一個能罷放控件的statusbar (2001年3月2日) 

網友更新  分類:數據庫   作者:George  推薦:GeorgeAPI   閱讀次數:355  
(http://www.codesky.net)  

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unit ggeProgressBar;

interface

uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
ComCtrls,dbctrls,db;

type
TggeProgressBar = class(TProgressBar)
private
{ Private declarations }
FDataLink:TFieldDataLink;
function GetDataField:String;
procedure SetDataField(Value:String);
function GetDataSource:TDatasource;
procedure SetDataSource(Value:TDatasource);
function GetField:TField;
protected
{ Protected declarations }
//data link event handle
procedure DataChange(Sender:TObject);
public
{ Public declarations }
Constructor Create(AOwner:TComponent);override;
destructor Destroy;override;
property Field:TField read GetField;
published
{ Published declarations }
property DataField:String read GetDataField write SetDataField;
property DataSource:TDataSource read GetDatasource write SetDataSource;
end;

procedure Register;

implementation

procedure Register;
begin
RegisterComponents('win32', [TggeProgressBar]);
end;

{ TggeProgressBar }

constructor TggeProgressBar.Create(AOwner: TComponent);
begin
inherited create(AOwner);
FDatalink:=TFieldDatalink.Create;
FDatalink.control:=self;
FDatalink.OnDatachange:=DataChange;
end;

procedure TggeProgressBar.DataChange(Sender: TObject);
begin
if (FDatalink.Field<>nil) and (FDataLink.Field is TNumericField) then
position:=FDatalink.Field.AsInteger
else
position:=Min;
end;

destructor TggeProgressBar.Destroy;
begin
FDatalink.Free;
FDatalink:=nil;
inherited Destroy;
end;

function TggeProgressBar.GetDataField: String;
begin
Result:=FDataLink.FieldName;
end;

function TggeProgressBar.GetDataSource: TDatasource;
begin
Result:=FDatalink.Datasource;
end;

function TggeProgressBar.GetField: TField;
begin
Result:=FDataLink.Field;
end;

procedure TggeProgressBar.SetDataField(Value: String);
begin
FDataLink.FieldName:=Value;
end;

procedure TggeProgressBar.SetDataSource(Value: TDatasource);
begin
FDatalink.Datasource:=Value;
end;

end.