QTableWidget does not allow updation of a cell

I am using a QTableWidget and setting a delegate to it. The delegate puts a line edit in the first column of any row. The issue is that the SetEditorMethod() of the delegate class is not invoked when the value of the cell(0,0) is updated in the table widget. However it gets invoked for other cells updation. And the result of that is that the data in editor is displayed as per the new value but when I do TableWidget->item(0,0)->text() I receive the old value.