Comments on: PyKDE4: new style signals and slots

By: gml

gml — Fri, 02 Apr 2010 10:50:14 +0000

Thanks you, I’ll try it. This night I’ve avoid the problem by a work-around : keeping updated a list of email widgets, then when the clicked event is trigged, searching for the email which is set “selected” with the mouse events.

Not really beautiful and efficient, but it works.

I will try your solution this afternoon, it can reduce my code size a little, and it’s much more sexy. Thanks again for your help and your patience !

By: Einar

Einar — Fri, 02 Apr 2010 07:10:20 +0000

I found out the reason: it must be a callable, and instead (my bad, because I didn’t realize it) you call the function inside, which returns None as it’s a signal. So, to fix this you have two options:

1. Use partial from functools:

from functools import partial

uid = 1
wrapped_slot = partial(self.openWindow, uid)
self.message.button.clicked.connect(wrapped_slot)

2. Make a whole slot for it, but in that case you need to put uid in an instance variable or something:

self._uid = 1

self.message.button.clicked.connect(self.open_window)

def open_window(self):

self.openWindow.emit(self._uid)

By: gml

gml — Fri, 02 Apr 2010 00:36:43 +0000

Ok, when I set :

openWindow = QtCore.pyqtSignal(int)

within my class (not the Widget class, the upper one), but outside the __init__, it works.

Then I get another problem :

uid = 1
message.button.clicked.connect(self.openWindow.emit(uid))

(I’ve used message.button, which is a QPushButton, to be sure that the problem doesn’t come from clickable or not)

I get this :

message.button.clicked.connect(self.openWindow.emit(uid))
TypeError: connect() slot argument should be a callable or a signal, not ‘NoneType’

It doesn’t make sense for me :/

By: gml

gml — Thu, 01 Apr 2010 21:05:38 +0000

It doesn’t seem to work, or i’m just too new to Qt to understand…

I use this to make QWidget clickable : http://diotavelli.net/PyQtWiki/Making%20non-clickable%20widgets%20clickable to make my QWidget clickable.

Then, here is my code :

self.openWindow = QtCore.pyqtSignal(int)
self.clickable(message).connect(self.openWindow.emit(11))

And when I try it :
self.clickable(message).connect(self.openWindow.emit(11))
AttributeError: ‘PyQt4.QtCore.pyqtSignal’ object has no attribute ‘emit’

What i’m doing wrong ?

By: gml

gml — Thu, 01 Apr 2010 18:05:03 +0000

Indeed, QWidget doesn’t have clicked(), i’ve implemented it.

I’ll try your solution as soon as i can, thanks you !

By: Einar

Einar — Thu, 01 Apr 2010 16:29:02 +0000

I’m not sure if QWidget has the clicked() signal: if it doesn’t have it, you’ll have to implement it yourself in the appropriate event. As for the rest, you just define a signal in your class

openWindow = QtCore.pyqtSignal(int)

(assuming that you store the ID as an int)

then something like this, in the appropriate place of the code(assuming you have the id in “my_id”):

self.widget.clicked.connect(self.openWindowl.emit(my_id))

By: gml

gml — Thu, 01 Apr 2010 16:21:36 +0000

Hi,

i’m unable to find a way to do a really simple thing in PyQt, maybe you could help me ?

I have a QScrollwidget containing a lot of QWidgets. Each QWidget have a UID attribute. I would like the following thing : when I click on a QWidget, it will emit a signal containing the UID argument.

Actually, each QWidget represents an email, and when I click on an email-widget, I would like to open it in another window, using his UID.

Do you have an idea ?

Regards,
gml