Delphi组件与属性编辑器

Delphi教程 2025-08-20

Delphi组件与属性编辑器

(一)前言

本文将用一个例子描述组件开发与属性编辑器。

例子(TdsWaitDialogEx)是一个可视组件,调用其show方法后显示一个Dialog,

其中包含一个TAnimate,两个提示信息(即TLabel),一个进度条(TGauge)。

枚举属性:DialogStyle,AViposition

记录属性:Options

属性集合对象从TPersistent继承,本文例中AVISource属性集合包含TAnimate

的动画属性CommonAVI、FileName

属性编辑器应用与AVISource的FileName属性,即String型FileName编辑时弹出一个

TOpenDialog,其过滤Filter为*.avi

(二)组件包dsDlgPack.dpk

为了便于发布、安装等,要用到要组件包.dpk。

在Delphi6以后的版本中(我不知D5以前的版本怎样),有若干文件Delphi没有发布,如PRoxies。

安装组件时若用到这些文件,可绕过这些文件而用包含这些文件的包。

本例属性编辑器用到DesignEditors文件,而DesignEditors中需要Proxies文件,因此在发布此组件

的包(.dpk)中包含designide,解决了Proxies不存在的问题,这样装组件就会成功

package dsDlgPack;

...

requires

rtl,

vcl,

VclSmp,

designide;

contains

dsDlgWaitEx in 'dsDlgWaitEx.pas' {DlgWaitEx},

dsDlgWaitExReg in 'dsDlgWaitExReg.pas';

end.

(三)组件注册文件dsDlgWaitExReg.pas

问:为什么要多用这样一个文件? 因为:

如果dsDlgWaitExReg.pas中的代码合并到dsDlgWaitEx.pas中,虽然dsDlgPack.dpk中包含designide

解决了安装组件时Proxies不存在的问题,但是在应用程序调用此组件时仍出Proxies不存在的问题,

因为DesignEditors中需要用到Proxies文件;因此象下面这段代码单独形成文件,应用程序调用此组

件是不需用到dsDlgWaitExReg.pas,可绕过Proxies不存在问题。

unit dsDlgWaitExReg;

interface

uses Classes, Dialogs, Forms, dsDlgWaitEx, DesignIntf, DesignEditors ;

type

TdsAVIFileNameProperty = class(TStringProperty) //属性编辑器要用到DesignEditors文件

public

function GetAttributes:TPropertyAttributes;override; //方法覆盖

procedure Edit;override; //方法覆盖

end;

procedure Register;

implementation

procedure Register;

begin

//注册此组件到 Delisoft 组件页面

RegisterComponents('Delisoft', [TdsWaitDialogEx]);

//注册此属性编辑器

RegisterPropertyEditor(TypeInfo(string), TdsAVISource, 'FileName', TdsAVIFileNameProperty);

end;

{ TdsAVIFileNameProperty }

function TdsAVIFileNameProperty.GetAttributes:TPropertyAttributes;

begin

result:=[paDialog];

end;

procedure TdsAVIFileNameProperty.Edit;

begin

with TOpenDialog.Create(application) do

try

Filter:='AVI Files(*.avi)|*.avi|All Files(*.*)|*.*';

if Execute then SetStrValue(FileName);

finally

free;

end;

end;

end.

(四)组件文件dsDlgWaitEx.pas

unit dsDlgWaitEx;

{定义本组件所有属性、方法;其中窗体TDlgWaitEx的属性BorderStyle为bsDialog,本例组件TdsDlgWaitEx用到窗体TDlgWaitEx;属性对象AVISource用到TdsAVISource,它是直接从TPersistent继承下来,另外用到枚举属性(DialogStyle、AVIPosition)和记录属性(Options)等。

}

interface

uses

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

Dialogs, StdCtrls, Gauges, ComCtrls;

type

TDialogStyle = (dlgNormal, dlgStayOnTop);

TAVIPosition = (aviLeft, aviTop, aviBottom);

TDlgOptions = set of (showAVI,showCaption,showMessage1,showMessage2,showProgress,ShowProgressText);

TDlgWaitEx = class(TForm)

Animate1: TAnimate;

Gauge1: TGauge;

Label1: TLabel;

Label2: TLabel;

procedure FormClose(Sender: TObject; var Action: TCloseAction);

private

FCloseAfter: DWord;

FUserFormClose: TCloseEvent;

public

property UserFormClose: TCloseEvent read FUserFormClose write FUserFormClose;

property CloseAfter: DWORD read FCloseAfter write FCloseAfter;

end;

TdsAVISource = class(TPersistent)

private

FCommonAVI: TCommonAVI;

FFileName: string;

procedure SetCommonAVI(const Value: TCommonAVI);

procedure SetFileName(const Value: string);

protected

public

published

property CommonAVI: TCommonAVI read FCommonAVI write SetCommonAVI default aviNone;

property FileName: string read FfileName write SetFileName ;

end;

TdsWaitDialogEx=class(TComponent)

private

//Form

FDlgForm:TDlgWaitEx;

FMessage1: string;

FMessage2: string;

FMessage1Font: TFont;

FMessage2Font: TFont;

FCaption: string;

FDislogStyle:TDialogStyle ;

FwordWrap:boolean;

FOptions:TDlgOptions;

FShowMessage1,FShowMessage2:boolean;

//AVI

FaviPosition: TAVIPosition ;

FAviActive:boolean;

FshowAVI:boolean;

FAVISource : TdsAVISource;

//progress

FProgressMax:integer;

FProgressMin:integer;

FProgressPos:integer;

FProgressStep:integer;

FShowProgress: Boolean;

FShowProgressText: Boolean;

//Event

FOnPosChange: TNotifyEvent;

FOnShow: TNotifyEvent;

FOnFormHide: TCloseEvent;

procedure SetProgressMax(const Value: integer);

procedure SetProgressMin(const Value: integer);

procedure SetProgressPos(const Value: integer);

procedure SetProgressStep(const Value: integer);

procedure DrawForm;

function setLableHeight(sCaption:string):integer;

procedure setOptions(const value:TDlgOptions);

procedure setMessage1(const value:string);

procedure setMessage2(const value:string);

procedure setCaption(const value:string);

procedure SetMessage1Font(const value:TFont);

procedure SetMessage2Font(const value:TFont);

function IsMessage1FontStored: Boolean;

function IsMessage2FontStored: Boolean;

procedure setAVIPosition(const Value: TAVIPosition);

procedure SetAVISource(const Value: TdsAVISource);

procedure SetOnFormHide(const Value: TCloseEvent);

protected

procedure DoPosChange; virtual;

procedure DoShow; virtual;

public

constructor Create(AOwner: TComponent); override;

destructor Destroy; override;

procedure FormShow;

procedure FormHide;

procedure FormUpdate;

procedure ProgressStepIt;

published

//Form

property Message1: string read FMessage1 write setMessage1 ;

property Message2: string read FMessage2 write setMessage2 ;

property Message1Font: TFont read FMessage1Font write SetMessage1Font stored IsMessage1FontStored;

property Message2Font: TFont read FMessage2Font write SetMessage2Font stored IsMessage2FontStored;

property Caption: string read FCaption write setCaption ;

property DislogStyle:TDialogStyle read FDislogStyle write FDislogStyle;

property wordWrap :boolean read FwordWrap write FwordWrap;

property Options:TDlgOptions read FOptions write setOptions;

//AVI

property AviActive: boolean read FAviActive write FAviActive ;

property AviPosition: TAVIPosition read FaviPosition write setAVIPosition ;

property AviSource: TdsAVISource read FAVISource write SetAVISource ;

//Progress

property ProgressMax: integer read FProgressMax write SetProgressMax ;

property ProgressMin: integer read FProgressMin write SetProgressMin ;

property ProgressPos: integer read FProgressPos write SetProgressPos ;

property ProgressStep:integer read FProgressStep write SetProgressStep;

//Event

property OnPosChange: TNotifyEvent read FOnPosChange write FOnPosChange;

property OnShow: TNotifyEvent read FOnShow write FOnShow;

property OnHide: TCloseEvent read FOnFormHide write SetOnFormHide;

end;

implementation

{$R *.DFM}

{ TdsAVISource }

procedure TdsAVISource.SetCommonAVI(const Value: TCommonAVI);

begin

if Value = FCommonAVI then exit;

FCommonAVI := Value;

FfileName:='';

end;

procedure TdsAVISource.SetFileName(const Value: string);

begin

if Value = FfileName then exit;

FfileName:=value;

FCommonAVI:=aviNone;

end;

{ TdsWaitDialogEx }

procedure TdsWaitDialogEx.DoShow;

begin

if Assigned(FOnShow) then FOnShow(Self);

end;

procedure TdsWaitDialogEx.DoPosChange;

begin

if Assigned(FOnPosChange) then FOnPosChange(Self);

end;

procedure TdsWaitDialogEx.SetAVISource(const Value: TdsAVISource);

begin

if FAVISource=value then exit;

FAVISource.Assign(Value);

if (FAVISource.FFileName='')and(FAVISource.FCommonAVI=aviNone) then FshowAVI:=false;

if assigned(FDlgForm) then

begin

FDlgForm.Animate1.Active:=false;

FDlgForm.Animate1.FileName := '';

FDlgForm.Animate1.CommonAVI := aviNone;

if FshowAVI then

begin

if FAVISource.FfileName='' then

FDlgForm.Animate1.CommonAVI := FAVISource.FCommonAVI

else

FDlgForm.Animate1.FileName := FAVISource.FfileName;

FDlgForm.Animate1.Active:=true;

end;

DrawForm; //Animate1- >AVI改变后,可能引起的Animate1大小改变 == > DrawForm

FDlgForm.Update;

end;

end;

function TdsWaitDialogEx.IsMessage1FontStored: Boolean;

begin

with FMessage1Font do

Result :=

(Name <  > 'MS Sans Serif') or

(Style <  > []) or

(Size <  > 8) or

(Color <  > clWindowText) or

(Charset <  > DEFAULT_CHARSET) or

(Pitch <  > fpDefault);

end;

function TdsWaitDialogEx.IsMessage2FontStored: Boolean;

begin

with FMessage2Font do

Result :=

(Name <  > 'MS Sans Serif') or

(Style <  > []) or

(Size <  > 8) or

(Color <  > clWindowText) or

(Charset <  > DEFAULT_CHARSET) or

(Pitch <  > fpDefault);

end;

procedure TdsWaitDialogEx.SetMessage1Font(const Value: TFont);

begin

FMessage1Font.Assign(Value);

if assigned(FDlgForm) then

begin

FDlgForm.Label1.Font.Assign(Value);

FDlgForm.Update;

end;

end;

procedure TdsWaitDialogEx.SetMessage2Font(const Value: TFont);

begin

FMessage2Font.Assign(Value);

if assigned(FDlgForm) then

begin

FDlgForm.Label2.Font.Assign(Value);

FDlgForm.Update ;

end;

end;

procedure TdsWaitDialogEx.setCaption(const value:string);

begin

if value=FCaption then exit ;

FCaption:=value;

if not (showCaption in FOptions) then

begin

FCaption:='';

exit;

end;

if assigned(FDlgForm) then

begin

FDlgForm.Caption := value;

FDlgForm.update;

end;

end;

procedure TdsWaitDialogEx.setMessage1(const value:string);

var i:integer;

begin

if value=FMessage1 then exit ;

FMessage1:=value;

if assigned(FDlgForm) then

begin

if not (showMessage1 in FOptions) then exit;

FDlgForm.Label1.Caption := value;

i:=setLableHeight(FMessage1)+13;

if i<  >FDlgForm.Label1.Height then DrawForm;

FDlgForm.update;

end;

end;

procedure TdsWaitDialogEx.setMessage2(const value:string);

var i:integer;

begin

if value=FMessage2 then exit ;

FMessage2:=value;

if assigned(FDlgForm) then

begin

if not (showMessage2 in FOptions) then exit;

FDlgForm.Label2.Caption := value;

i:=setLableHeight(FMessage2)+13;

if i<  >FDlgForm.Label2.Height then DrawForm;

FDlgForm.update;

end;

end;