| Bonobo API Reference Manual | |||
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struct BonoboMonikerExtender; typedef BonoboMonikerExtenderClass; |
A moniker extender is used to extend the functionality of a moniker. There are two standard moniker extenders that cannot be system wide, since they use the oaf database to expand the scope of a moniker to arbitrarily many interfaces. These are invoked explicitely by monikers implementing the stream interface in the following way:
Example 1. Explicit Stream extender usage example
Bonobo_Unknown
example_moniker_resolve (BonoboMoniker *moniker,
const Bonobo_ResolveOptions *options,
const CORBA_char *requested_interface,
CORBA_Environment *ev)
{
if (!strcmp (requested_interface, "IDL:Bonobo/Stream:1.0"))
return handle_stream (moniker, options, ev);
else
return bonobo_moniker_use_extender (
"OAFIID:Bonobo_MonikerExtender_stream",
moniker, options, requested_interface, ev);
}
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All standard moniker extenders are registered by adding a fragment like this:
Example 2. Oaf information for an extender
<oaf_attribute name="bonobo:moniker_extender" type="stringv">
<item value="file:"/>
</oaf_attribute>
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Implementing your own extender is extremely simple, much like
Example 3. Oaf information for an extender
Bonobo_Unknown
example_extender_resolve (BonoboMonikerExtender *extender,
const Bonobo_Moniker m,
const Bonobo_ResolveOptions *options,
const CORBA_char *display_name,
const CORBA_char *requested_interface,
CORBA_Environment *ev)
{
... resolve 'm' against an interface we know it supports ...
... then use that interface to provide requested_interface ...
}
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Example 4. Creating a new simple moniker
static BonoboObject *
bonobo_std_moniker_factory (BonoboGenericFactory *this,
const char *object_id,
void *data)
{
g_return_val_if_fail (object_id != NULL, NULL);
if (!strcmp (object_id, "OAFIID:Bonobo_MonikerExtender_file"))
return BONOBO_OBJECT (bonobo_moniker_extender_new (
example_extender_resolve, NULL));
else
return NULL;
}
|
typedef struct {
BonoboXObjectClass parent_class;
POA_Bonobo_MonikerExtender__epv epv;
BonoboMonikerExtenderFn resolve;
} BonoboMonikerExtenderClass; |
|
| extender : | |
| parent : | |
| options : | |
| display_name : | |
| requested_interface : | |
| ev : | |
| Returns : |
|
|
This creates a new moniker extender.
| resolve : | the resolve function that will be used to do the extension |
| data : | user data to be passed back to the resolve function. |
| Returns : | the extender object |
|
This routine tries to locate an extender for our moniker by examining a registry of extenders that map new interfaces to certain moniker names.
| name : | the name of the moniker we want to extend eg. 'file:' |
| interface : | the interface we want to resolve to |
| ev : | a corba exception environment. |
| Returns : | an appropriate extender or CORBA_OBJECT_NIL. |
|
Locates a known extender via. OAFIID; eg. OAFIID:Bonobo_Moniker_Extender_file
| extender_oafiid : | The IID of the extender to use |
| moniker : | the moniker to extend |
| options : | resolve options |
| requested_interface : | the requested interface |
| ev : | corba environment |
| Returns : | the resolved result or CORBA_OBJECT_NIL. |