diff --git a/src/Mod/Assembly/Gui/ViewProviderConstraintAlignment.h b/src/Mod/Assembly/Gui/ViewProviderConstraintAlignment.h
index 38d2fadde9..459206fd54 100644
--- a/src/Mod/Assembly/Gui/ViewProviderConstraintAlignment.h
+++ b/src/Mod/Assembly/Gui/ViewProviderConstraintAlignment.h
@@ -34,6 +34,9 @@ class AssemblyGuiExport ViewProviderConstraintAlignment : public Gui::ViewProvid
 
 public:
     ViewProviderConstraintAlignment();
+    
+    /// checks whether the view provider is visible or not in tree
+    virtual bool isShow(void) const {return true;};
 
 };
 
diff --git a/src/Mod/Assembly/Gui/ViewProviderConstraintAngle.h b/src/Mod/Assembly/Gui/ViewProviderConstraintAngle.h
index cd68cbe8c4..ed1097f4d1 100644
--- a/src/Mod/Assembly/Gui/ViewProviderConstraintAngle.h
+++ b/src/Mod/Assembly/Gui/ViewProviderConstraintAngle.h
@@ -35,6 +35,8 @@ class AssemblyGuiExport ViewProviderConstraintAngle : public Gui::ViewProviderDo
 public:
     ViewProviderConstraintAngle();
 
+    /// checks whether the view provider is visible or not in tree
+    virtual bool isShow(void) const {return true;};
 };
 
 };
diff --git a/src/Mod/Assembly/Gui/ViewProviderConstraintCoincidence.h b/src/Mod/Assembly/Gui/ViewProviderConstraintCoincidence.h
index a4cbacd734..dee6ab0a25 100644
--- a/src/Mod/Assembly/Gui/ViewProviderConstraintCoincidence.h
+++ b/src/Mod/Assembly/Gui/ViewProviderConstraintCoincidence.h
@@ -35,6 +35,8 @@ class AssemblyGuiExport ViewProviderConstraintCoincidence : public Gui::ViewProv
 public:
     ViewProviderConstraintCoincidence();
 
+    /// checks whether the view provider is visible or not in tree
+    virtual bool isShow(void) const {return true;};
 };
 
 };
diff --git a/src/Mod/Assembly/Gui/ViewProviderConstraintDistance.h b/src/Mod/Assembly/Gui/ViewProviderConstraintDistance.h
index 1c1c1c3644..9fbff5ba2a 100644
--- a/src/Mod/Assembly/Gui/ViewProviderConstraintDistance.h
+++ b/src/Mod/Assembly/Gui/ViewProviderConstraintDistance.h
@@ -35,6 +35,8 @@ class AssemblyGuiExport ViewProviderConstraintDistance : public Gui::ViewProvide
 public:
     ViewProviderConstraintDistance();
 
+    /// checks whether the view provider is visible or not in tree
+    virtual bool isShow(void) const {return true;};
 };
 
 };
diff --git a/src/Mod/Assembly/Gui/ViewProviderConstraintFix.h b/src/Mod/Assembly/Gui/ViewProviderConstraintFix.h
index d4fabcc0c2..66a1e158e8 100644
--- a/src/Mod/Assembly/Gui/ViewProviderConstraintFix.h
+++ b/src/Mod/Assembly/Gui/ViewProviderConstraintFix.h
@@ -35,6 +35,8 @@ class AssemblyGuiExport ViewProviderConstraintFix : public Gui::ViewProviderDocu
 public:
     ViewProviderConstraintFix();
 
+    /// checks whether the view provider is visible or not in tree
+    virtual bool isShow(void) const {return true;};
 };
 
 };
diff --git a/src/Mod/Assembly/Gui/ViewProviderConstraintGroup.cpp b/src/Mod/Assembly/Gui/ViewProviderConstraintGroup.cpp
index a03662c2dd..b8a7c2d4a8 100644
--- a/src/Mod/Assembly/Gui/ViewProviderConstraintGroup.cpp
+++ b/src/Mod/Assembly/Gui/ViewProviderConstraintGroup.cpp
@@ -57,7 +57,7 @@ void ViewProviderConstraintGroup::attach(App::DocumentObject *pcFeat)
 
 
     // putting all together with the switch
-//    addDisplayMaskMode(getChildRoot(), "Main");
+    //addDisplayMaskMode(getChildRoot(), "Main");
 }
 
 void ViewProviderConstraintGroup::setDisplayMode(const char* ModeName)
diff --git a/src/Mod/Assembly/Gui/ViewProviderConstraintGroup.h b/src/Mod/Assembly/Gui/ViewProviderConstraintGroup.h
index dabcb2af95..2adb572ffb 100644
--- a/src/Mod/Assembly/Gui/ViewProviderConstraintGroup.h
+++ b/src/Mod/Assembly/Gui/ViewProviderConstraintGroup.h
@@ -46,8 +46,10 @@ public:
     virtual std::vector<std::string> getDisplayModes(void) const;
 
     virtual std::vector<App::DocumentObject*> claimChildren(void)const;
-
     virtual std::vector<App::DocumentObject*> claimChildren3D(void)const;
+    
+    /// checks whether the view provider is visible or not in tree
+    virtual bool isShow(void) const {return true;};
 
 };
 
diff --git a/src/Mod/Assembly/Gui/ViewProviderConstraintOrientation.h b/src/Mod/Assembly/Gui/ViewProviderConstraintOrientation.h
index 1109d5d89b..4276a46df6 100644
--- a/src/Mod/Assembly/Gui/ViewProviderConstraintOrientation.h
+++ b/src/Mod/Assembly/Gui/ViewProviderConstraintOrientation.h
@@ -35,6 +35,8 @@ class AssemblyGuiExport ViewProviderConstraintOrientation : public Gui::ViewProv
 public:
     ViewProviderConstraintOrientation();
 
+    /// checks whether the view provider is visible or not in tree
+    virtual bool isShow(void) const {return true;};
 };
 
 };