PANWNDCALLBACK

#include "l_bitmap.h"

L_VOID pEXT_CALLBACK YourFunction(hPanWindow, hWndParent, uFlags, prcPan, pUserData)

HWND hPanWindow;

handle to the Pan Window

HWND hWndParent;

handle to the associated main window

L_UINT uFlags;

Pan Window notification flag

LPRECT prcPan;

pointer to the Pan Rect

L_VOID* pUserData;

pointer to additional parameters

Called to notify the main window of changes to the associated Pan Window.

Parameter Description
hPanWindow Handle to the Pan Window which has changed.
hWndParent Handle to the associated main window.
uFlags Flag indicating the reason for the Pan Window notification. Possible values are:
  Value Meaning
  PANWIN_CREATED [0] Pan Window was created.
  PANWIN_UPDATED [1] Pan Window was updated/repainted.
  PANWIN_DESTROYED [2] Pan Window was destroyed.
  PANWIN_MOVED [3] Pan Window was moved.
  PANWIN_REPAINTED [4] Pan Window was repainted.
prcPan Pointer to a RECT that contains the current coordinates of the Pan Rect in 1:1 zoom factor, when uFlags = PANWIN_UPDATED. Otherwise, this will be NULL. You must convert these coordinates to match your main windows current zoom factor.
pUserData A void pointer that you can use to access a variable or structure containing data that your callback function needs. This gives you a way to receive data indirectly from the function that uses this callback function. (This is the same pointer that you pass in the pUserData parameter of the calling function.)
  Keep in mind that this is a void pointer, which must be cast to the appropriate data type within your callback function.

Returns

None

Comments

This function will be called when the Pan Window updates itself when responding to end-user input, or when the Pan Window repaints itself after being invalidated.

You can use this callback as a notification that the Pan Window has been updated by the end-user. You can also use this function to do your own custom painting in the Pan Window, for example render annotation objects to the Pan Window using the L_AnnDraw function.

You must set a PANWNDCALLBACK callback function when you create the Pan Window using the L_CreatePanWindow function in order to be notified of updates to the Pan Window.

Required DLLs and Libraries

LTDIS

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

See Also

Functions:

L_CreatePanWindow, L_UpdatePanWindow, L_DestroyPanWindow

Example

For an example, refer to L_CreatePanWindow.

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