DeWeb : 制作图片轮换效果

演示：http://www.web0000.com/slide.dw

源代码：http://www.web0000.com/media/source/slide.zip

一、新建一个DLL
二、除第一行外，更改源码为

uses
  ShareMem,  SysUtils,  Forms,  Messages,  StdCtrls,
  Variants,  Windows,  Classes,
  unit1 in 'unit1.pas' {Form1};

{$R *.res}
type
  PdwGetEvent=function (ACtrl:TComponent;AData:String):string; StdCall;
var
  DLLApp    : TApplication;
  DLLScreen : TScreen;
function dwLoad(AParams:String;AApp:TApplication;AScreen:TScreen):TForm;stdcall;
var
     AForm     : TForm1;
begin
     //
     Application    := AApp;
     Screen         := AScreen;
     AForm          := TForm1.Create(nil);
     AForm.Hint     := AParams;
     Result         := AForm;
end;

procedure DLLUnloadProc(dwReason: DWORD);
begin
     if dwReason = DLL_PROCESS_DETACH then begin
          Application    := DLLApp; //恢复
          Screen         := DLLScreen;
     end;
end;

exports
     dwLoad;

begin
     DLLApp    := Application; //保存 DLL 中初始的 Application
     DLLScreen := Screen;
     DLLProc   := @DLLUnloadProc;//保证卸载时恢复原Application
     DLLUnloadProc(DLL_PROCESS_DETACH);
end.

三、新建一个Form,保存为unit1.pas. 窗体名称为Form1
四、在合适位置旋转1个TImage、1个TTimer和3个TButton
五、在TTimer的OnTimer事件中写入

procedure TForm1.Timer_SlideTimer(Sender: TObject);
begin
     //set tag
     if Timer_Slide.Tag<3 then begin
          Timer_Slide.Tag     := Timer_Slide.Tag + 1;
     end else begin
          Timer_Slide.Tag     := 1;
     end;
     //change the image src
     Image_MN.Hint  := '{"src":"/media/images/mn/'+IntToStr(Timer_Slide.Tag)+'.jpg"}';
end;

六、3个按钮的Caption分别为1，2，3，
设置OnEnter事件代码为

procedure TForm1.Button1Enter(Sender: TObject);
begin
     //Stop the slide timer
     Timer_Slide.DesignInfo   := 0;
     //set tag
     Timer_Slide.Tag          := StrToIntDef(TButton(Sender).Caption,1);
     //change the image src
     Image_MN.Hint  := '{"src":"/media/images/mn/'+IntToStr(Timer_Slide.Tag)+'.jpg"}';

end;

设置OnExit事件代码为

procedure TForm1.Button1Exit(Sender: TObject);
begin
     //start the slide timer
     Timer_Slide.DesignInfo   := 1;

end;

这样基本上就可以了。