ArcGIS Engine Developer Guide

BUILDING APPLICATIONS WITH C++ AND CONTROL WIDGETS
10. Clean up the transform events in MapViewer.cpp’s CloseAppCallback.
// End event listening
g_ipPageLayoutControlEventHelper->UnadviseEvents();
g_ipPageLayoutControlEventHelper->Shutdown();
g_ipPageLayoutControlEventHelper = 0;
delete g_pageLayoutEvents;
g_ipTOCControlEventHelper->UnadviseEvents();
g_ipTOCControlEventHelper->Shutdown();
g_ipTOCControlEventHelper = 0;
delete g_tocEvents;
g_ipTransEventHelper->UnadviseEvents();
g_ipTransEventHelper->Shutdown();
g_ipTransEventHelper = 0;
delete g_transEvents;
11. Update the makefile to reflect the new source file. Also, add a dependencies
list for TransformEvents.o and add the TransformEvents class to the
PageLayoutControlEvent and MapViewer dependencies lists.
12. To do the actual drawing of the symbol on the MapControl, you need to
listen for the MapControl’s OnAfterDraw event. You will implement an event
class for the MapControl as you have done the PageLayoutControl and
TOCControl. This class will need to know about the global MapControl,
extent, and fill symbol. Start with a new file, MapControlEvents.h:
#ifndef __MAPCONTROLEVENTS_H_
#define __MAPCONTROLEVENTS_H_
// ArcObjects Headers
// Engine
#include
// Controls
#include
extern IMapControl3Ptr g_ipMapControl;
extern IEnvelopePtr g_ipCurrentExtent;
extern IFillSymbolPtr g_ipFillSymbol;
class MapControlEvents : public IMapControlEvents2Helper
{
public:
// IUnknown
IUNKNOWN_METHOD_DEFS
// IMapControlEvents
void OnAfterDraw(VARIANT display, long viewDrawPhase);
void OnAfterScreenDraw(long hdc);
void OnBeforeScreenDraw(long hdc);
void OnDoubleClick(long button, long shift, long x, long y,
double mapX,double mapY);
void OnExtentUpdated(VARIANT displayTransformation,
388 • ArcGIS Engine Developer Guide