Choice properties which mix types need to have 'allowStr=True' for

command-line processing to work.

fsl/fsleyes/displaycontext/canvasopts.py

@@ -59,7 +59,8 @@ class SliceCanvasOpts(props.HasProperties):
  
 
     zax = props.Choice((0, 1, 2),
-                       alternates=[['x', 'X'], ['y', 'Y'], ['z', 'Z']])
+                       alternates=[['x', 'X'], ['y', 'Y'], ['z', 'Z']],
+                       allowStr=True)
     """The display coordinate system axis to be used as the screen *depth*
     axis.
     """

fsl/fsleyes/displaycontext/sceneopts.py

@@ -61,7 +61,7 @@ class SceneOpts(props.HasProperties):
     #       performance because, for example, the
     #       OrthoEditProfile does numerical comparisons
     #       to it.
-    performance = props.Choice((1, 2, 3, 4), default=4)
+    performance = props.Choice((1, 2, 3, 4), default=4, allowStr=True)
     """User controllable performance setting.
 
     This property is linked to the :attr:`renderMode` and