unit trans;
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs;
implementation
type
TSetLayeredWindowAttributes =
function (
hwnd : HWND;
// handle to the layered window
crKey : TColor;
// specifies the color key
bAlpha : byte;
// value for the blend function
dwFlags : DWORD
// action
): BOOL;
stdcall;
const
WS_EX_LAYERED = $80000;
LWA_COLORKEY = 1;
LWA_ALPHA = 2;
procedure MakeTransparent(AHandle : THandle; AValue : byte = 0);
var
Info: TOSVersionInfo;
SetLayeredWindowAttributes: TSetLayeredWindowAttributes;
begin
//Check Windows version
Info.dwOSVersionInfoSize := SizeOf(Info);
GetVersionEx(Info);
if (Info.dwPlatformId = VER_PLATFORM_WIN32_NT)
and
(Info.dwMajorVersion >= 5)
then
begin
SetLayeredWindowAttributes := GetProcAddress(GetModulehandle(user32),'
SetLayeredWindowAttributes');
if Assigned(SetLayeredWindowAttributes)
then
begin
SetWindowLong(AHandle, GWL_EXSTYLE, GetWindowLong(AHandle, GWL_EXSTYLE)
or WS_EX_LAYERED);
//Make form transparent
SetLayeredWindowAttributes(AHandle, 0, AValue, LWA_ALPHA);
end;
end;
end;
end.