start.py

from gi.repository import Gtk as gtk
from gi.repository import Gdk as gdk
from settings import IOR

class FlowBoxWindow:
    def __init__(self):
        window = gtk.Window()
        windowMain = gtk.Window()
        windowMain.set_size_request(gdk.Screen.get_default().get_width(),0)
        windowMain.set_name("windowMain")
        windowMain.move(0,0)
        windowMain.set_keep_above(False)
        windowMain.set_resizable(False)
        windowMain.set_decorated(False)
        windowMain.set_border_width(0)
        windowMain.connect("destroy",lambda e: gtk.main_quit())

        boxhMain = gtk.HBox()

        scrolledwindowCategories = gtk.ScrolledWindow()
        scrolledwindowCategories.set_policy(
            gtk.PolicyType.AUTOMATIC,
            gtk.PolicyType.NEVER
            )
        # scrolledwindowCategories.set_size_request(20,20)

        viewportCategories = gtk.Viewport()
        viewportCategories.add(boxhMain)
        scrolledwindowCategories.add(viewportCategories)
        windowMain.add(scrolledwindowCategories)

        notebookCategories = gtk.Notebook()
        boxhMain.add(notebookCategories)

        self.CreateAppMenu(notebookCategories)

        windowMain.show_all()
        gtk.main()


    def CreateAppMenu(self,parent):
        root = IOR.settings["settingsWidgetCategories"]

        for i in range(len([i[0] for i in root])):
        #create container for app buttons#
            boxCategories = gtk.Box()
            boxCategories.set_name("scrolledwindow")
            boxCategories.set_size_request(
                gdk.Screen.get_default().get_width(),
                gdk.Screen.get_default().get_height() - 101
                )

            pixbuffer = gtk.IconTheme.get_default().load_icon(root[i][1],root[i][2],0)
            image = gtk.Image()
            image.set_from_pixbuf(pixbuffer)

            #flowbox area#
            scrolledwindowApps = gtk.ScrolledWindow()
            scrolledwindowApps.set_policy(gtk.PolicyType.NEVER,gtk.PolicyType.AUTOMATIC)

            flowboxApps = gtk.FlowBox()
            flowboxApps.set_valign(gtk.Align.START)
            flowboxApps.set_max_children_per_line(30)
            flowboxApps.set_selection_mode(gtk.SelectionMode.NONE)

            #for j in root:
                #for i in j:
                    #if type(i) is list:
                        #labelAppName = gtk.Label(i[0])
                        #buttonAppName = gtk.Button()
                        #buttonAppName.add(labelAppName)
                        #flowboxApps.add(buttonAppName)

            scrolledwindowApps.add(flowboxApps)
            boxCategories.add(scrolledwindowApps)

            parent.append_page(boxCategories,image)

FlowBoxWindow()