Find the control surface with a given ID
PtSurface_t *PtFindSurface( PtWidget_t *widget, unsigned char surface_id );
ph
This function locates a control surface belonging to a given widget, using the surface's numerical ID, surface_id, as a search key.
A pointer to the structure representing the control surface, or NULL if the specified surface couldn't be found.
Since control surfaces are maintained internally as an array, it's not uncommon for them to shift around in memory as surfaces are added and removed, thereby possibly invalidating a pointer returned by this function. As such, all surface pointers should be regarded as transient, and you should retrieve an updated copy whenever there's a chance that the widget's surface configuration might have changed. |
Photon
Safety: | |
---|---|
Interrupt handler | No |
Signal handler | No |
Thread | No |
PtFindSurfaceByAction(), PtWidgetActiveSurface()
Control Surfaces chapter of the Photon Programmer's Guide