Delphi编程 -- How do I create an icon from a bitmap?

Question and Answer Database

FAQ2748D.txt How do I create an icon from a bitmap?

Category :Windows API

Platform :All

Product :All 32 bit

Question:

How do I create an icon from an bitmap?

Answer:

You must create two bitmaps, a mask bitmap (called the "AND"

bitmap) and a image bitmap (called the XOR bitmap). You can pass the

handles to the "AND" and "XOR" bitmaps to the Windows API function

CreateIconIndirect() and use the returned icon handle in your

application.

Example:

procedure TForm1.Button1Click(Sender: TObject);

var

IconSizeX : integer;

IconSizeY : integer;

AndMask : TBitmap;

XOrMask : TBitmap;

IconInfo : TIconInfo;

Icon : TIcon;

begin

{Get the icon size}

IconSizeX := GetSystemMetrics(SM_CXICON);

IconSizeY := GetSystemMetrics(SM_CYICON);

{Create the "And" mask}

AndMask := TBitmap.Create;

AndMask.Monochrome := true;

AndMask.Width := IconSizeX;

AndMask.Height := IconSizeY;

{Draw on the "And" mask}

AndMask.Canvas.Brush.Color := clWhite;

AndMask.Canvas.FillRect(Rect(0, 0, IconSizeX, IconSizeY));

AndMask.Canvas.Brush.Color := clBlack;

AndMask.Canvas.Ellipse(4, 4, IconSizeX - 4, IconSizeY - 4);

{Draw as a test}

Form1.Canvas.Draw(IconSizeX * 2, IconSizeY, AndMask);

{Create the "XOr" mask}

XOrMask := TBitmap.Create;

XOrMask.Width := IconSizeX;

XOrMask.Height := IconSizeY;

{Draw on the "XOr" mask}

XOrMask.Canvas.Brush.Color := ClBlack;

XOrMask.Canvas.FillRect(Rect(0, 0, IconSizeX, IconSizeY));

XOrMask.Canvas.Pen.Color := clRed;

XOrMask.Canvas.Brush.Color := clRed;

XOrMask.Canvas.Ellipse(4, 4, IconSizeX - 4, IconSizeY - 4);

{Draw as a test}

Form1.Canvas.Draw(IconSizeX * 4, IconSizeY, XOrMask);

{Create a icon}

Icon := TIcon.Create;

IconInfo.fIcon := true;

IconInfo.xHotspot := 0;

IconInfo.yHotspot := 0;

IconInfo.hbmMask := AndMask.Handle;

IconInfo.hbmColor := XOrMask.Handle;

Icon.Handle := CreateIconIndirect(IconInfo);

{Destroy the temporary bitmaps}

AndMask.Free;

XOrMask.Free;

{Draw as a test}

Form1.Canvas.Draw(IconSizeX * 6, IconSizeY, Icon);

{Assign the application icon}

Application.Icon := Icon;

{Force a repaint}

InvalidateRect(Application.Handle, nil, true);

{Free the icon}

Icon.Free;

end;

7/16/98 4:31:28 PM