ClientExtension: Add onRegister()/onUnregister() functions

CMakeLists.txt

@@ -5,7 +5,7 @@
 cmake_minimum_required(VERSION 3.7)
 project(qxmpp VERSION 1.7.0)
 
-set(SO_VERSION 4)
+set(SO_VERSION 5)
 
 # C++ standard settings:
 set(CMAKE_CXX_STANDARD 17)

src/client/QXmppClient.cpp

@@ -298,20 +298,20 @@ bool QXmppClient::insertExtension(int index, QXmppClientExtension *extension)
     }
 
     extension->setParent(this);
-    extension->setClient(this);
     d->extensions.insert(index, extension);
+    extension->setClient(this);
     return true;
 }
 
+///
 /// Unregisters the given extension from the client. If the extension
 /// is found, it will be destroyed.
 ///
-/// \param extension
-
 bool QXmppClient::removeExtension(QXmppClientExtension *extension)
 {
     if (d->extensions.contains(extension)) {
         d->extensions.removeAll(extension);
+        extension->setClient(nullptr);
         delete extension;
         return true;
     } else {

src/client/QXmppClientExtension.cpp

@@ -87,7 +87,35 @@ QXmppClient *QXmppClientExtension::client()
 ///
 void QXmppClientExtension::setClient(QXmppClient *client)
 {
+    if (m_client != nullptr) {
+        onUnregistered(m_client);
+    }
+
     m_client = client;
+
+    if (client != nullptr) {
+        onRegistered(client);
+    }
+}
+
+///
+/// Called after the extension has been added to a QXmppClient.
+///
+/// \param client
+///
+void QXmppClientExtension::onRegistered(QXmppClient *client)
+{
+    Q_UNUSED(client);
+}
+
+///
+/// Called after the extension has been removed from a QXmppClient.
+///
+/// \param client
+///
+void QXmppClientExtension::onUnregistered(QXmppClient *client)
+{
+    Q_UNUSED(client);
 }
 
 ///

src/client/QXmppClientExtension.h

@@ -47,6 +47,9 @@ class QXMPP_EXPORT QXmppClientExtension : public QXmppLoggable, public QXmppExte
     QXmppClient *client();
     virtual void setClient(QXmppClient *client);
 
+    virtual void onRegistered(QXmppClient *client);
+    virtual void onUnregistered(QXmppClient *client);
+
     void injectIq(const QDomElement &element, const std::optional<QXmppE2eeMetadata> &e2eeMetadata);
     bool injectMessage(QXmppMessage &&message);