worked on thread safety with tasks

app/common/threadedobject.h

@@ -0,0 +1,25 @@
+#ifndef THREADEDOBJECT_H
+#define THREADEDOBJECT_H
+
+#include <QMutex>
+
+class ThreadedObject
+{
+public:
+  ThreadedObject();
+
+  void LockMutex();
+  void UnlockMutex();
+  bool TryLockMutex(int timeout = 0);
+
+  void LockDeletes();
+  void UnlockDeletes();
+  bool AreDeletesLocked();
+
+private:
+  QMutex threadobj_main_lock_;
+
+  QAtomicInt threadobj_delete_lock_;
+};
+
+#endif // THREADEDOBJECT_H