What is the reason for such black bars in GUI?

[j_arun_mani]

Im designing an application for my project but the window has some black colour space appearing as shown in pic. The hierarchy for widgets are as folllows:

         1. grid -
                  1.1. combo box
                  1.2. grid -
                           1.2.1. label, entry
                           1.2.2. label, entry
                           1.2.3. label, entry
                           1.2.4. expander -
                                    1.2.4.1. grid -
                                             1.2.4.1.1. label, entry
                                             1.2.4.1.2. label, entry
                  1.3. label

Is it due to the complex nature of way elements are packed?

A minimial working example is

from gi.repository import Gtk

dialog = Gtk.Window(name="dialog")
main_grid = Gtk.Grid(name="dialog-main_grid",
                     hexpand=True,
                     halign=Gtk.Align.FILL)
connectors_combobox = Gtk.ComboBoxText(name="connectors_combobox",
                                                    active_id=0)
entry_grid = Gtk.Grid(name="entry_grid",
                      hexpand=True,
                      halign=Gtk.Align.FILL)
error_label = Gtk.Label(name="error_label",
                        label="Error",
                        use_markup=True)

entry_grid.attach(Gtk.Label(label="Label 1"), 0, 0, 1, 1)
entry_grid.attach(Gtk.Entry(text="Entry 1"), 0, 1, 1, 1)
entry_grid.attach(Gtk.Label(label="Label 2"), 0, 2, 1, 1)
entry_grid.attach(Gtk.Entry(text="Entry 2"), 0, 3, 1, 1)
entry_grid.attach(Gtk.Label(label="Label 3"), 0, 4, 1, 1)
entry_grid.attach(Gtk.Entry(text="Entry 3"), 0, 5, 1, 1)

#connect_button = Gtk.Button(name="login-dialog-connect",
#                                         label="Connect")
#quit_button = Gtk.Button(name="login-dialog-quit",
#                                      label="Quit")
#connect_button.connect("clicked", response, 1)
#quit_button.connect("clicked", response, 0)

#connectors_combobox.connect("changed", show_prompts)
    
main_grid.attach(connectors_combobox, 0, 0, 1, 1)
main_grid.attach(entry_grid, 0, 1, 1, 1)
main_grid.attach(error_label, 0, 2, 1, 1)

#main_grid.attach(connect_button, 0, 3, 1, 1)
#main_grid.attach(quit_button, 1, 3, 1, 1)
dialog.add(main_grid)
dialog.show_all()
dialog.connect("destroy", Gtk.main_quit)
Gtk.main()

[cecashon (C. Eric Cashon)]

The black labels are from the theme that you are using. Test running the program with

GTK_THEME=Adwaita:dark python3 program.py

or

GTK_THEME=Adwaita:light python3 program.py

or change the CSS in your program to color the labels differently.

Eric

[j_arun_mani]

Thanks. It seems weird, such black labels only appear when I pack containers inside containers and so and not in ordinary cases, anyway, I like your idea. Thanks again ^^