Creating a Tree View Control

To create a tree view control in C, use the CreateWindow or CreateWindowEx function and specify the WC_TREEVIEW style for the window class. If you are using MFC, create a CTreeCtrl object by using the Create member function. The following code produces a tree view control and uses the image list functions to create an image list associated with it:

HWND CreateTreeView (HWND hWndParent)

{

HWND hwndTree; // handle to tree view window

RECT rcl; // rectangle for setting size of window

HBITMAP hBmp; // handle to a bitmap

HIMAGELIST hIml; // handle to image list



// Ensure that the common control DLL is loaded.

InitCommonControls ();



// Get the size and position of the parent window.

GetClientRect (hWndParent, &rcl);



// Create the tree view window.

hwndTree = CreateWindowEx (

0L,

WC_TREEVIEW, // tree view class

"", // no default text

WS_VISIBLE | WS_CHILD | WS_BORDER | TVS_HASLINES | TVS_HASBUTTONS
| 

TVS_LINESATROOT,

0, 0,

rcl.right - rcl.left, rcl.bottom - rcl.top - 15,

hWndParent,

(HMENU)ID_TREEVIEW,

hInst,

NULL);



if (hwndTree == NULL)

return NULL;



// Initialize the tree view window.

// First create the image list you will need.

hIml = ImageList_Create (

BITMAP_WIDTH, // width

BITMAP_HEIGHT, // height

0, // creation flags

NUM_BITMAPS, // number of images

0); // amount this list can grow



// Load the bitmaps and add them to the image list.

hBmp = LoadBitmap (hInst, MAKEINTRESOURCE (FORSALE));

idxForSale = ImageList_Add (

hIml, // handle to image list

hBmp) // handle of bitmap to add

NULL); // handle of bitmap mask



hBmp = LoadBitmap (hInst, MAKEINTRESOURCE (REDMOND));

idxRedmond = ImageList_Add (hIml, hBmp, NULL);



hBmp = LoadBitmap (hInst, MAKEINTRESOURCE (BELLEVUE));

idxBellevue = ImageList_Add (hIml, hBmp, NULL);



hBmp = LoadBitmap (hInst, MAKEINTRESOURCE (SEATTLE));

idxSeattle = ImageList_Add (hIml, hBmp, NULL);



// Be sure that all the bitmaps were added.

if (ImageList_GetImageCount (hIml) < NUM_BITMAPS)

return FALSE;



// Associate the image list with the tree view control.

TreeView_SetImageList (hwndTree, hIml, idxForSale);



return hwndTree;

}