Freezing a custom property

[jeffb]

The documentation for GObject.Object.freeze_notify says:

This method freezes all the “notify::” signals (which are emitted when any property is changed) until the thaw_notify() method is called.

When I run this program:

import gi
gi.require_version('GObject', '2.0')
from gi.repository import GObject

class Freezer(GObject.Object):
    prop = GObject.Property(type=str)

def on_changed(obj, paramspec):
    print('In on_changed, new value =', obj.get_property(paramspec.name))

freezer = Freezer()
print('properties =', [p.name for p in freezer.list_properties()])

freezer.connect('notify::prop', on_changed)

with freezer.freeze_notify():
    freezer.set_property('prop', 'new value')

print('after setting, prop =', freezer.get_property('prop'))

the handler gets called despite the freeze_notify. Am I doing something wrong, or did the documentation fail to mention that freeze_notify does not work with custom properties?

[ebassi (Emmanuele Bassi)]

The handler will be called when the with block terminates, as it will call thaw_notify().

A freeze_notify()/thaw_notify() pair is meant to be used to set multiple properties at the same time, and delay the notification step; additionally, it is used to coalesce multiple notifications on the same property.

[jeffb]

Ah. Now I get it. That is why it is called “freezing” and not “stopping”. Thanks again.