NMHEADERA structure (commctrl.h)

Contains information about header control notification messages. This structure supersedes the HD_NOTIFY structure.

Syntax

typedef struct tagNMHEADERA {
  NMHDR   hdr;
  int     iItem;
  int     iButton;
  HDITEMA *pitem;
} NMHEADERA, *LPNMHEADERA;

Members

hdr

Type: NMHDR

A NMHDR structure that contains information about the notification message.

iItem

Type: int

The zero-based index of the header item that is the focus of the notification message.

iButton

Type: int

A value specifying the index of the mouse button used to generate the notification message. This member can be one of the following values:

Value Meaning
0
Left button
1
Right button
2
Middle button

pitem

Type: HDITEM*

An optional pointer to an HDITEM structure containing information about the item specified by iItem. The mask member of the HDITEM structure indicates which of its members are valid.

Remarks

While most header control notifications pass a pointer to an NMHEADER structure, only some of them use the pitem member to pass an HDITEM structure. Those that do use pitem may not provide complete information about the item. To obtain more information about an item, use HDM_GETITEM.

Note

The commctrl.h header defines NMHEADER as an alias which automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.

Requirements

Requirement Value
Minimum supported client Windows Vista [desktop apps only]
Minimum supported server Windows Server 2003 [desktop apps only]
Header commctrl.h