L_AnnUndo

#include "l_bitmap.h"

L_LTANN_API L_INT L_AnnUndo(hObject)

/* handle to the automation object */

Reverses the last user action that was executed using the automated annotation functions.

Parameter	Description
hObject	Handle to the automation object.

Returns

SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

This function can be used repeatedly to reverse the number of actions specified by the L_AnnSetUndoDepth function. When the stack is empty, it returns an error.

There is only one undo depth value per root container. (Subcontainers do not have their own separate values.)

Required DLLs and Libraries

LTANN

For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Platforms

Win32, x64.

See Also

Functions:	L_AnnCreate, L_AnnSetAutoContainer, L_AnnGetAutoContainer, L_AnnSetDpiX, L_AnnSetDpiY, L_AnnGetDpiX, L_AnnGetDpiY, L_AnnSetTool, L_AnnGetTool, L_AnnGetUserMode, L_AnnSetUserMode, L_AnnSetUndoDepth, L_AnnAddUndoNode, L_AnnGetAutoUndoEnable, L_AnnSetAutoUndoEnable
Topics:	Annotation Functions: Working with the Toolbar
	Implementing Annotations
	Automated User Interface for Annotations
	Implementing an Automated Annotation Program

Example

/* This example reverses the last user action in automation mode. */
 L_INT AnnUndoExample(HANNOBJECT hAutoObject)/* Automation object */
{
   L_INT nRet;
   L_UINT uUndoLevels;

   nRet = L_AnnGetUndoDepth(hAutoObject, &uUndoLevels, NULL);
   if(nRet != SUCCESS)
      return nRet;
   if(uUndoLevels)
   {
      nRet = L_AnnUndo(hAutoObject);
      if(nRet != SUCCESS)
         return nRet;
   }
   else
      MessageBox(NULL, TEXT("No undo operation possible!"), TEXT("Undo"), MB_OK);
   return SUCCESS;
}