dbctrls.pas

这是不可多得的源代码

    property OnClick;
    property OnContextPopup;
    property OnDblClick;
    property OnDragDrop;
    property OnDragOver;
    property OnEndDock;
    property OnEndDrag;
    property OnEnter;
    property OnExit;
    property OnKeyDown;
    property OnKeyPress;
    property OnKeyUp;
    property OnMouseDown;
    property OnMouseMove;
    property OnMouseUp;
    property OnStartDock;
    property OnStartDrag;
  end;

const
  InitRepeatPause = 400;  { pause before repeat timer (ms) }
  RepeatPause     = 100;  { pause before hint window displays (ms)}
  SpaceSize       =  5;   { size of space between special buttons }

type
  TNavButton = class;
  TNavDataLink = class;

  TNavGlyph = (ngEnabled, ngDisabled);
  TNavigateBtn = (nbFirst, nbPrior, nbNext, nbLast,
                  nbInsert, nbDelete, nbEdit, nbPost, nbCancel, nbRefresh);
  TButtonSet = set of TNavigateBtn;
  TNavButtonStyle = set of (nsAllowTimer, nsFocusRect);

  ENavClick = procedure (Sender: TObject; Button: TNavigateBtn) of object;

{ TDBNavigator }

  TDBNavigator = class (TCustomPanel)
  private
    FDataLink: TNavDataLink;
    FVisibleButtons: TButtonSet;
    FHints: TStrings;
    FDefHints: TStrings;
    ButtonWidth: Integer;
    MinBtnSize: TPoint;
    FOnNavClick: ENavClick;
    FBeforeAction: ENavClick;
    FocusedButton: TNavigateBtn;
    FConfirmDelete: Boolean;
    FFlat: Boolean;
    procedure BtnMouseDown (Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
    procedure ClickHandler(Sender: TObject);
    function GetDataSource: TDataSource;
    function GetHints: TStrings;
    procedure HintsChanged(Sender: TObject);
    procedure InitButtons;
    procedure InitHints;
    procedure SetDataSource(Value: TDataSource);
    procedure SetFlat(Value: Boolean);
    procedure SetHints(Value: TStrings);
    procedure SetSize(var W: Integer; var H: Integer);
    procedure SetVisible(Value: TButtonSet);
    procedure WMSize(var Message: TWMSize);  message WM_SIZE;
    procedure WMSetFocus(var Message: TWMSetFocus); message WM_SETFOCUS;
    procedure WMKillFocus(var Message: TWMKillFocus); message WM_KILLFOCUS;
    procedure WMGetDlgCode(var Message: TWMGetDlgCode); message WM_GETDLGCODE;
    procedure CMEnabledChanged(var Message: TMessage); message CM_ENABLEDCHANGED;
    procedure WMWindowPosChanging(var Message: TWMWindowPosChanging); message WM_WINDOWPOSCHANGING;
  protected
    Buttons: array[TNavigateBtn] of TNavButton;
    procedure DataChanged;
    procedure EditingChanged;
    procedure ActiveChanged;
    procedure Loaded; override;
    procedure KeyDown(var Key: Word; Shift: TShiftState); override;
    procedure Notification(AComponent: TComponent;
      Operation: TOperation); override;
    procedure GetChildren(Proc: TGetChildProc; Root: TComponent); override;
    procedure CalcMinSize(var W, H: Integer);
  public
    constructor Create(AOwner: TComponent); override;
    destructor Destroy; override;
    procedure SetBounds(ALeft, ATop, AWidth, AHeight: Integer); override;
    procedure BtnClick(Index: TNavigateBtn); virtual;
  published
    property DataSource: TDataSource read GetDataSource write SetDataSource;
    property VisibleButtons: TButtonSet read FVisibleButtons write SetVisible
      default [nbFirst, nbPrior, nbNext, nbLast, nbInsert, nbDelete,
        nbEdit, nbPost, nbCancel, nbRefresh];
    property Align;
    property Anchors;
    property Constraints;
    property DragCursor;
    property DragKind;
    property DragMode;
    property Enabled;
    property Flat: Boolean read FFlat write SetFlat default False;
    property Ctl3D;
    property Hints: TStrings read GetHints write SetHints;
    property ParentCtl3D;
    property ParentShowHint;
    property PopupMenu;
    property ConfirmDelete: Boolean read FConfirmDelete write FConfirmDelete default True;
    property ShowHint;
    property TabOrder;
    property TabStop;
    property Visible;
    property BeforeAction: ENavClick read FBeforeAction write FBeforeAction;
    property OnClick: ENavClick read FOnNavClick write FOnNavClick;
    property OnContextPopup;
    property OnDblClick;
    property OnDragDrop;
    property OnDragOver;
    property OnEndDock;
    property OnEndDrag;
    property OnEnter;
    property OnExit;
    property OnResize;
    property OnStartDock;
    property OnStartDrag;
  end;

{ TNavButton }

  TNavButton = class(TSpeedButton)
  private
    FIndex: TNavigateBtn;
    FNavStyle: TNavButtonStyle;
    FRepeatTimer: TTimer;
    procedure TimerExpired(Sender: TObject);
  protected
    procedure Paint; override;
    procedure MouseDown(Button: TMouseButton; Shift: TShiftState;
      X, Y: Integer); override;
    procedure MouseUp(Button: TMouseButton; Shift: TShiftState;
      X, Y: Integer); override;
  public
    destructor Destroy; override;
    property NavStyle: TNavButtonStyle read FNavStyle write FNavStyle;
    property Index : TNavigateBtn read FIndex write FIndex;
  end;

{ TNavDataLink }

  TNavDataLink = class(TDataLink)
  private
    FNavigator: TDBNavigator;
  protected
    procedure EditingChanged; override;
    procedure DataSetChanged; override;
    procedure ActiveChanged; override;
  public
    constructor Create(ANav: TDBNavigator);
    destructor Destroy; override;
  end;

{ TDBLookupControl }

  TDBLookupControl = class;

  TDataSourceLink = class(TDataLink)
  private
    FDBLookupControl: TDBLookupControl;
  protected
    procedure FocusControl(Field: TFieldRef); override;
    procedure ActiveChanged; override;
    procedure LayoutChanged; override;
    procedure RecordChanged(Field: TField); override;
  public
    constructor Create;
  end;

  TListSourceLink = class(TDataLink)
  private
    FDBLookupControl: TDBLookupControl;
  protected
    procedure ActiveChanged; override;
    procedure DataSetChanged; override;
    procedure LayoutChanged; override;
  public
    constructor Create;
  end;

  TDBLookupControl = class(TCustomControl)
  private
    FLookupSource: TDataSource;
    FDataLink: TDataSourceLink;
    FListLink: TListSourceLink;
    FDataFieldName: string;
    FKeyFieldName: string;
    FListFieldName: string;
    FListFieldIndex: Integer;
    FDataField: TField;
    FMasterField: TField;
    FKeyField: TField;
    FListField: TField;
    FListFields: TList;
    FKeyValue: Variant;
    FSearchText: string;
    FLookupMode: Boolean;
    FListActive: Boolean;
    FHasFocus: Boolean;
    FNullValueKey: TShortCut;
    procedure CheckNotCircular;
    procedure CheckNotLookup;
    procedure DataLinkRecordChanged(Field: TField);
    function GetDataSource: TDataSource;
    function GetKeyFieldName: string;
    function GetListSource: TDataSource;
    function GetReadOnly: Boolean;
    procedure SetDataFieldName(const Value: string);
    procedure SetDataSource(Value: TDataSource);
    procedure SetKeyFieldName(const Value: string);
    procedure SetKeyValue(const Value: Variant);
    procedure SetListFieldName(const Value: string);
    procedure SetListSource(Value: TDataSource);
    procedure SetLookupMode(Value: Boolean);
    procedure SetReadOnly(Value: Boolean);
    procedure WMGetDlgCode(var Message: TMessage); message WM_GETDLGCODE;
    procedure WMKeyDown(var Message: TWMKeyDown); message WM_KEYDOWN;    
    procedure WMKillFocus(var Message: TMessage); message WM_KILLFOCUS;
    procedure WMSetFocus(var Message: TMessage); message WM_SETFOCUS;
    procedure CMEnabledChanged(var Message: TMessage); message CM_ENABLEDCHANGED;
    procedure CMGetDataLink(var Message: TMessage); message CM_GETDATALINK;
  protected
    function CanModify: Boolean; virtual;
    function GetBorderSize: Integer; virtual;
    function GetTextHeight: Integer; virtual;
    procedure KeyValueChanged; virtual;
    procedure ListLinkDataChanged; virtual;
    function LocateKey: Boolean; virtual;
    procedure Notification(AComponent: TComponent;
      Operation: TOperation); override;
    procedure ProcessSearchKey(Key: Char); virtual;
    procedure SelectKeyValue(const Value: Variant); virtual;
    procedure UpdateDataFields; virtual;
    procedure UpdateListFields; virtual;
    property DataField: string read FDataFieldName write SetDataFieldName;
    property DataLink: TDataSourceLink read FDataLink;
    property DataSource: TDataSource read GetDataSource write SetDataSource;
    property HasFocus: Boolean read FHasFocus;
    property KeyField: string read GetKeyFieldName write SetKeyFieldName;
    property KeyValue: Variant read FKeyValue write SetKeyValue;
    property ListActive: Boolean read FListActive;
    property ListField: string read FListFieldName write SetListFieldName;
    property ListFieldIndex: Integer read FListFieldIndex write FListFieldIndex default 0;
    property ListFields: TList read FListFields;
    property ListLink: TListSourceLink read FListLink;
    property ListSource: TDataSource read GetListSource write SetListSource;
    property NullValueKey: TShortCut read FNullValueKey write FNullValueKey default 0;    
    property ParentColor default False;
    property ReadOnly: Boolean read GetReadOnly write SetReadOnly default False;
    property SearchText: string read FSearchText write FSearchText;
    property TabStop default True;
  public
    constructor Create(AOwner: TComponent); override;
    destructor Destroy; override;
    function ExecuteAction(Action: TBasicAction): Boolean; override;
    function UpdateAction(Action: TBasicAction): Boolean; override;
    property Field: TField read FDataField;
  end;

{ TDBLookupListBox }

  TDBLookupListBox = class(TDBLookupControl)
  private
    FRecordIndex: Integer;
    FRecordCount: Integer;
    FRowCount: Integer;
    FBorderStyle: TBorderStyle;
    FPopup: Boolean;
    FKeySelected: Boolean;
    FTracking: Boolean;
    FTimerActive: Boolean;
    FLockPosition: Boolean;
    FMousePos: Integer;
    FSelectedItem: string;
    function GetKeyIndex: Integer;
    procedure SelectCurrent;
    procedure SelectItemAt(X, Y: Integer);
    procedure SetBorderStyle(Value: TBorderStyle);
    procedure SetRowCount(Value: Integer);
    procedure StopTimer;
    procedure StopTracking;
    procedure TimerScroll;
    procedure UpdateScrollBar;
    procedure CMCtl3DChanged(var Message: TMessage); message CM_CTL3DCHANGED;
    procedure CMFontChanged(var Message: TMessage); message CM_FONTCHANGED;
    procedure WMCancelMode(var Message: TMessage); message WM_CANCELMODE;
    procedure WMTimer(var Message: TMessage); message WM_TIMER;
    procedure WMVScroll(var Message: TWMVScroll); message WM_VSCROLL;
  protected
    procedure CreateParams(var Params: TCreateParams); override;
    procedure CreateWnd; override;
    procedure KeyDown(var Key: Word; Shift: TShiftState); override;
    procedure KeyPress(var Key: Char); override;
    procedure KeyValueChanged; override;
    procedure ListLinkDataChanged; override;
    procedure MouseDown(Button: TMouseButton; Shift: TShiftState;
      X, Y: Integer); override;
    procedure MouseMove(Shift: TShiftState; X, Y: Integer); override;
    procedure MouseUp(Button: TMouseButton; Shift: TShiftState;
      X, Y: Integer); override;
    procedure Paint; override;
    procedure UpdateListFields; override;
  public
    constructor Create(AOwner: TComponent); override;
    function ExecuteAction(Action: TBasicAction): Boolean; override;
    function UpdateAction(Action: TBasicAction): Boolean; override;
    function UseRightToLeftAlignment: Boolean; override;
    property KeyValue;
    property SelectedItem: string read FSelectedItem;
    procedure SetBounds(ALeft, ATop, AWidth, AHeight: Integer); override;
  published
    property Align;
    property Anchors;
    property BevelEdges;
    property BevelInner;
    property BevelOuter;
    property BevelKind;
    property BevelWidth;
    property BiDiMode;
    property BorderStyle: TBorderStyle read FBorderStyle write SetBorderStyle default bsSingle;
    property Color;
    property Constraints;
    property Ctl3D;
    property DataField;
    property DataSource;
    property DragCursor;
    property DragKind;
    property DragMode;
    property Enabled;
    property Font;
    property ImeMode;
    property ImeName;
    property KeyField;
    property ListField;
    property ListFieldIndex;
    property ListSource;
    property NullValueKey;
    property ParentBiDiMode;
    property ParentColor;
    property ParentCtl3D;
    property ParentFont;
    property ParentShowHint;
    property PopupMenu;
    property ReadOnly;
    property RowCount: Integer read FRowCount write SetRowCount stored False;
    property ShowHint;
    property TabOrder;
    property TabStop;
    property Visible;
    property OnClick;
    property OnContextPopup;
    property OnDblClick;
    property OnDragDrop;
    property OnDragOver;
    property OnEndDock;
    property OnEndDrag;
    property OnEnter;
    property OnExit;
    property OnKeyDown;
    property OnKeyPress;
    property OnKeyUp;
    property OnMouseDown;
    property OnMouseMove;
    property OnMouseUp;
    property OnStartDock;
    property OnStartDrag;
  end;

{ TDBLookupComboBox }

  TPopupDataList = class(TDBLookupListBox)
  private
    procedure WMMouseActivate(var Message: TMessage); message WM_MOUSEACTIVATE;
  protected
    procedure CreateParams(var Params: TCreateParams); override;
  public
    constructor Create(AOwner: TComponent); override;
  end;

  TDropDownAlign = (daLeft, daRight, daCenter);

  TDBLookupComboBox = class(TDBLookupControl)
  private
    FDataList: TPopupDataList;
    FButtonWidth: Integer;
    FText: string;
    FDropDownRows: Integer;
    FDropDownWidth: Integer;
    FDropDownAlign: TDropDownAlign;
    FListVisible: Boolean;
    FPressed: Boolean;
    FTracking: Boolean;
    FAlignment: TAlignment;
    FLookupMode: Boolean;
    FMouseInControl: Boolean;
    FOnDropDown: TNotifyEvent;
    FOnCloseUp: TNotifyEvent;
    procedure ListMouseUp(Sender: TObject; Button: TMouseButton;