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_CHILDREN | query/set the IDs of the side panes |
| SPLITMP_CHILDHWND | query/set the window handle of a child pane |
| SPLITMP_PANERECT | query a pane or the whole splitpane coordinates |
| SPLITMP_PANEPOSSIZE | query a pane or the whole splitpane position and size |
| SPLITMP_BARPOS | query/set the splitter position |
| SPLITMP_BARTHICKNESS | query/set the splitter thickness |
| SPLITMP_MINWIDTHHEIGHT | query/set the minimum width/height of a pane |
| SPLITMP_STYLE | query/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_WHOLEPANE | the whole splitpane |
| SPLITMP_PANE1 | the left/top pane |
| SPLITMP_PANE2 | the right/bottom pane |
| minimum width/height query/set scope: | |
| SPLITMP_LEFT | the left pane (column division i.e. vertical splitter) |
| SPLITMP_TOP | the top pane (row division i.e. horizontal splitter) |
| SPLITMP_RIGHT | the right pane (column division i.e. vertical splitter) |
| SPLITMP_BOTTOM | the 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.