SpinButton

A Gtk.SpinButton is an ideal way to allow the user to set the value of some attribute. Rather than having to directly type a number into a Gtk.Entry, Gtk.SpinButton allows the user to click on one of two arrows to increment or decrement the displayed value. A value can still be typed in, with the bonus that it can be checked to ensure it is in a given range. The main properties of a Gtk.SpinButton are set through Gtk.Adjustment.

To change the value that Gtk.SpinButton is showing, use Gtk.SpinButton.props.value. The value entered can either be an integer or float, depending on your requirements, use Gtk.SpinButton.get_value_as_int() or Gtk.SpinButton.get_value(), respectively.

When you allow the displaying of float values in the spin button, you may wish to adjust the number of decimal spaces displayed by calling Gtk.SpinButton.props.digits.

By default, Gtk.SpinButton accepts textual data. If you wish to limit this to numerical values only, set Gtk.SpinButton.props.numeric to True.

We can also adjust the update policy of Gtk.SpinButton. There are two options here; by default the spin button updates the value even if the data entered is invalid. Alternatively, we can set the policy to only update when the value entered is valid by changing Gtk.SpinButton.props.update_policy to Gtk.SpinButtonUpdatePolicy.IF_VALID.

Example

../../_images/spinbutton.png
 1import gi
 2
 3gi.require_version('Gtk', '4.0')
 4from gi.repository import Gtk
 5
 6
 7class SpinButtonWindow(Gtk.ApplicationWindow):
 8    def __init__(self, **kargs):
 9        super().__init__(**kargs, title='SpinButton Demo')
10
11        hbox = Gtk.Box(spacing=6)
12        self.set_child(hbox)
13
14        adjustment = Gtk.Adjustment(
15            upper=100, step_increment=1, page_increment=10
16        )
17        self.spinbutton = Gtk.SpinButton()
18        self.spinbutton.props.adjustment = adjustment
19        self.spinbutton.connect('value-changed', self.on_value_changed)
20        hbox.append(self.spinbutton)
21
22        check_numeric = Gtk.CheckButton(label='Numeric')
23        check_numeric.connect('toggled', self.on_numeric_toggled)
24        hbox.append(check_numeric)
25
26        check_ifvalid = Gtk.CheckButton(label='If Valid')
27        check_ifvalid.connect('toggled', self.on_ifvalid_toggled)
28        hbox.append(check_ifvalid)
29
30    def on_value_changed(self, _scroll):
31        print(self.spinbutton.get_value_as_int())
32
33    def on_numeric_toggled(self, button):
34        self.spinbutton.props.numeric = button.props.active
35
36    def on_ifvalid_toggled(self, button):
37        if button.get_active():
38            policy = Gtk.SpinButtonUpdatePolicy.IF_VALID
39        else:
40            policy = Gtk.SpinButtonUpdatePolicy.ALWAYS
41        self.spinbutton.props.update_policy = policy
42
43
44def on_activate(app):
45    win = SpinButtonWindow(application=app)
46    win.present()
47
48
49app = Gtk.Application(application_id='com.example.App')
50app.connect('activate', on_activate)
51
52app.run(None)