Add KConfigGui::setSessionConfig()

When the application receives a saveState signal it needs to replace the
current KConfig object with a new one based on the QSessionManager
information. Add a new interface that accepts the new session id and key.

BUG: 346768
REVIEW: 123705

src/gui/kconfiggui.cpp

@@ -25,28 +25,51 @@
 
 #include <kconfig.h>
 
+static QString configName(const QString &id, const QString &key)
+{
+    return(QLatin1String("session/") + QGuiApplication::applicationName() +
+           QLatin1Char('_')          + id                                 +
+           QLatin1Char('_')          + key);
+}
+
 static KConfig *s_sessionConfig = Q_NULLPTR;
 
 KConfig *KConfigGui::sessionConfig()
 {
-    if (!s_sessionConfig) { // create an instance specific config object
-        s_sessionConfig = new KConfig(sessionConfigName(), KConfig::SimpleConfig);
+#ifdef QT_NO_SESSIONMANAGER
+#error QT_NO_SESSIONMANAGER was set, this will not compile. Reconfigure Qt with Session management support.
+#endif
+    if (!hasSessionConfig()) {
+        // create the default instance specific config object
+        // from applications' -session command line parameter
+        s_sessionConfig = new KConfig(configName(qApp->sessionId(),
+                                                 qApp->sessionKey()),
+                                      KConfig::SimpleConfig);
     }
+
     return s_sessionConfig;
 }
 
+void KConfigGui::setSessionConfig(const QString &id, const QString &key)
+{
+    if (hasSessionConfig()) {
+        delete s_sessionConfig;
+        s_sessionConfig = Q_NULLPTR;
+    }
+
+    // create a new instance specific config object from supplied id & key
+    s_sessionConfig = new KConfig(configName(id, key),
+                                  KConfig::SimpleConfig);
+}
+
 bool KConfigGui::hasSessionConfig()
 {
     return s_sessionConfig != Q_NULLPTR;
 }
 
+#ifndef KDE_NO_DEPRECATED
 QString KConfigGui::sessionConfigName()
 {
-#ifdef QT_NO_SESSIONMANAGER
-#error QT_NO_SESSIONMANAGER was set, this will not compile. Reconfigure Qt with Session management support.
-#endif
-    const QString sessionKey = qApp->sessionKey();
-    const QString sessionId = qApp->sessionId();
-    return QString(QLatin1String("session/%1_%2_%3")).arg(QGuiApplication::applicationName()).arg(sessionId).arg(sessionKey);
+    return sessionConfig()->name();
 }
-
+#endif

src/gui/kconfiggui.h

@@ -31,7 +31,7 @@ class KConfig;
 namespace KConfigGui
 {
 /**
- * Returns the application session config object.
+ * Returns the current application session config object.
  *
  * @return A pointer to the application's instance specific
  * KConfig object.
@@ -39,6 +39,16 @@ namespace KConfigGui
  */
 KCONFIGGUI_EXPORT KConfig *sessionConfig();
 
+/**
+ * Replaces the current application session config object.
+ *
+ * @param id  new session id
+ * @param key new session key
+ *
+ * @since 5.11
+ */
+KCONFIGGUI_EXPORT void setSessionConfig(const QString &id, const QString &key);
+
 /**
  * Indicates if a session config has been created for that application
  * (ie. if sessionConfig() got called at least once)
@@ -51,8 +61,11 @@ KCONFIGGUI_EXPORT bool hasSessionConfig();
  * Returns the name of the application session
  *
  * @return the application session name
+ * @deprecated since 5.11, use sessionConfig()->name()
  */
-KCONFIGGUI_EXPORT QString sessionConfigName();
+#ifndef KDE_NO_DEPRECATED
+KCONFIGGUI_DEPRECATED QString sessionConfigName();
+#endif
 }
 
 #endif // KCONFIGGUI_H