酒杯上的碟

上去.

我前面说过,(交叉平台控件)会有一些不同,但是这只会影响那些依赖于Windows API写控件的开发者.如果你写的控件是从VCL继承的,是聚合(aggregate)了一些控件的(就像我在TCalculator里面做的),是一个非可视的不依赖于Windows API的,或者是一个TGraphic控件,那么转移到Linux下不会遇到什么麻烦.

这篇文章介绍的软件产品的功能正在开发中,并且会在没有通知的情况下有些变化.相应功能的描述是应时而变的,并且没有任何确定的服务承诺.

做为Delphi最初测试版的用户,Robert Kozak从1999年下半年加入Borland的Kylix R&D小组.从他加入Borland开始,他就和C++Builder 5和Kylix的开发密切相关.Robert还和TaDDA(多伦多区Delphi开发者协会)有关,这个协会后来和TDUG(多伦多区Delphi用户组)合并.Robert在这些用户社团一直很活跃,同时也经常出现在Borland的新闻组里面.

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QCalc.pas

{ ***************************************************** }
{ }
{ Borland Delphi Visual Component Library }
{ Borland Delphi Component Library (X)Crossplatform }
{ }
{ Copyright (c) 2000 Inprise/Borland }
{ }
{ ***************************************************** }

unit QCalc;

// This is the very first Custom control written for CLX.

interface

uses
Sysutils, Classes, QT, QControls, QStdCtrls, QComCtrls,
QGraphics;

type
TButtonType = (bt0, bt1, bt2, bt3, bt4, bt5, bt6, bt7,
bt8, bt9, btDecimal, btPlusMinus, btMultiply, btDivide,
btAdd, btSubtract, btSqrt, btPercent, btInverse,
btEquals, btBackspace, btClear, btClearAll,
btMemoryRecall, btMemoryStore, btMemoryClear,
btMemoryAdd);

TCalcState = (csNone, csAdd, csSubtract, csMultiply, csDivide);

TButtonRecord = record
Top: Integer;
Left: Integer;
Width: Integer;
Height: Integer;
Caption: string;
Color: TColor;
end;

TCalculator = class(TFrameControl)
private
FResultEdit: TEdit;

FStatus: TLabel;
FMemoryValue: Single;
FCurrentValue: Single;
FLastValue: Single;
FRepeatValue: Single;
FState: TCalcState;
FBackSpaceValid: Boolean;
protected
Btns: array [TButtonType] of TButtonRecord;
procedure BuildCalc;
procedure Calc(Sender: TObject);
function GetText : string; override;
procedure SetText(const Value : string); override;
public
constructor Create(AOwner: TComponent); override;
property Value : Single read FCurrentValue;
published
property Text : string read GetText write SetText;
property BorderStyle;
property LineWidth;
property Margin;
property MidLineWidth;
property FrameRect;
end;

implementation

function ButtonRecord(aTop, aLeft, aWidth, aHeight: Integer; aCaption: string;
aColor: TColor = clBtnFace): TButtonRecord; 《酒杯上的碟(第4页)》