set_cached_property


Description:

public void set_cached_property (string property_name, Variant? value)

If value is not null, sets the cached value for the property with name property_name to the value in value.

If value is null, then the cached value is removed from the property cache.

If this has an expected interface (see g_interface_info) and property_name is referenced by it, then value is checked against the type of the property.

If the value Variant is floating, it is consumed. This allows convenient 'inline' use of Variant, e.g.

 g_dbus_proxy_set_cached_property (proxy,
"SomeProperty",
g_variant_new ("(si)",
"A String",
42));

Normally you will not need to use this method since this is tracking changes using the `org.freedesktop.DBus.Properties.PropertiesChanged` D-Bus signal. However, for performance reasons an object may decide to not use this signal for some properties and instead use a proprietary out-of-band mechanism to transmit changes.

As a concrete example, consider an object with a property `ChatroomParticipants` which is an array of strings. Instead of transmitting the same (long) array every time the property changes, it is more efficient to only transmit the delta using e.g. signals `ChatroomParticipantJoined(String name)` and `ChatroomParticipantParted(String name)`.

Parameters:

this

A DBusProxy

property_name

Property name.

value

Value for the property or null to remove it from the cache.




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