extend instrument tree model

GUI/Models/InstrumentsTreeModel.cpp

@@ -244,20 +244,17 @@ QVariant InstrumentsTreeModel::data(const QModelIndex& index, int role) const
     if (role == Qt::TextAlignmentRole)
         return QVariant(Qt::AlignLeft | Qt::AlignTop);
 
-    if (role == Qt::DecorationRole) {
-        if (item->is<GISASInstrumentItem>())
+    if (role == Qt::DecorationRole)
+        switch (instrumentType(item)) {
+        case Gisas:
             return QIcon(":/images/gisas_instrument.svg");
-
-        if (item->is<OffSpecularInstrumentItem>())
+        case OffSpecular:
             return QIcon(":/images/offspec_instrument.svg");
-
-        if (item->is<SpecularInstrumentItem>())
+        case Specular:
             return QIcon(":/images/specular_instrument.svg");
-
-        if (item->is<DepthProbeInstrumentItem>())
+        case DepthProbe:
             return QIcon(":/images/depth_instrument.svg");
-    }
-
+        }
 
     return QVariant();
 }
@@ -317,3 +314,21 @@ bool InstrumentsTreeModel::isHeadline(const QModelIndex& index) const
 
     return index.internalPointer() == nullptr;
 }
+
+InstrumentsTreeModel::InstrumentType InstrumentsTreeModel::instrumentType(InstrumentItem* item)
+{
+    if (item->is<GISASInstrumentItem>())
+        return Gisas;
+
+    if (item->is<OffSpecularInstrumentItem>())
+        return OffSpecular;
+
+    if (item->is<SpecularInstrumentItem>())
+        return Specular;
+
+    if (item->is<DepthProbeInstrumentItem>())
+        return DepthProbe;
+
+    ASSERT(FALSE);
+    return None;
+}

GUI/Models/InstrumentsTreeModel.h

@@ -59,6 +59,8 @@ public:
     QModelIndex indexOfHeadline(InstrumentType type) const;
     bool isHeadline(const QModelIndex& index) const;
 
+    static InstrumentType instrumentType(InstrumentItem* item);
+
 private:
     void clear();
     QList<InstrumentType> visibleTypes() const;