Edit с возможностью автоматического выбора

Содержание материала

...маленький компонент THintEdit, порожденный от TCustomEdit, который представляет собой с виду обычный TEdit элемент с возможностью автоматического выбора стринговых значений из скрытого списка (так, как это реализовано в Netscape Navigator'е). Описание особенно не нужно, так как выполнено все достаточно элементарно: значения для выбора заносятся в свойство HintList, тип свойства TStrings. При нажатии клавиш вверх/вниз выбираются значения, соответствующие набранным начальным символам.

Code:

unit HintEdit;

interface

uses

Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,

StdCtrls;

type

THintEdit = class(TCustomEdit)

private

{ Private declarations }

FHintList: TStrings;

Searching,

CanSearch: boolean;

CurSPos: integer;

protected

{ Protected declarations }

procedure Change; override;

procedure KeyDown(var Key: Word; Shift: TShiftState); override;

public

{ Public declarations }

constructor Create(AOwner: TComponent); override;

property HintList: TStrings read FHintList write FHintList;

destructor Destroy; override;

published

{ Published declarations }

property Anchors;

property AutoSelect;

property AutoSize;

property BiDiMode;

property BorderStyle;

property CharCase;

property Color;

property Constraints;

property Ctl3D;

property DragCursor;

property DragKind;

property DragMode;

property Enabled;

property Font;

property HideSelection;

property ImeMode;

property ImeName;

property MaxLength;

property OEMConvert;

property ParentBiDiMode;

property ParentColor;

property ParentCtl3D;

property ParentFont;

property ParentShowHint;

property PasswordChar;

property PopupMenu;

property ReadOnly;

property ShowHint;

property TabOrder;

property TabStop;

property Text;

property Visible;

property OnChange;

property OnClick;

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;

procedure Register;

implementation

{$R *.DCR}

procedure Register;

begin

RegisterComponents('Netscape', [THintEdit]);

end;

constructor THintEdit.Create;

begin

inherited;

FHintList := TStringList.Create;

Searching := false;

CanSearch := true;

CurSPos := -1;

end;

procedure THintEdit.Change;

var

i, l: integer;

begin

if Searching then

Exit;

if not CanSearch then

Exit;

if Text = '' then

exit;

l := Length(Text);

for i := 0 to FHintList.Count - 1 do

if Copy(FHintList[i], 1, l) = Text then

begin

Searching := true;

CurSPos := i;

Text := FHintList[i];

Searching := false;

SelStart := Length(Text);

SelLength := -(Length(Text) - l);

break;

end;

inherited;

end;

procedure THintEdit.KeyDown;

var

l: integer;

begin

if Chr(Key) in ['A'..'z', 'А'..'Я', 'а'..'я'] then

CanSearch := true

else

CanSearch := false;

case Key of

VK_DOWN:

begin

if (CurSPos < HintList.Count - 1) and (SelLength > 0) then

if Copy(FHintList[CurSPos + 1], 1, SelStart) = Copy(Text, 1, SelStart)

then

begin

l := SelStart;

Inc(CurSPos);

Text := FHintList[CurSPos];

SelStart := Length(Text);

SelLength := -(Length(Text) - l);

end;

Key := VK_RETURN;

end;

VK_UP:

begin

if (CurSPos > 0) and (SelLength > 0) then

if Copy(FHintList[CurSPos - 1], 1, SelStart) = Copy(Text, 1, SelStart)

then

begin

l := SelStart;

Dec(CurSPos);

Text := FHintList[CurSPos];

SelStart := Length(Text);

SelLength := -(Length(Text) - l);

end;

Key := VK_RETURN;

end;

VK_RETURN:

begin

SelStart := 0;

SelLength := Length(Text);

end;

inherited;

end;

destructor THintEdit.Destroy;

begin

FHintList.Free;

inherited;

end;

Подстановка в TEdit

Code:

var

words: TStringList;

procedure TForm1.FormCreate(Sender: TObject);

begin

words := TStringList.Create;

words.Sorted := true;

words.Add('one');

words.Add('two');

words.Add('four');

words.Add('five');

words.Add('six');

words.Add('seven');

words.Add('eight');

words.Add('nine');

words.Add('ten');

end;

procedure TForm1.Edit1KeyUp(Sender: TObject; var Key: Word;

Shift: TShiftState);

const

chars: set of char = ['A'..'Z', 'a'..'z', 'А'..'Я', 'а'..'я'];

var

w: string;

i: integer;

s: string;

full: string;

SelSt: integer;

begin

case Key of

VK_RETURN, VK_TAB:

begin

Edit1.SelStart := Edit1.SelStart + Edit1.SelLength;

Edit1.SelLength := 0;

Exit;

end;

VK_DELETE, VK_BACK:

begin

Edit1.ClearSelection;

Exit;

end;

s := Edit1.Text;

SelSt := Edit1.SelStart;

i := SelSt;

if (length(s) > i) and (s[i+1] in chars) then

Exit;

w := '';

while (i >= 1) and (s[i] in chars) do

begin

w := s[i] + w;

dec(i);

end;

if length(w) <= 0 then

Exit;

words.Find(w, i);

if (i >= 0) and (UpperCase(copy(words[i], 1,

length(w))) = UpperCase(w)) then

begin

full := words[i];

insert(copy(full, length(w) + 1, length(full)), s, SelSt + 1);

Edit1.Text := s;

Edit1.SelStart := SelSt;

Edit1.SelLength := length(full) - length(w);

end;

TEdit, TSpinEdit