Created by: yxqd
In https://github.com/ornlneutronimaging/iMars3D/blob/a7d9e7279bfc8090c7ea9c6c3b92393d16391a66/python/imars3d/jnbui/fileselector.py and https://github.com/ornlneutronimaging/iMars3D/blob/a7d9e7279bfc8090c7ea9c6c3b92393d16391a66/python/imars3d/jnbui/imageslider.py