing the trick.
I also tried emitting a commitData signal when the QLineEdit's textChanged fires, but that also has not helped.
Is there a way to get cell contents while the cell is still being edited?