FMX解析BMP文件工厂

unit FMX.Canvas.D2D;

initialization
  TTextLayoutManager.RegisterTextLayout(TTextLayoutD2D, TCanvasD2D);

  TBitmapCodecManager.RegisterBitmapCodecClass(SBMPImageExtension, SVBitmaps, True, TBitmapCodecWIC);
  TBitmapCodecManager.RegisterBitmapCodecClass(SJPGImageExtension, SVJPGImages, True, TBitmapCodecWIC);
  TBitmapCodecManager.RegisterBitmapCodecClass(SJPEGImageExtension, SVJPGImages, True, TBitmapCodecWIC);
  TBitmapCodecManager.RegisterBitmapCodecClass(SPNGImageExtension, SVPNGImages, True, TBitmapCodecWIC);
  TBitmapCodecManager.RegisterBitmapCodecClass(SGIFImageExtension, SVGIFImages, True, TBitmapCodecWIC);
  TBitmapCodecManager.RegisterBitmapCodecClass(STIFImageExtension, SVTIFFImages, True, TBitmapCodecWIC);
  TBitmapCodecManager.RegisterBitmapCodecClass(STIFFImageExtension, SVTIFFImages, True, TBitmapCodecWIC);
  TBitmapCodecManager.RegisterBitmapCodecClass(SICOImageExtension, SVIcons, True, TBitmapCodecWIC);
  TBitmapCodecManager.RegisterBitmapCodecClass(SHDPImageExtension, SWMPImages, True, TBitmapCodecWIC);
end.

class procedure TBitmapCodecManager.RegisterBitmapCodecClass(const Extension, Description: string; const CanSave: Boolean;
  const BitmapCodecClass: TCustomBitmapCodecClass);
var
  LDescriptor: TBitmapCodecClassDescriptor;
begin
  if FBitmapCodecClassDescriptors = nil then
    FBitmapCodecClassDescriptors := TList<TBitmapCodecClassDescriptor>.Create;

  LDescriptor.Extension := Extension;
  LDescriptor.Description := Description;
  LDescriptor.BitmapCodecClass := BitmapCodecClass;
  LDescriptor.CanSave := CanSave;
  FBitmapCodecClassDescriptors.Add(LDescriptor);
end;

class function TBitmapCodecManager.LoadFromFile(const AFileName: string; const Bitmap: TBitmapSurface;
  const MaxSizeLimit: Cardinal = 0): Boolean;
var
  CodecClass: TCustomBitmapCodecClass;
  Codec: TCustomBitmapCodec;
begin
  CodecClass := FindBitmapCodecDescriptor(ExtractFileExt(AFileName),
    TBitmapCodecDescriptorField.Extension).BitmapCodecClass;
  if CodecClass <> nil then
  begin
    Codec := CodecClass.Create;
    try
      Result := Codec.LoadFromFile(AFileName, Bitmap, MaxSizeLimit);
    finally
      Codec.Free;
    end;
  end
  else
    Result := False;
end;

procedure TBitmap.LoadFromFile(const AFileName: string);
var
  Surf: TBitmapSurface;
begin
  Surf := TBitmapSurface.Create;
  try
    if TBitmapCodecManager.LoadFromFile(AFileName, Surf, CanvasClass.GetAttribute(TCanvasAttribute.MaxBitmapSize)) then
      Assign(Surf)
    else
      raise EBitmapLoadingFailed.CreateFMT(SBitmapLoadingFailedNamed, [AFileName]);
  finally
    Surf.Free;
  end;
end;