virtualtrees.pas

Last change: 2008-02-03 This is the source code of KCeasy。

unit VirtualTrees;

// Version 4.4.3
//
// The contents of this file are subject to the Mozilla Public License
// Version 1.1 (the "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at http://www.mozilla.org/MPL/
//
// Alternatively, you may redistribute this library, use and/or modify it under the terms of the
// GNU Lesser General Public License as published by the Free Software Foundation;
// either version 2.1 of the License, or (at your option) any later version.
// You may obtain a copy of the LGPL at http://www.gnu.org/copyleft/.
//
// Software distributed under the License is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the
// specific language governing rights and limitations under the License.
//
// The original code is VirtualTrees.pas, released September 30, 2000.
//
// The initial developer of the original code is digital publishing AG (Munich, Germany, www.digitalpublishing.de),
// written by Mike Lischke ([e-mail], www.soft-gems.net).
//
// Portions created by digital publishing AG are Copyright
// (C) 1999-2001 digital publishing AG. All Rights Reserved.
//----------------------------------------------------------------------------------------------------------------------
//
// December 2005
//   - Bug fix: check for column index for auto setting main column if the current one is deleted.
//
// For full document history see help file.
//
// Credits for their valuable assistance and code donations go to:
//   Freddy Ertl, Marian Aldenh鰒el, Thomas Bogenrieder, Jim Kuenemann, Werner Lehmann, Jens Treichler,
//   Paul Gallagher (IBO tree), Ondrej Kelle, Ronaldo Melo Ferraz, Heri Bender, Roland Bed黵ftig (BCB)
//   Anthony Mills, Alexander Egorushkin (BCB), Mathias Torell (BCB), Frank van den Bergh, Vadim Sedulin, Peter Evans,
//   Milan Vandrovec (BCB), Steve Moss, Joe White, David Clark, Anders Thomsen, Igor Afanasyev, Eugene Programmer,
//   Corbin Dunn, Richard Pringle, Uli Gerhardt, Azza, Igor Savkic
// Beta testers:
//   Freddy Ertl, Hans-J黵gen Schnorrenberg, Werner Lehmann, Jim Kueneman, Vadim Sedulin, Moritz Franckenstein,
//   Wim van der Vegt, Franc v/d Westelaken
// Indirect contribution (via publicly accessible work of those persons):
//   Alex Denissov, Hiroyuki Hori (MMXAsm expert)
// Documentation:
//   Markus Spoettl and toolsfactory GbR (http://www.doc-o-matic.com/, sponsoring Soft Gems development
//   with a free copy of the Doc-O-Matic help authoring system), Sven H. (Step by step tutorial)
// CLX:
//   Dmitri Dmitrienko (initial developer)
//----------------------------------------------------------------------------------------------------------------------

interface

{$booleval off} // Use fastest possible boolean evaluation.

{$I Compilers.inc}
{$I VTConfig.inc}

{$ifdef COMPILER_7_UP}
  // For some things to work we need code, which is classified as being unsafe for .NET.
  {$warn UNSAFE_TYPE off}
  {$warn UNSAFE_CAST off}
  {$warn UNSAFE_CODE off}
{$endif COMPILER_7_UP}

{$HPPEMIT '#include <objidl.h>'}
{$HPPEMIT '#include <oleidl.h>'} // Necessary for BCB 6 SP 2.

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, ImgList, ActiveX, StdCtrls, Menus, Printers,
  CommCtrl  // image lists, common controls tree structures
  {$ifdef ThemeSupport}
    {$ifndef COMPILER_7_UP}
      , ThemeSrv, TMSchema, UxTheme  // Windows XP themes support. Get these units from www.soft-gems.net
    {$else}
      , Themes, UxTheme
    {$endif COMPILE_7_UP}
  {$endif ThemeSupport}
  {$ifdef TntSupport}
    , TntStdCtrls       // Unicode aware inplace editor.
  {$endif TntSupport}
  ;

const
  VTVersion = '4.4.3';
  VTTreeStreamVersion = 2;
  VTHeaderStreamVersion = 3;    // The header needs an own stream version to indicate changes only relevant to the header.

  CacheThreshold = 2000;        // Number of nodes a tree must at least have to start caching and at the same
                                // time the maximum number of nodes between two cache entries.
  FadeAnimationStepCount = 255; // Number of animation steps for hint fading (0..255).
  ShadowSize = 5;               // Size in pixels of the hint shadow. This value has no influence on Win2K and XP systems
                                // as those OSes have native shadow support.

  // Special identifiers for columns.
  NoColumn = -1;
  InvalidColumn = -2;

  // Indices for check state images used for checking.
  ckEmpty                  =  0;  // an empty image used as place holder
  // radio buttons
  ckRadioUncheckedNormal   =  1;
  ckRadioUncheckedHot      =  2;
  ckRadioUncheckedPressed  =  3;
  ckRadioUncheckedDisabled =  4;
  ckRadioCheckedNormal     =  5;
  ckRadioCheckedHot        =  6;
  ckRadioCheckedPressed    =  7;
  ckRadioCheckedDisabled   =  8;
  // check boxes
  ckCheckUncheckedNormal   =  9;
  ckCheckUncheckedHot      = 10;
  ckCheckUncheckedPressed  = 11;
  ckCheckUncheckedDisabled = 12;
  ckCheckCheckedNormal     = 13;
  ckCheckCheckedHot        = 14;
  ckCheckCheckedPressed    = 15;
  ckCheckCheckedDisabled   = 16;
  ckCheckMixedNormal       = 17;
  ckCheckMixedHot          = 18;
  ckCheckMixedPressed      = 19;
  ckCheckMixedDisabled     = 20;
  // simple button
  ckButtonNormal           = 21;
  ckButtonHot              = 22;
  ckButtonPressed          = 23;
  ckButtonDisabled         = 24;

  // Instead using a TTimer class for each of the various events I use Windows timers with messages
  // as this is more economical.
  ExpandTimer = 1;
  EditTimer = 2;
  HeaderTimer = 3;
  ScrollTimer = 4;
  ChangeTimer = 5;
  StructureChangeTimer = 6;
  SearchTimer = 7;

  // Need to use this message to release the edit link interface asynchronously.
  WM_CHANGESTATE = WM_APP + 32;

  // Virtual Treeview does not need to be subclassed by an eventual Theme Manager instance as it handles
  // Windows XP theme painting itself. Hence the special message is used to prevent subclassing.
  CM_DENYSUBCLASSING = CM_BASE + 2000;

  // Decoupling message for auto-adjusting the internal edit window.
  CM_AUTOADJUST = CM_BASE + 2005;

  // VT's own clipboard formats,
  // Note: The reference format is used internally to allow to link to a tree reference
  //       to implement optimized moves and other back references.
  CFSTR_VIRTUALTREE = 'Virtual Tree Data';
  CFSTR_VTREFERENCE = 'Virtual Tree Reference';
  CFSTR_HTML = 'HTML Format';
  CFSTR_RTF = 'Rich Text Format';
  CFSTR_RTFNOOBJS = 'Rich Text Format Without Objects';
  CFSTR_CSV = 'CSV';

  // Drag image helpers for Windows 2000 and up.
  IID_IDropTargetHelper: TGUID = (D1: $4657278B; D2: $411B; D3: $11D2; D4: ($83, $9A, $00, $C0, $4F, $D9, $18, $D0));
  IID_IDragSourceHelper: TGUID = (D1: $DE5BF786; D2: $477A; D3: $11D2; D4: ($83, $9D, $00, $C0, $4F, $D9, $18, $D0));
  IID_IDropTarget: TGUID = (D1: $00000122; D2: $0000; D3: $0000; D4: ($C0, $00, $00, $00, $00, $00, $00, $46));
  CLSID_DragDropHelper: TGUID = (D1: $4657278A; D2: $411B; D3: $11D2; D4: ($83, $9A, $00, $C0, $4F, $D9, $18, $D0));

  SID_IDropTargetHelper = '{4657278B-411B-11D2-839A-00C04FD918D0}';
  SID_IDragSourceHelper = '{DE5BF786-477A-11D2-839D-00C04FD918D0}';
  SID_IDropTarget = '{00000122-0000-0000-C000-000000000046}';

  // Help identifiers for exceptions. Application developers are responsible to link them with actual help topics.
  hcTFEditLinkIsNil      = 2000;
  hcTFWrongMoveError     = 2001;
  hcTFWrongStreamFormat  = 2002;
  hcTFWrongStreamVersion = 2003;
  hcTFStreamTooSmall     = 2004;
  hcTFCorruptStream1     = 2005;
  hcTFCorruptStream2     = 2006;
  hcTFClipboardFailed    = 2007;
  hcTFCannotSetUserData  = 2008;

  // Header standard split cursor.
  crHeaderSplit = TCursor(100);

  UtilityImageSize = 16; // Needed by descendants for hittests.
  
var // Clipboard format IDs used in OLE drag'n drop and clipboard transfers.
  CF_VIRTUALTREE,
  CF_VTREFERENCE,
  CF_VRTF,
  CF_VRTFNOOBJS,   // Unfortunately CF_RTF* is already defined as being
                   // registration strings so I have to use different identifiers.
  CF_HTML,
  CF_CSV: Word;

  MMXAvailable: Boolean; // necessary to know because the blend code uses MMX instructions

  IsWinNT: Boolean;      // Necessary to fix bugs in Win95/WinME (non-client area region intersection, edit resize)
                         // and to allow for check of system dependent hint animation.
  IsWin2K: Boolean;      // Nessary to provide correct string shortage
  IsWinXP: Boolean;

  {$MinEnumSize 1, make enumerations as small as possible}

type
  // The exception used by the trees.
  EVirtualTreeError = class(Exception);

  PCardinal = ^Cardinal;

  // Limits the speed interval which can be used for auto scrolling (milliseconds).
  TAutoScrollInterval = 1..1000;

  // Need to declare the correct WMNCPaint record as the VCL (D5-) doesn't.
  TRealWMNCPaint = packed record
    Msg: Cardinal;
    Rgn: HRGN;
    lParam: Integer;
    Result: Integer;
  end;

  // The next two message records are not declared in Delphi 6 and lower.
  TWMPrint = packed record
    Msg: Cardinal;
    DC: HDC;
    Flags: Cardinal;
    Result: Integer;
  end;

  TWMPrintClient = TWMPrint;

  {$ifndef COMPILER_5_UP}
    TWMContextMenu = TWMMouse;
  {$endif COMPILER_5_UP}

  // Be careful when adding new states as this might change the size of the type which in turn
  // changes the alignment in the node record as well as the stream chunks.
  // Do not reorder the states and always add new states at the end of this enumeration in order to avoid
  // breaking existing code. 
  TVirtualNodeState = (
    vsInitialized,       // Set after the node has been initialized.
    vsChecking,          // Node's check state is changing, avoid propagation.
    vsCutOrCopy,         // Node is selected as cut or copy and paste source.
    vsDisabled,          // Set if node is disabled.
    vsDeleting,          // Set when the node is about to be freed.
    vsExpanded,          // Set if the node is expanded.
    vsHasChildren,       // Indicates the presence of child nodes without actually setting them.
    vsVisible,           // Indicate whether the node is visible or not (independant of the expand states of its parents).
    vsSelected,          // Set if the node is in the current selection.
    vsInitialUserData,   // Set if (via AddChild or InsertNode) initial user data has been set which requires OnFreeNode.
    vsAllChildrenHidden, // Set if vsHasChildren is set and no child node has the vsVisible flag set.
    vsClearing,          // A node's children are being deleted. Don't register structure change event.
    vsMultiline,         // Node text is wrapped at the cell boundaries instead of being shorted.
    vsHeightMeasured,    // Node height has been determined and does not need a recalculation.
    vsToggling           // Set when a node is expanded/collapsed to prevent recursive calls.
  );
  TVirtualNodeStates = set of TVirtualNodeState;

  // States used in InitNode to indicate states a node shall initially have.
  TVirtualNodeInitState = ( 
    ivsDisabled,
    ivsExpanded,