def add_channel_cb(self, viewer, channel):
        chname = channel.name

        # add old highlight set to channel external data
        channel.extdata.setdefault('contents_old_highlight', set([]))

        # Add the channel to the treeview
        file_dict = {}
        self.name_dict.setdefault(chname, file_dict)

        if not self.gui_up:
            return False

        tree_dict = { chname: { } }
        self.treeview.add_tree(tree_dict)
Called when a channel is added from the main interface.
dataset/ETHPy150Open ejeschke/ginga/ginga/misc/plugins/Contents.py/Contents.add_channel_cb