4

から写真を撮ってTImageListに入れるTImage(または として返すTGraphic) にはどうすればよいですか?

重要な点は、aTImageListには 32 bpp のアルファ ブレンド画像を含めることができるということです。目標は、これらのアルファ ブレンド画像の 1 つを取得し、TImage. これは、ある時点でTGraphic. ただし、厳密に言えば、私の質問はImageListからImageに画像を配置することです。それが中間者なしで達成できれば、それTGraphicも問題ありません。

私達何が欲しいの？

関数の内臓が必要です。

procedure GetImageListImageIntoImage(SourceImageList: TCustomImageList; 
      ImageIndex: Integer; TargetImage: TImage);
begin
   //TODO: Figure this out.
   //Neither SourceImageList.GetIcon nor SourceImageList.GetBitmap preserve the alpha channel
end;

別の便利な中間ヘルパー関数もあります。

function ImageListGetGraphic(ImageList: TCustomImageList; ImageIndex: Integer): TGraphic;
var
//  ico: TIcon;
    bmp: TBitmap;
begin
    {Doesn't work; loses alpha channel. 
    Windows Icon format can support 32bpp alpha bitmaps. But it just doesn't work here
    ico := TIcon.Create;
    ImageList.GetIcon(ImageIndex, ico, dsTransparent, itImage);
    Result := ico;
    }

    {Doesn't work; loses alpha channel.
    Windows does support 32bpp alpha bitmaps. But it just doesn't work here
    bmp := TBitmap.Create;
    bmp.PixelFormat := pf32bit;
    Imagelist.GetBitmap(ImageIndex, bmp);
    Result := bmp;
    }
end;

元の手順を次のように変換します。

procedure GetImageListImageIntoImage(SourceImageList: TCustomImageList; ImageIndex: Integer; TargetImage: TImage);
var
   g: TGraphic;
begin
   g := ImageListGetGraphic(SourceImageList, ImageIndex);
   TargetImage.Picture.Graphic := g; //Assignment of TGraphic does a copy
   g.Free;
end;

私もいくつかのランダムなもの：

Image1.Picture := TPicture(ImageList1.Components[0]);

しかし、それはコンパイルされません。

PS私はDelphi 2010を持っています

4

2 に答える 2

2 
ImageList1.GetBitmap(0, Image1.Picture.Bitmap);
于 2012-06-10T22:59:09.113 に答える
0

Routine to get a transparent graphic out of an ImageList:

function ImageListGetGraphic(ImageList: TCustomImageList; ImageIndex: Integer): TGraphic;
var
    ico: HICON;
//  png: TPngImage;
//  icon: TIcon;
//  bmp: TBitmap;
    wicbmp: IWICBitmap;
    wi: TWicImage;
begin
{   //Works. Uses our own better Wic library.
    ico := ImageList_GetIcon(ImageList.Handle, ImageIndex, ILD_NORMAL);
    Result := TWicGraphic.FromHICON(ico);
    DestroyIcon(ico);}

    //Works, uses the built-in Delphi TWicImage (careful of VCL bugs)
    ico := ImageList_GetIcon(ImageList.Handle, ImageIndex, ILD_NORMAL);
    wi := TWICImage.Create; //Due to a bug in the VCL, you must construct the TWicImage before trying to access the Wic ImagingFactory
    OleCheck(TWicImage.ImagingFactory.CreateBitmapFromHICON(ico, wicbmp));
    wi.Handle := wicbmp;
    Result := wi;

{   //Doesn't work, loses alpha channel
    icon := TIcon.Create;
    ImageList.GetIcon(ImageIndex, icon, dsTransparent, itImage);
    Result := icon;
    }

{   //Doesn't work, loses alpha channel
    bmp := TBitmap.Create;
    bmp.PixelFormat := pf32bit;
    Imagelist.GetBitmap(ImageIndex, bmp);
    Result := bmp;
    }

{   //Fails: cannot assign a TIcon to a TPngImage
    icon := TIcon.Create;
    ImageList.GetIcon(ImageIndex, icon, ImgList.dsNormal, itImage);
    png := TPngImage.Create;
    png.Assign(icon);
    Result := png;
    icon.Free;
    }

{   //Working failure; doesn't support stretched drawing (e.g. TImage.Stretch = true)
    icon := TIcon.Create;
    ImageList.GetIcon(ImageIndex, icon, ImgList.dsNormal, itImage);
    Result := ico;
    }

end;

Sample usage:

g: TGraphic;

g := ImageListGetGraphic(ImageList1, 7);
Image1.Picture.Graphic := g;
g.Free;

Note: Any code released into public domain. No attribution required.

于 2014-10-14T17:38:00.807 に答える