unit HETreeView;
{$R-}
// Pasted from UDDF
// Made by: H?kon Eines
// EMail: haakon.eines@finale.no
// Date: 21.01.1997
// Description: A Speedy TreeView?
(*
TTREEVIEW:
128 sec. to load 1000 items (no sorting)*
270 sec. to save 1000 items (4.5 minutes!!!)
THETREEVIEW:
1.5 sec. to load 1000 items - about 850% faster!!! (2.3 seconds with sorting = stText)*
0.7 sec. to save 1000 items - about 3850% faster!!!
NOTES:
- All timings performed on a slow 486SX 33 MhZ, 20 Mb RAM.
- * If the treeview is empty, loading takes 1.5 seconds,
else add 1.5 seconds to clear 1000 items (a total loading time of 3 seconds).
This is also the case for the TTreeView component (a total of 129.5 seconds).
The process of clearing the items, is a call to
SendMessage(hwnd, TVM_DELETEITEM, 0, Longint(TVI_ROOT)).
*)
interface
uses
SysUtils, Windows, Messages, Classes, Graphics,
Controls, Forms, Dialogs, ComCtrls, CommCtrl;
type
THETreeView = class(TTreeView)
private
FSortType: TSortType;
procedure SetSortType(Value: TSortType);
protected
function GetItemText(ANode: TTreeNode): string;
public
constructor Create(AOwner: TComponent); override;
function AlphaSort: Boolean;
function CustomSort(SortProc: TTVCompare; Data: Longint): Boolean;
procedure LoadFromFile(const AFileName: string);
procedure SaveToFile(const AFileName: string);
procedure GetItemList(AList: TStrings);
procedure SetItemList(AList: TStrings);
//'Bold' should have been a property of TTreeNode, but...
function IsItemBold(ANode: TTreeNode): Boolean;
procedure SetItemBold(ANode: TTreeNode; Value: Boolean);
published
property SortType: TSortType read FSortType write SetSortType default stNone;
end;
procedure Register;
implementation
function DefaultTreeViewSort(Node1, Node2: TTreeNode; lParam: Integer): Integer; stdcall;
begin
{with Node1 do
if Assigned(TreeView.OnCompare) then
TreeView.OnCompare(Node1.TreeView, Node1, Node2, lParam, Result)
else}
Result := lstrcmp(PChar(Node1.Text), PChar(Node2.Text));
end;
constructor THETreeView.Create(AOwner: TComponent);
begin
inherited Create(AOwner);
FSortType := stNone;
end;
procedure THETreeView.SetItemBold(ANode: TTreeNode; Value: Boolean);
var
Item: TTVItem;
Template: Integer;
begin
if ANode = nil then Exit;
if Value then Template := -1
else Template := 0;
with Item do
begin
mask := TVIF_STATE;
hItem := ANode.ItemId;
stateMask := TVIS_BOLD;
state := stateMask and Template;
end;
TreeView_SetItem(Handle, Item);
end;
function THETreeView.IsItemBold(ANode: TTreeNode): Boolean;
var
Item: TTVItem;
begin
Result := False;
if ANode = nil then Exit;
with Item do
begin
mask := TVIF_STATE;
hItem := ANode.ItemId;
if TreeView_GetItem(Handle, Item) then
Result := (state and TVIS_BOLD) <> 0;
end;
end;
procedure THETreeView.SetSortType(Value: TSortType);
begin
if SortType <> Value then
begin
FSortType := Value;
if ((SortType in [stData, stBoth]) and Assigned(OnCompare)) or
(SortType in [stText, stBoth]) then
AlphaSort;
end;
end;
procedure THETreeView.LoadFromFile(const AFileName: string);
var
AList: TStringList;
begin
AList := TStringList.Create;
Items.BeginUpdate;
try
AList.LoadFromFile(AFileName);
SetItemList(AList);
finally
Items.EndUpdate;
AList.Free;
end;
end;
procedure THETreeView.SaveToFile(const AFileName: string);
var
AList: TStringList;
begin
AList := TStringList.Create;
try
GetItemList(AList);
AList.SaveToFile(AFileName);
finally
AList.Free;
end;
end;
procedure THETreeView.SetItemList(AList: TStrings);
var
ALevel, AOldLevel, i, Cnt: Integer;
S: string;
ANewStr: string;
AParentNode: TTreeNode;
TmpSort: TSortType;
function GetBufStart(Buffer: PChar; var ALevel: Integer): PChar;
begin
ALevel := 0;
while Buffer^ in [' ', #9] do
begin
Inc(Buffer);
Inc(ALevel);
end;
Result := Buffer;
end;
begin
//Delete all items - could have used Items.Clear (almost as fast)
SendMessage(handle, TVM_DELETEITEM, 0, Longint(TVI_ROOT));
AOldLevel := 0;
AParentNode := nil;
//Switch sorting off
TmpSort := SortType;
SortType := stNone;
try
for Cnt := 0 to AList.Count-1 do
begin
S := AList[Cnt];
if (Length(S) = 1) and (S[1] = Chr($1A)) then Break;
ANewStr := GetBufStart(PChar(S), ALevel);
if (ALevel > AOldLevel) or (AParentNode = nil) then
begin
if ALevel - AOldLevel > 1 then raise Exception.Create('Invalid TreeNode Level');
end
else begin
for i := AOldLevel downto ALevel do
begin
AParentNode := AParentNode.Parent;
if (AParentNode = nil) and (i - ALevel > 0) then
raise Exception.Create('Invalid TreeNode Level');
end;
end;
AParentNode := Items.AddChild(AParentNode, ANewStr);
AOldLevel := ALevel;
end;
finally
//Switch sorting back to whatever it was...
SortType := TmpSort;
end;
end;
procedure THETreeView.GetItemList(AList: TStrings);
var
i, Cnt: integer;
ANode: TTreeNode;
begin
AList.Clear;
Cnt := Items.Count -1;
ANode := Items.GetFirstNode;
for i := 0 to Cnt do
begin
AList.Add(GetItemText(ANode));
ANode := ANode.GetNext;
end;
end;
function THETreeView.GetItemText(ANode: TTreeNode): string;
begin
Result := StringOfChar(' ', ANode.Level) + ANode.Text;
end;
function THETreeView.AlphaSort: Boolean;
var
I: Integer;
begin
if HandleAllocated then
begin
Result := CustomSort(nil, 0);
end
else Result := False;
end;
function THETreeView.CustomSort(SortProc: TTVCompare; Data: Longint): Boolean;
var
SortCB: TTVSortCB;
I: Integer;
Node: TTreeNode;
begin
Result := False;
if HandleAllocated then
begin
with SortCB do
begin
if not Assigned(SortProc) then lpfnCompare := @DefaultTreeViewSort
else lpfnCompare := SortProc;
hParent := TVI_ROOT;
lParam := Data;
Result := TreeView_SortChildrenCB(Handle, SortCB, 0);
end;
if Items.Count > 0 then
begin
Node := Items.GetFirstNode;
while Node <> nil do
begin
if Node.HasChildren then Node.CustomSort(SortProc, Data);
Node := Node.GetNext;
end;
end;
end;
end;
//Component Registration
procedure Register;
begin
RegisterComponents('Win32', [THETreeView]);
end;
end.