PtSurfaceGetData()

Get data associated with a control surface

Synopsis:

void *PtSurfaceGetData( PtWidget_t *widget,
                        PtSurface_t *surface );

void *PtSurfaceGetDataById( PtWidget_t *widget,
                            unsigned char surface_id );

Library:

ph

Description:

These functions retrieve the user data stored with a control surface belonging to the given widget. They differ in the way they identify the control surface:

PtSurfaceGetData(): Uses the surface argument, which points to a PtSurface_t structure that describes the control surface. This pointer must not be NULL.
PtSurfaceGetDataById(): Searches the control surfaces belonging to the widget for the one with an ID of surface_id.

Returns:

A pointer to the data, or NULL if either the specified surface couldn't be found, or it doesn't have any data attached to it.

Classification:

Photon

Safety:
Interrupt handler	No
Signal handler	No
Thread	No

See also:

PtSurfaceAddData(), PtSurfaceAddDataById(), PtSurfaceRemoveData(), PtSurfaceRemoveDataById()

Control Surfaces chapter of the Photon Programmer's Guide