This is a convenience function to return a default Source based on extension_name.
This only works with a subset of extension names.
If extension_name is SOURCE_EXTENSION_ADDRESS_BOOK, the
function returns the current default address book, or else falls back to the built-in address book.
If extension_name is SOURCE_EXTENSION_CALENDAR, the function
returns the current default calendar, or else falls back to the built-in calendar.
If extension_name is SOURCE_EXTENSION_MAIL_ACCOUNT, the
function returns the current default mail account, or else falls back to the built-in mail account.
If extension_name is SOURCE_EXTENSION_MAIL_IDENTITY,
the function returns the current default mail identity, or else falls back to the mail identity named by the current default mail account.
If extension_name is SOURCE_EXTENSION_MEMO_LIST, the
function returns the current default memo list, or else falls back to the built-in memo list.
If extension_name is SOURCE_EXTENSION_TASK_LIST, the
function returns the current default task list, or else falls back to the built-in task list.
For all other values of extension_name, the function returns null.
The returned Source is referenced for thread-safety and must be unreferenced with unref when finished with it.
| this | |
| extension_name |
an extension_name |
|
the default Source based on |