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QDBusPendingCallWatcher Class Reference
^{^{[QtDBus module]}}

The QDBusPendingCallWatcher class provides a convenient way for waiting for asynchronous replies More...

Inherits QObject and QDBusPendingCall.

Methods

__init__ (self, QDBusPendingCall call, QObject parent = None)
bool isFinished (self)
waitForFinished (self)

Qt Signals

void finished (QDBusPendingCallWatcher *)

Detailed Description

The QDBusPendingCallWatcher class provides a convenient way for waiting for asynchronous replies

The QDBusPendingCallWatcher provides the finished() signal that will be emitted when a reply arrives.

It is usually used like the following example:

     QDBusPendingCall async = iface->asyncCall("RemoteMethod", value1, value2);
     QDBusPendingCallWatcher *watcher = new QDBusPendingCallWatcher(async, this);

     QObject.connect(watcher, SIGNAL(finished(QDBusPendingCallWatcher*)),
                      this, SLOT(callFinishedSlot(QDBusPendingCallWatcher*)));

Note that it is not necessary to keep the original QDBusPendingCall object around since QDBusPendingCallWatcher inherits from that class too.

The slot connected to by the above code could be something similar to the following:

 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();
 }

Note the use of QDBusPendingReply to validate the argument types in the reply. If the reply did not contain exactly two arguments (one string and one QByteArray), QDBusPendingReply.isError() will return true.

Method Documentation

QDBusPendingCallWatcher.init (self, QDBusPendingCall call, QObject parent = None)

The parent argument, if not None, causes self to be owned by Qt instead of PyQt.

Creates a QDBusPendingCallWatcher object to watch for replies on the asynchronous pending call call and sets this object's parent to parent.

bool QDBusPendingCallWatcher.isFinished (self)

Returns true if the pending call has finished processing and the reply has been received.

Note that this function only changes state if you call waitForFinished() or if an external D-Bus event happens, which in general only happens if you return to the event loop execution.

See also QDBusPendingReply.isFinished().