texture doesn't show in jupyter notebook

i use the following code in jupyter notebook:
from tvtk.api import tvtk
from mayavi import mlab
import numpy as np

mlab.init_notebook()
mlab.clf()
fig=mlab.figure(size=(800,640),bgcolor=(0.16,0.28,0.46))
X,Y=np.mgrid[-1:1:20j,-1:1:20j]
Z = -np.cos(Y*X)+.5

img_filename='demo.jpg'
img=tvtk.JPEGReader(file_name=img_filename)
texture=tvtk.Texture(input_connection=img.output_port, interpolate=1)

s = mlab.surf(X,Y,Z,color=(1.,1.,1.))
s.actor.actor.mapper.scalar_visibility=False
s.actor.enable_texture=True
s.actor.tcoord_generator_mode='plane'
s.actor.actor.texture=texture

from mayavi.sources.api import BuiltinSurface
p = mlab.pipeline.surface( BuiltinSurface(source='plane') )
p.actor.actor.mapper.scalar_visibility=False
p.actor.enable_texture=True
p.actor.tcoord_generator_mode='plane'
p.actor.actor.texture=texture
mlab.show()
fig

and i get this:
is this a bug?or i should add something to fix this?