Cleanup: unify idiosyncratic singletons

The way we handle singletons in QML, QML insists on allocating the
objects. This leads to a very idiosyncratic way of handling
singletons: The global instance pointer is set in the constructor.

Unify all these by implementing a "SillySingleton" template. All
of the weird singleton-classes can derive from this template and
don't have to bother with reimplementing the instance() function
with all the safety-checks, etc.

This serves firstly as documentation but also improves debugging
as we will now see wanted and unwanted creation and destruction
of these weird singletons.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

1 files changed, 2 insertions, 6 deletions

diff --git a/mobile-widgets/qmlprefs.h b/mobile-widgets/qmlprefs.h
index 99819fd7c..70964608b 100644
--- a/mobile-widgets/qmlprefs.h
+++ b/mobile-widgets/qmlprefs.h
@@ -5,9 +5,9 @@
 #include <QObject>
 #include "core/settings/qPrefCloudStorage.h"
 #include "core/settings/qPrefDisplay.h"
+#include "core/singleton.h"
 
-
-class QMLPrefs : public QObject {
+class QMLPrefs : public QObject, public SillySingleton<QMLPrefs> {
 	Q_OBJECT
 	Q_PROPERTY(QString cloudPassword
 				MEMBER m_cloudPassword
@@ -35,9 +35,6 @@ class QMLPrefs : public QObject {
 				NOTIFY oldStatusChanged)
 public:
 	QMLPrefs();
-	~QMLPrefs();
-
-	static QMLPrefs *instance();
 
 	const QString cloudPassword() const;
 	void setCloudPassword(const QString &cloudPassword);
@@ -66,7 +63,6 @@ private:
 	QString m_cloudPin;
 	QString m_cloudUserName;
 	qPrefCloudStorage::cloud_status m_credentialStatus;
-	static QMLPrefs *m_instance;
 	qPrefCloudStorage::cloud_status m_oldStatus;
 	bool m_showPin;