Поиск Item’а в TreeView

Поиск Item'а в TreeView

(how to find an item in a tree control via its label)
the "tree view" common control does not have any built-in method for searching the entire tree, or for selecting an item contained within the tree when given a specific item label. this article provides code that returns the location of any item in a tree when given a specific label to search for.

the getitembyname() function takes the window handle of the tree control, htreeitem, which points to the item in the tree to start searching and a string for which to search.

unit unit1;
interface
uses
windows, messages, sysutils, classes, graphics, controls, forms, dialogs,
stdctrls, comctrls;
type
tform1 = class(tform)
button1: tbutton;
treeview1: ttreeview;
procedure button1click(sender: tobject);
private
{ private declarations }
public
{ public declarations }
end;
var
form1: tform1;

implementation
{$r *.dfm}
uses  commctrl;

// note: if you have items with more than 50 characters
// of text, you'll need to increase this value.
const maxtextlen=50;

function getitembyname(wnd : hwnd;  hitem : htreeitem; szitemname : lpctstr) : htreeitem ;
var  szbuffer: array [0..maxtextlen+1] of char;
item : ttvitem;
hitemfound, hitemchild : htreeitem;
begin
// if hitem is null, start search from root item.
if (hitem = nil) then
hitem := htreeitem(sendmessage(wnd, tvm_getnextitem, tvgn_root, 0));
while (hitem <> nil) do
begin
item.hitem := hitem;
item.mask := tvif_text or tvif_children;
item.psztext := szbuffer;
item.cchtextmax := maxtextlen;
sendmessage(wnd, tvm_getitem, 0, longint(@item));
// did we find it?
if (lstrcmp(szbuffer, szitemname) = 0) then
begin
result := hitem;
exit;
end;
// check whether we have child items.
if (item.cchildren > 0) then
begin
// recursively traverse child items.
hitemchild := htreeitem(sendmessage(wnd, tvm_getnextitem, tvgn_child, longint(hitem)));
hitemfound := getitembyname(wnd, hitemchild, szitemname);
// did we find it?
if (hitemfound <> nil) then
begin
result :=  hitemfound;
exit;
end;
end;
// go to next sibling item.
hitem := htreeitem(sendmessage(wnd, tvm_getnextitem, tvgn_next, lparam(hitem)));
end;
// not found.
result := nil;
end;

procedure tform1.button1click(sender: tobject);
var  hitem : htreeitem;
begin
hitem := getitembyname(treeview1.handle, nil, 'serge');
if (hitem <> nil) then
begin
treeview1.setfocus;
sendmessage(treeview1.handle, tvm_selectitem, tvgn_caret,  longint(hitem));
end;
end;
end.

Эта запись была добавлена в Пятница, 23 мая, 2008 - 11:10 В разделы TreeView, Компоненты. Вы можете подписаться на получение новых комментариев RSS 2.0 feed. Both comments and pings are currently closed.