[PyQt] How to process QDBusPendingCallWatcher results?

[Evade Flow]

> Try this...
>
>     def callFinishedSlot(self, call):
>         reply = QtDBus.QPyDBusPendingReply(call)

Thanks, Phil. It doesn't work for me yet, I'm getting:

>>> call
<PyQt4.QtDBus.QDBusPendingCallWatcher object at 0x9e9538c>
>>> reply = QtDBus.QPyDBusPendingReply(call)
Traceback (most recent call last):
  File "<string>", line 1, in <fragment>
builtins.AttributeError: 'module' object has no attribute 'QPyDBusPendingReply'

I'm now looking through the build setup to see whether there's some
config setting I missed that is keeping the qpy stuff from getting
built. Any suggestions? (I built from the PyQt4.9.4 release tarball; do
I need to use a development snapshot instead?)


On Mon, Aug 13, 2012 at 4:43 AM, Phil Thompson
<phil at riverbankcomputing.com> wrote:
> On Sun, 12 Aug 2012 23:31:54 -0400, Evade Flow <evadeflow at gmail.com>
> wrote:
>> I'm working on an app that needs to invoke methods in
>> various D-Bus services asynchronously, so I wrote this small program to
>> test the basic machinery:
>>
>>
>>    from PyQt4 import QtCore, QtDBus
>>
>>    class DeviceInterface(QtDBus.QDBusAbstractInterface):
>>
>>        def __init__(self, service, path, connection, parent=None):
>>            super().__init__(service, path,
>>                             'org.freedesktop.UDisks.Device',
>>                             connection, parent)
>>
>>        @QtCore.pyqtSlot(QtDBus.QDBusArgument)
>>        def callFinishedSlot(self, arg):
>>            print("Got result:", arg)
>>
>>
>>    if __name__ == '__main__':
>>        import sys
>>        app = QtCore.QCoreApplication(sys.argv)
>>
>>        dev = DeviceInterface('org.freedesktop.UDisks.Device',
>>                              '/org/freedesktop/UDisks/Device/sda1',
>>                              QtDBus.QDBusConnection.systemBus(), app)
>>
>>        async = dev.asyncCall("FilesystemListOpenFiles");
>>        watcher = QtDBus.QDBusPendingCallWatcher(async, dev)
>>        watcher.finished.connect(dev.callFinishedSlot)
>>        sys.exit(app.exec_())
>>
>>
>> It seems to work(?) Anyway, it prints:
>>
>>    Got result: <PyQt4.QtDBus.QDBusPendingCallWatcher object at
> 0xb740c77c>
>>
>> The trouble is, I can't figure out how to get results out of the
>> QDBusPendingCallWatcher object.  The C++ code I adapted the above
>> example from does this:
>>
>>     void MyClass.callFinishedSlot(QDBusPendingCallWatcher *call)
>>     {
>>         QDBusPendingReply<QString, QByteArray> reply = *call;
>>         if (reply.isError()) {
>>             showError();
>>         } else {
>>             QString text = reply.argumentAt<0>();
>>             QByteArray data = reply.argumentAt<1>();
>>             showReply(text, data);
>>         }
>>         call->deleteLater();
>>     }
>>
>> Can anyone suggest how I might convert the C++ slot syntax to something
>> that will work with PyQt?  Thanks!
>
> Try this...
>
>     def callFinishedSlot(self, call):
>         reply = QtDBus.QPyDBusPendingReply(call)
>
>         if reply.isError():
>             self.showError()
>         else:
>             text = reply.argumentAt(0)
>             data = reply.argumentAt(1)
>
> ...etc.
>
> Phil