关于制作类似FOXMAIL的启动封面的问题。(30分)

FOXMAIL4.0有一个启动封面，如果在Win2000或Win XP里运行时它就会渐渐程透明消失。
同时在D6中我也知道可以使用AlphaBlendValue这个属性来设置窗体的半透明效果。
启动封面我也会做。
但是效果不如FOXMAIL4.0的。
不知道应该如何做才做到像FOXMAIL4.0的效果呢？
最好有源码！

关注 。

分太少的话还可以商量！

好象是一个第三方窗体容器的控件，你找一找了。

分是少了一点，但是我还是想要
在
FormCloseQuery事件里加入下面的代码就可以实现，其实在以前的帖子里介绍过的
AnimateWindow(Handle,400,AW_BLEND);

AnimateWindow能在win2000或Nt中用吗？我找找看。。。

这是我自己写的：
procedure TFormsplash.FormActivate(Sender: TObject);
begin
Formsplash.Update;
Formsplash.AlphaBlendValue:=100;
while Formsplash.AlphaBlendValue<253 do //要是255的话，值会溢出
Formsplash.AlphaBlendValue:=Formsplash.AlphaBlendValue+3;
Sleep(500);

end;

不过效果和FoxMail的还是有点差别，
不知道他的具体的值AlphaBlendValue是怎样改变的。

这个很容易做，不过要做好，和DELPLHI的一样确实不太容易呀，
如果图片大了，开始的时候可以看见窗口的颜色，不好做的和VC
做的一样，不知道其他兄弟们有什么好办法？[]

我找到这个好东东了
{============================================================
= FadeWindow =
= =
= =
= 版本：1.0beta =
= 功能：支持在Win2k下自动实现窗口淡入淡出效果 =
= 作者：Flier (Flier@stu.ccnu.edu.cn) =
= 日期：2000年8月5日 =
= 版权：你可以在任意商业或非商业程序中使用本控件 =
= 但是在传播此控件时请不要删去以上说明 =
============================================================}
unit FadeWindow;

interface

uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, ExtCtrls;

type
TFadeWindow = class(TComponent)
private
OldWndProc: TFarProc;
NewWndProc: Pointer;

CanHide: Boolean;
FadeAlpha: Integer;
FadeTimer: TTimer;

FFadeWin: TForm;

FEnabled: Boolean;
FFadeTime: Integer;

FFadeShow: Boolean;
FFadeHide: Boolean;

FMinAlpha: Byte;
FMaxAlpha: Byte;
FFadeStep: Byte;

FOnFadeShowComplete: TNotifyEvent;

procedure HookParent;
procedure UnhookParent;

procedure HookWndProc(var Message: TMessage);

procedure SetMinAlpha(Value: Byte);
procedure SetMaxAlpha(Value: Byte);

procedure InitWnd;
procedure DoneWnd;
procedure SetWndAlpha(const Alpha: Byte);

procedure OnFadeShow(Sender: TObject);
procedure OnFadeHide(Sender: TObject);
protected
public
destructor Destroy; override;
constructor Create(AOwner: TComponent); override;
published
property Enabled: Boolean read FEnabled write FEnabled default True;
property FadeTime: Integer read FFadeTime write FFadeTime default 1000;

property FadeWin: TForm read FFadeWin write FFadeWin;

property FadeShow: Boolean read FFadeShow write FFadeShow default True;
property FadeHide: Boolean read FFadeHide write FFadeHide default True;

property MinAlpha: Byte read FMinAlpha write SetMinAlpha default Low(Byte);
property MaxAlpha: Byte read FMaxAlpha write SetMaxAlpha default High(Byte);
property FadeStep: Byte read FFadeStep write FFadeStep default 5;

property OnFadeShowComplete: TNotifyEvent read FOnFadeShowComplete write FOnFadeShowComplete;
end;

procedure Register;

implementation

const
MinAlpha = 0;
MaxAlpha = High(Byte);

const
user32 = 'user32.dll';

WS_EX_LAYERED = $00080000;

LWA_COLORKEY = $00000001;
LWA_ALPHA = $00000002;

function SetLayeredWindowAttributes(hWnd: HWND;
crKey: TColorRef;
bAlpha: Byte;
dwFlags: DWord): BOOL; stdcall;
external user32
name 'SetLayeredWindowAttributes';


{ TFadeWindow }
constructor TFadeWindow.Create(AOwner: TComponent);
begin
inherited Create(AOwner);

OldWndProc := nil;
NewWndProc := nil;

CanHide := False;

FadeTimer := TTimer.Create(nil);
FadeTimer.Enabled := False;

if Owner is TForm then
FFadeWin := Owner as TForm
else
FFadeWin := nil;

FEnabled := True;
FFadeTime := 1000;

FFadeShow := True;
FFadeHide := True;

FMinAlpha := Low(Byte);
FMaxAlpha := High(Byte);
FFadeStep := 5;

FOnFadeShowComplete := nil;

if not (csDesigning in ComponentState) then
HookParent;
end;

destructor TFadeWindow.Destroy;
begin
//if not (csDesigning in ComponentState) then
// UnhookParent;

FadeTimer.Free;

inherited Destroy;
end;

procedure TFadeWindow.SetMinAlpha(Value: Byte);
begin
if Value <= MaxAlpha then
begin
FMinAlpha := Value;
end
else
begin
FMinAlpha := FMaxAlpha;
FMaxAlpha := Value;
end;
end;

procedure TFadeWindow.SetMaxAlpha(Value: Byte);
begin
if Value >= MinAlpha then
begin
FMaxAlpha := Value;
end
else
begin
FMaxAlpha := FMinAlpha;
FMinAlpha := Value;
end;
end;

procedure TFadeWindow.HookParent;
begin
if Assigned(FFadeWin) and IsWindow(FFadeWin.Handle) then
begin
OldWndProc := TFarProc(GetWindowLong(FFadeWin.Handle, GWL_WNDPROC));
NewWndProc := MakeObjectInstance(HookWndProc);
SetWindowLong(FFadeWin.Handle, GWL_WNDPROC, LongInt(NewWndProc));
end;
end;

procedure TFadeWindow.UnhookParent;
begin
if Assigned(FFadeWin) and IsWindow(FFadeWin.Handle) and Assigned(OldWndProc) then
SetWindowLong(FFadeWin.Handle, GWL_WNDPROC, LongInt(OldWndProc));

if Assigned(NewWndProc) then
FreeObjectInstance(NewWndProc);

NewWndProc := nil;
OldWndProc := nil;
end;

procedure TFadeWindow.InitWnd;
var
l: Longint;
begin
l := GetWindowLong(FFadeWin.Handle, GWL_EXSTYLE);
l := l or WS_EX_LAYERED;
SetWindowLong(FFadeWin.Handle, GWL_EXSTYLE, l);
end;

procedure TFadeWindow.DoneWnd;
var
l: Longint;
begin
l := GetWindowLong(FFadeWin.Handle, GWL_EXSTYLE);
l := l and (not WS_EX_LAYERED);
SetWindowLong(FFadeWin.Handle, GWL_EXSTYLE, l);
end;

procedure TFadeWindow.SetWndAlpha(const Alpha: Byte);
begin
SetLayeredWindowAttributes(FFadeWin.Handle,
0,
Alpha,
LWA_ALPHA);
end;

procedure TFadeWindow.OnFadeShow(Sender: TObject);
begin
SetWndAlpha(FadeAlpha);
Inc(FadeAlpha, FFadeStep);
if FadeAlpha >= FMaxAlpha then
begin
(Sender as TTimer).Enabled := False;
if FadeAlpha <> FMaxAlpha then
SetWndAlpha(FMaxAlpha);
//DoneWnd;
if Assigned(FOnFadeShowComplete) then
FOnFadeShowComplete(Self);
end;
end;

procedure TFadeWindow.OnFadeHide(Sender: TObject);
begin
SetWndAlpha(FadeAlpha);
Dec(FadeAlpha, FFadeStep);
if FadeAlpha <= FMinAlpha then
begin
(Sender as TTimer).Enabled := False;
CanHide := True;
(FFadeWin as TForm).Close;
end;
end;

procedure TFadeWindow.HookWndProc(var Message: TMessage);
procedure DefaultHandler;
begin
with Message do
Result := CallWindowProc(OldWndProc, FFadeWin.Handle, Msg, wParam, lParam);
end;
begin
if FEnabled and Assigned(FFadeWin) and IsWindow(FFadeWin.Handle) then
begin
FadeTimer.Interval := FFadeTime div ((FMaxAlpha - FMinAlpha + 1) div FFadeStep);

case Message.Msg of
WM_SHOWWINDOW:
if TWMShowWindow(Message).Show then
begin
if FFadeShow then
begin
InitWnd;
FadeAlpha := FMinAlpha;
SetWndAlpha(FadeAlpha);
end;

DefaultHandler;

if FFadeShow then
begin
FadeTimer.OnTimer := OnFadeShow;
FadeTimer.Enabled := True;
end;
end
else
DefaultHandler;
WM_CLOSE:
begin
if FFadeHide then
begin
if CanHide then
begin
(FFadeWin as TForm).Visible := False;
DoneWnd;
UnhookParent;
DefaultHandler;
CanHide := False;
end
else
begin
//InitWnd;

FadeAlpha := FMaxAlpha;
SetWndAlpha(FadeAlpha);

FadeTimer.OnTimer := OnFadeHide;
FadeTimer.Enabled := True;
end;
end;
end;
else
DefaultHandler;
end
end
else
DefaultHandler;
end;

procedure Register;
begin
RegisterComponents('Flier', [TFadeWindow]);
end;

end.

心情好，人人有分！