diff --git a/invesalius/data/styles.py b/invesalius/data/styles.py
index ce020f2..569e268 100644
--- a/invesalius/data/styles.py
+++ b/invesalius/data/styles.py
@@ -96,6 +96,7 @@ class CrossInteractorStyle(DefaultInteractorStyle):
     def __init__(self, viewer):
         DefaultInteractorStyle.__init__(self, viewer)
 
+        self.viewer = viewer
         self.orientation = viewer.orientation
         self.slice_actor = viewer.slice_data.actor
         self.slice_data = viewer.slice_data
@@ -106,6 +107,12 @@ class CrossInteractorStyle(DefaultInteractorStyle):
         self.AddObserver("LeftButtonPressEvent", self.OnCrossMouseClick)
         self.AddObserver("LeftButtonReleaseEvent", self.OnReleaseLeftButton)
 
+    def SetUp(self):
+        self.viewer._set_cross_visibility(1)
+
+    def CleanUp(self):
+        self.viewer._set_cross_visibility(0)
+
     def OnCrossMouseClick(self, obj, evt):
         iren = obj.GetInteractor()
         self.ChangeCrossPosition(iren)
@@ -214,6 +221,14 @@ class WWWLInteractorStyle(DefaultInteractorStyle):
         self.AddObserver("MouseMoveEvent", self.OnWindowLevelMove)
         self.AddObserver("LeftButtonPressEvent", self.OnWindowLevelClick)
 
+    def SetUp(self):
+        self.viewer.on_wl = True
+        self.viewer.wl_text.Show()
+
+    def CleanUp(self):
+        self.viewer.on_wl = False
+        self.viewer.wl_text.Hide()
+
     def OnWindowLevelMove(self, obj, evt):
         if (self.left_pressed):
             iren = obj.GetInteractor()
@@ -584,3 +599,20 @@ class EditorInteractorStyle(DefaultInteractorStyle):
         elif bounds[4] == bounds[5]:
             z = bounds[4]
         return x, y, z
+
+
+def get_style(style):
+    STYLES = {
+              const.STATE_DEFAULT: DefaultInteractorStyle,
+              const.SLICE_STATE_CROSS: CrossInteractorStyle,
+              const.STATE_WL: WWWLInteractorStyle,
+              const.STATE_MEASURE_DISTANCE: LinearMeasureInteractorStyle,
+              const.STATE_MEASURE_ANGLE: AngularMeasureInteractorStyle,
+              const.STATE_PAN: PanMoveInteractorStyle,
+              const.STATE_SPIN: SpinInteractorStyle,
+              const.STATE_ZOOM: ZoomInteractorStyle,
+              const.STATE_ZOOM_SL: ZoomSLInteractorStyle,
+              const.SLICE_STATE_SCROLL: ChangeSliceInteractorStyle,
+              const.SLICE_STATE_EDITOR: EditorInteractorStyle,
+             }
+    return STYLES[style]
diff --git a/invesalius/data/viewer_slice.py b/invesalius/data/viewer_slice.py
index 76d8b0f..35a1995 100755
--- a/invesalius/data/viewer_slice.py
+++ b/invesalius/data/viewer_slice.py
@@ -67,6 +67,7 @@ class Viewer(wx.Panel):
         self.spined_image = False #Use to control to spin
         self.paned_image = False
         
+        self.style = None
         self.last_position_mouse_move = ()
         self.state = const.STATE_DEFAULT
 
@@ -175,89 +176,21 @@ class Viewer(wx.Panel):
         interactor.SetInteractorStyle(style)
 
     def SetInteractorStyle(self, state):
-        self.__set_cross_visibility(0)
-        self.on_wl = False
-        self.wl_text.Hide()
-        self.state = state
-
-        if state == const.STATE_DEFAULT:
-            style = styles.DefaultInteractorStyle(self)
-            self.style = style
-            self.interactor.SetInteractorStyle(style)
-            self.interactor.Render()
-
-        elif state == const.SLICE_STATE_CROSS:
-            style = styles.CrossInteractorStyle(self)
-            self.style = style
-            self.interactor.SetInteractorStyle(style)
-
-            self.__set_cross_visibility(1)
-            Publisher.sendMessage('Activate ball reference')
-
-            self.interactor.Render()
-
-        elif state == const.STATE_WL:
-            self.on_wl = True
-            self.wl_text.Show()
-
-            style = styles.WWWLInteractorStyle(self)
-            self.style = style
-            self.interactor.SetInteractorStyle(style)
-            self.interactor.Render()
-
-        elif state == const.STATE_MEASURE_DISTANCE:
-            style = styles.LinearMeasureInteractorStyle(self)
-            self.style = style
-            self.interactor.SetInteractorStyle(style)
-            self.interactor.Render()
-
-        elif state == const.STATE_MEASURE_ANGLE:
-            style = styles.AngularMeasureInteractorStyle(self)
-            self.style = style
-            self.interactor.SetInteractorStyle(style)
-            self.interactor.Render()
+        cleanup = getattr(self.style, 'CleanUp', None)
+        if cleanup:
+            self.style.CleanUp()
 
-        elif state == const.STATE_PAN:
-            style = styles.PanMoveInteractorStyle(self)
+        style = styles.get_style(state)(self)
 
-            self.style = style
-            self.interactor.SetInteractorStyle(style)
-            self.interactor.Render()
+        setup = getattr(style, 'SetUp', None)
+        if setup:
+            style.SetUp()
 
-        elif state == const.STATE_SPIN:
-            style = styles.SpinInteractorStyle(self)
-
-            self.style = style
-            self.interactor.SetInteractorStyle(style)
-            self.interactor.Render()
-
-        elif state == const.STATE_ZOOM:
-            style = styles.ZoomInteractorStyle(self)
-
-            self.style = style
-            self.interactor.SetInteractorStyle(style)
-            self.interactor.Render()
-
-        elif state == const.STATE_ZOOM_SL:
-            style = styles.ZoomSLInteractorStyle(self)
-
-            self.style = style
-            self.interactor.SetInteractorStyle(style)
-            self.interactor.Render()
-
-        elif state == const.SLICE_STATE_SCROLL:
-            style = styles.ChangeSliceInteractorStyle(self)
-
-            self.style = style
-            self.interactor.SetInteractorStyle(style)
-            self.interactor.Render()
-
-        elif state == const.SLICE_STATE_EDITOR:
-            style = styles.EditorInteractorStyle(self)
+        self.style = style
+        self.interactor.SetInteractorStyle(style)
+        self.interactor.Render()
 
-            self.style = style
-            self.interactor.SetInteractorStyle(style)
-            self.interactor.Render()
+        self.state = state
 
     def UpdateWindowLevelValue(self, pubsub_evt):
         window, level = pubsub_evt.data
@@ -664,7 +597,7 @@ class Viewer(wx.Panel):
         Publisher.subscribe(self.UpdateWindowLevelValue,\
                                  'Update window level value')
 
-        #Publisher.subscribe(self.__set_cross_visibility,\
+        #Publisher.subscribe(self._set_cross_visibility,\
         #                         'Set cross visibility')
         ###
         Publisher.subscribe(self.__set_layout,
@@ -931,7 +864,7 @@ class Viewer(wx.Panel):
         pos = pubsub_evt.data
         self.cross.SetFocalPoint(pos)
 
-    def __set_cross_visibility(self, visibility):
+    def _set_cross_visibility(self, visibility):
         self.cross_actor.SetVisibility(visibility)
 
     def _set_editor_cursor_visibility(self, visibility):
--
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