PM messages

The splitpane control uses just two PM messages to query or set its properties, SPLITM_QUERY and SPLITM_SET.

The first short of the first message parameter specifies the property which is being queried or set:

SPLITMP_CHILDRENquery/set the IDs of the side panes
SPLITMP_CHILDHWNDquery/set the window handle of a child pane
SPLITMP_PANERECTquery a pane or the whole splitpane coordinates
SPLITMP_PANEPOSSIZEquery a pane or the whole splitpane position and size
SPLITMP_BARPOSquery/set the splitter position
SPLITMP_BARTHICKNESSquery/set the splitter thickness
SPLITMP_MINWIDTHHEIGHTquery/set the minimum width/height of a pane
SPLITMP_STYLEquery/set the splitpane style

The second short of the first message parameter is used when a given properties may apply to different splitpane parts and specifies the property scope:

coordinate or size-position request scope:
SPLITMP_WHOLEPANEthe whole splitpane
SPLITMP_PANE1the left/top pane
SPLITMP_PANE2the right/bottom pane
minimum width/height query/set scope:
SPLITMP_LEFTthe left pane (column division i.e. vertical splitter)
SPLITMP_TOPthe top pane (row division i.e. horizontal splitter)
SPLITMP_RIGHTthe right pane (column division i.e. vertical splitter)
SPLITMP_BOTTOMthe bottom pane (row division i.e. horizontal splitter)

The axSplitpane.h file, anyway, contains the definition of a complete set of macros which allow to query or set all the available properties in a much more comfortable way.