upgrade_contacts_async

Description:

[ Version ( since = "0.19.0" ) ]
public async bool upgrade_contacts_async (Contact[] contacts, ContactFeature[] features, out GenericArray<unowned Contact> contacts_out) throws Error

Given several Contact objects, make asynchronous method calls ensure that all the features specified in features are ready for use (if they are supported at all).

It is not an error to put features in features even if the connection manager doesn't support them - users of this method should have a static list of features they would like to use if possible, and use it for all connection managers.

Parameters:

this	A connection, which must have the `TP_CONNECTION_FEATURE_CONNECTED` feature prepared
contacts	An array of Contact objects associated with this
features	An array of features that must be ready for use (if supported) before the callback is called
callback	A user callback to call when the contacts are ready
n_contacts	The number of contacts in `contacts` (must be at least 1)
n_features	The number of features in `features` (must be at least 1)
user_data	Data to pass to the callback