GM_SetChildLayerOpCallback

Sets the function to call to report the load or close of a child layer. This happens during draw or export of a map catalog or online layer. The layer handle provided via the callback can then be used in other function calls that take a layer handle so you can do things like customize vector styles. You can get the parent layer handle by calling GM_GetLayerInfo.

Syntax

C++
Copy 
GM_DLL_EXPORTED void __stdcall GM_SetChildLayerOpCallback
(
GM_ChildLayerOpCallbackFunc aCallbackFunc,
void*                       aUserData       // IN: User data that will be passed back to callback function
);

Remarks

The callback function itself should match the following declaration:

Copy 
typedef void (__stdcall *GM_ChildLayerOpCallbackFunc)
    ( 
    GM_LayerHandle_t32  aChildLayer,    // IN: Handle to new loaded layer
    GM_ChildLayerOp_t8  aChildLayerOp,  // IN: The operation (i.e. load or close) that just happened
    GM_LayerHandle_t32  aParentLayer,   // IN: Handle to new loaded layer's parent
    void*               aUserData,      // IN: User data original provided in call to set this callback
    void*               aReserved       // IN: Reserved for future use
    );