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DISPCONTAINERACTIONCALLBACK

Summary

This callback function is called each time the user clicks or drags the mouse, rotates the mouse wheel, or presses a keyboard button, if the mouse or keyboard event is associated with a user-defined action.

Syntax

#include "ltivw.h"

L_INT pEXT_CALLBACK YourFunction(phBitmapList, uCount, nAction, uMessage, wParam, ptMousePos, pUserData)

Parameters

HBITMAPLIST * phBitmapList

An array of bitmap lists that represent all the bitmap lists of all cells selected by the user.

L_UINT uCount

The number of bitmap lists referenced by phBitmapList.

L_INT nAction

Value that indicates the action associated with the mouse or keyboard event. Since this callback is used for user-defined actions, this value should be >= 100. Otherwise, it can be one of the following predefined actions:

Value	Meaning
CONTAINER_ACTION_WINDOWLEVEL	[1] Window leveling
CONTAINER_ACTION_SCALE	[2] Scaling
CONTAINER_ACTION_OFFSET	[3] Offset
CONTAINER_ACTION_STACK	[4] Stacking
CONTAINER_ACTION_MAG	[5] Magnifying glass
CONTAINER_ACTION_ALPHA	[6] Alpha
CONTAINER_ACTION_ANNOTATION_RULER	[7] Ruler annotation
CONTAINER_ACTION_ANNOTATION_ANGLE	[8] Angle annotation
CONTAINER_ACTION_ANNOTATION_TEXT	[9] Text annotation
CONTAINER_ACTION_ANNOTATION_ARROW	[10] Arrow annotation
CONTAINER_ACTION_ANNOTATION_RECTANGLE	[11] Rectangle annotation
CONTAINER_ACTION_ANNOTATION_ELLIPSE	[12] Ellipse annotation
CONTAINER_ACTION_ANNOTATION_HILITE	[13] Highlight annotation
CONTAINER_ACTION_REGION_RECTANGLE	[14] Rectangular region
CONTAINER_ACTION_REGION_ELLIPSE	[15] Elliptical region
CONTAINER_ACTION_REGION_FREEHAND	[16] Free hand region
CONTAINER_ACTION_REGION_POLYGON	[17] Polygon region
CONTAINER_ACTION_REGION_MAGICWAND	[18] Magic wand (contiguous color) region
CONTAINER_ACTION_REGION_COLORRANGE	[19] Color range region
CONTAINER_ACTION_REGION_CIRCLE	[20] Circular region
CONTAINER_ACTION_REGION_SQUARE	[21] Square region
CONTAINER_ACTION_REGION_NUDGETOOL	[22] Nudge tool.
CONTAINER_ACTION_REGION_SHRINKTOOL	[23] Shrink tool.

L_UINT uMessage

Value that represents the message from either the mouse or the keyboard. Possible values are:

WM_KEYDOWN WM_KEYUP WM_LBUTTONDOWN WM_LBUTTONUP WM_MBUTTONDOWN WM_MBUTTONUP WM_XBUTTONDOWN WM_XBUTTONUP WM_MOUSEMOVE WM_MOUSEWHEEL WM_RBUTTONDOWN WM_RBUTTONUP

WPARAM wParam

Additional message information.

POINT * ptMousePos

A point that represents the position of the cursor.

L_VOID * 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 L_DispContainerCreate) Keep in mind that this is a void pointer, which must be cast to the appropriate data type within your callback function.

Returns

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

Comments

A user-defined action is added to a container by calling L_DispContainerSetAction. If a mouse or keyboard event that is associated with a user-defined action occurs, this callback function is called to allow the user to handle the action.

In order to use this callback function, it must first be set by calling L_DispContainerSetActionCallback.