def delete_channel_cb(self, viewer, chinfo):
        """Called when a channel is deleted from the main interface.
        Parameter is chinfo (a bunch)."""
        chname_del = chinfo.name
        # TODO: delete thumbs for this channel!
        self.logger.info((chname_del) % "deleting thumbs for channel '%s'")
        with self.thmblock:
            self.clear_widget()
            newThumbList = []
            un_hilite_set = set([])
            for thumbkey in self.thumbList:
                chname = thumbkey[0]
                if chname != chname_del:
                    newThumbList.append(thumbkey)
                else:
                    del self.thumbDict[thumbkey]
                    un_hilite_set.add(thumbkey)
            self.thumbList = newThumbList
            self._tkf_highlight -= un_hilite_set  # Unhighlight

        self.reorder_thumbs()
dataset/ETHPy150Open ejeschke/ginga/ginga/misc/plugins/Thumbs.py/Thumbs.delete_channel_cb/swapped operands of `%`