Class: Gio::SettingsBackend

Inherits:
Object
  • Object
show all
Defined in:
(unknown)

Overview

Class structure for GSettings::Backend.

Instance Method Summary collapse

Instance Method Details

#changed(key, origin_tag) ⇒ nil

Signals that a single key has possibly changed. Backend implementations should call this if a key has possibly changed its value.

key must be a valid key (ie starting with a slash, not containing ‘//’, and not ending with a slash).

The implementation must call this function during any call to g_settings_backend_write(), before the call returns (except in the case that no keys are actually changed and it cares to detect this fact). It may not rely on the existence of a mainloop for dispatching the signal later.

The implementation may call this function at any other time it likes in response to other events (such as changes occurring outside of the program). These calls may originate from a mainloop or may originate in response to any other action (including from calls to g_settings_backend_write()).

In the case that this call is in response to a call to g_settings_backend_write() then origin_tag must be set to the same value that was passed to that call.

Parameters:

  • key (String) —

    the name of the key

  • origin_tag (GObject) —

    the origin tag

Returns:

  • (nil)

#changed_tree(tree, origin_tag) ⇒ nil

This call is a convenience wrapper. It gets the list of changes from tree, computes the longest common prefix and calls g_settings_backend_changed().

Parameters:

  • tree (GLib::Tree) —

    a #GTree containing the changes

  • origin_tag (GObject) —

    the origin tag

Returns:

  • (nil)

#keys_changed(path, items, origin_tag) ⇒ nil

Signals that a list of keys have possibly changed. Backend implementations should call this if keys have possibly changed their values.

path must be a valid path (ie starting and ending with a slash and not containing ‘//’). Each string in items must form a valid key name when path is prefixed to it (ie: each item must not start or end with ‘/’ and must not contain ‘//’).

The meaning of this signal is that any of the key names resulting from the contatenation of path with each item in items may have changed.

The same rules for when notifications must occur apply as per g_settings_backend_changed(). These two calls can be used interchangeably if exactly one item has changed (although in that case g_settings_backend_changed() is definitely preferred).

For efficiency reasons, the implementation should strive for path to be as long as possible (ie: the longest common prefix of all of the keys that were changed) but this is not strictly required.

Parameters:

  • path (String) —

    the path containing the changes

  • items (Array<String>) —

    the nil-terminated list of changed keys

  • origin_tag (GObject) —

    the origin tag

Returns:

  • (nil)

#path_changed(path, origin_tag) ⇒ nil

Signals that all keys below a given path may have possibly changed. Backend implementations should call this if an entire path of keys have possibly changed their values.

path must be a valid path (ie starting and ending with a slash and not containing ‘//’).

The meaning of this signal is that any of the key which has a name starting with path may have changed.

The same rules for when notifications must occur apply as per g_settings_backend_changed(). This call might be an appropriate reasponse to a ‘reset’ call but implementations are also free to explicitly list the keys that were affected by that call if they can easily do so.

For efficiency reasons, the implementation should strive for path to be as long as possible (ie: the longest common prefix of all of the keys that were changed) but this is not strictly required. As an example, if this function is called with the path of “/” then every single key in the application will be notified of a possible change.

Parameters:

  • path (String) —

    the path containing the changes

  • origin_tag (GObject) —

    the origin tag

Returns:

  • (nil)

#path_writable_changed(path) ⇒ nil

Signals that the writability of all keys below a given path may have changed.

Since GSettings performs no locking operations for itself, this call will always be made in response to external events.

Parameters:

  • path (String) —

    the name of the path

Returns:

  • (nil)

#writable_changed(key) ⇒ nil

Signals that the writability of a single key has possibly changed.

Since GSettings performs no locking operations for itself, this call will always be made in response to external events.

Parameters:

  • key (String) —

    the name of the key

Returns:

  • (nil)