Grégory Starck wrote: > Hi dear list, > > on windows7-64, with python32 (and also with python27) (-x86) and > pyqt-4.8.5-1: > > First of all: I'm quite new with Qt (pyqt).. and so I don't know all > of it, even more specifically about the restrictions/exceptions/etc.., > from far. > > in a quite simple window (just a tableWidget and few buttons > basically) : > > I connected the itemChanged signal/event of the tableWidget to one of > my method. ( gui.tableWidget.itemChanged.connect(self.onCellChanged) > ) > > but in this method I want to be able to eventually re-modify the value > of the item (depending on some conditions).. > > but doing so re-generate a itemChanged event.. so in that case my > method was called 1 extra time that I don't want. > > I used to work around that by : on begin of my method : I disconnect > the event itemChanged from my method. And on exit of my method I > re-connect the signal to it. > > my question is : does it sound like all right to you ?? > > because with that I sometimes (but quite highly reproducible) get real > crash from QtCore.. but without any valuable detail. as far as I > understood : it could be a problem because I disconnect-reconnect the > event handler from within the handler itself AND ALSO, apparently, > that I was also displaying a QtGui.QMessageBox from within my method. > (when I remove the display of the Qmsgbox then the crash doesn't occur > anymore, never, as far I could see). > > Now I've totally work around the problem/crash by using a bool flag > that I initially set to False. when my itemChanged event handler > enters : it checks for the flag. if True -> the method directly > returns. Else it sets the flag to True and the method executes > normally. before returning from it I reset the flag to False. So that > if I change the value of the item in the method then the method will > still be called 1 extra time but I notice it thx to the flag.
A cleaner way to do this is to use widget.blockSignals(True) before re-modifying the value and then widget.blockSignals(False) afterward. -Doug _______________________________________________ PyQt mailing list PyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
