TV_DISPINFO info  Overview  Group

The TV_DISPINFO structure retrieves and sets information about a tree-view item.

typedef struct _TV_DISPINFO {  tvdi 

    NMHDR   hdr; 

    TV_ITEM item; 

} TV_DISPINFO; 

 

Members

hdr

Specifies a NMHDR structure, which enables a tree-view control to pass a pointer to a TV_DISPINFO structure as the lParam parameter of a WM_NOTIFY message.

item

Specifies a TV_ITEM structure that identifies and contains information about the tree-view item. The mask member of the TV_ITEM structure specifies which information is being set or retrieved; it can be one or more of the following values:

Value	Meaning
TVIF_CHILDREN	The cChildren member specifies, or is to receive, a value that indicates whether the item has child items.
TVIF_IMAGE	The iImage member specifies, or is to receive, the index of the item’s non-selected icon in the image list.
TVIF_SELECTEDIMAGE	The iSelectedImage member specifies, or is to receive, the index of the item’s selected icon in the image list.
TVIF_TEXT	The pszText member specifies the new item text or the pointer to a buffer that is to receive the item text.

If the structure is receiving item text, you typically copy the text to the buffer pointed to by the pszText member of the TV_ITEM structure. However, you can return a string in the pszText member instead. If you do so, you cannot change or delete the string until the corresponding item text is deleted or until two additional TVN_GETDISPINFO notification messages have been sent.

Remarks

A pointer to a TV_DISPINFO structure is passed as the lParam parameter when a tree-view control sends a WM_NOTIFY message with the TVN_GETDISPINFO and TVN_SETDISPINFO notification codes. A tree-view control sends these notifications in the following situations in which the parent window of the control stores information about a tree-view item:

• If the pszText member of the item’s TV_ITEM structure is the LPSTR_TEXTCALLBACK value, the control sends these notifications to retrieve or set the item’s text.

• If the iImage or iSelectedImage member of the item’s TV_ITEM structure is the I_IMAGECALLBACK value, the control sends these notifications to retrieve or set the index of an item’s icons in the control’s image list.

• If the cChildren member of the item’s TV_ITEM structure is the I_CHILDRENCALLBACK value, the control sends these notifications to retrieve or set a value that indicates whether the item has child items.

See Also

NMHDR, TV_ITEM, TVN_GETDISPINFO, TVN_SETDISPINFO, WM_NOTIFY