numberOfThreads has to be unsigned

GUI/Model/Session/SimulationOptionsItem.cpp

@@ -74,12 +74,12 @@ SimulationOptionsItem::SimulationOptionsItem() : SessionItem(M_TYPE)
         });
 }
 
-int SimulationOptionsItem::numberOfThreads() const
+unsigned SimulationOptionsItem::numberOfThreads() const
 {
-    return getItemValue(P_NTHREADS).toInt();
+    return getItemValue(P_NTHREADS).toUInt();
 }
 
-void SimulationOptionsItem::setNumberOfThreads(int number)
+void SimulationOptionsItem::setNumberOfThreads(unsigned number)
 {
     setItemValue(P_NTHREADS, number);
 }

GUI/Model/Session/SimulationOptionsItem.h

@@ -36,8 +36,8 @@ public:
 
     explicit SimulationOptionsItem();
 
-    void setNumberOfThreads(int n);
-    int numberOfThreads() const;
+    void setNumberOfThreads(unsigned n);
+    unsigned numberOfThreads() const;
 
     void setRunImmediately(bool runImmediately);
     bool runImmediately() const;