Label in Python GTK+ 3

Labels are the main method of placing non-editable text in windows. For example, label can be used as a title placed next to entry widget. Some of the important features of the label are –

• The selection of labels can be done using Gtk.Label.set_selectable(). Selectable labels allow the user to copy the contents to the clipboard. Labels contain useful information to copied such as error messages that can be made as a selectable label.
• Label text justification and word-wrapping are possible by the methods Gtk.Label.set_justify(), Gtk.Label.set_line_wrap() respectively.
• Also, Gtk.Label supports clickable hyperlinks. The markup for links is borrowed from HTML, using the a with href and title attributes. GTK+ renders links similar to the way they appear in web browsers, with colored, underlined text.
• Mnemonics are the underlined characters in the label, used for keyboard navigation; can be created by giving a string with an underscore before the mnemonic character, such as “_Geeks For Geeks” to the function Gtk.Label.set_text_with_mnemonic().

To create a label follow the below steps:

1. import GTK+ 3 module.
2. Create main window.
3. Create a Box.
4. Implement Label.
5. Implement Button.

Example :

import gi

gi.require_version("Gtk", "3.0")
from gi.repository import Gtk


class LabelWindow(Gtk.Window):

    def __init__(self):
        Gtk.Window.__init__(self, title ="Label Example")

        # Create Box
        hbox = Gtk.Box(spacing = 10)
        hbox.set_homogeneous(False)
        vbox_left = Gtk.Box(orientation = Gtk.Orientation.VERTICAL,
                    spacing = 10)
        vbox_left.set_homogeneous(False)
        vbox_right = Gtk.Box(orientation = Gtk.Orientation.VERTICAL,
                    spacing = 10)
        vbox_right.set_homogeneous(False)

        hbox.pack_start(vbox_left, True, True, 0)
        hbox.pack_start(vbox_right, True, True, 0)

        # Create label
        label = Gtk.Label("Normal label")
        vbox_left.pack_start(label, True, True, 0)

        # Create justified label
        # with multiple lines
        label = Gtk.Label("Example for "
                "Right-justified label.\n"
                "having multiple lines.")
        label.set_justify(Gtk.Justification.RIGHT)
        vbox_left.pack_start(label, True, True, 0)

        label = Gtk.Label(
            "Example for a line-wrapped label."

        )
        label.set_line_wrap(True)
        vbox_right.pack_start(label, True, True, 0)

        label = Gtk.Label(
            "Example for a line-wrapped filled label. "
        )
        label.set_line_wrap(True)
        label.set_justify(Gtk.Justification.FILL)
        vbox_right.pack_start(label, True, True, 0)

        # Create label markup
        label = Gtk.Label()
        label.set_markup(
            "To go to <b>Geeks</b> "
            "<small>For</small> <i>Geeks</i> "
            '<a href ="https://www.geeksforgeeks.org/" '
            'title ="">Click here</a>.'
        )
        label.set_line_wrap(True)
        vbox_left.pack_start(label, True, True, 0)

        # Create label mnemonic
        label = Gtk.Label.new_with_mnemonic(
            "_Press -> to click the right button to exit"
        )
        vbox_left.pack_start(label, True, True, 0)
        label.set_selectable(True)

        # Create Button
        button = Gtk.Button(label ="Exit")
        label.set_mnemonic_widget(button)
        vbox_right.pack_start(button, True, True, 0)

        self.add(hbox)


window = LabelWindow()
window.connect("destroy", Gtk.main_quit)

# Display the window.
window.show_all()

# Start the GTK + processing loop
Gtk.main()

Output :