Delphi Haven: Loading the app’s icon into a TImage on Windows

Last time I showed how to load the icon of an FMX for Android app into a TImage. In practice, a lot of the debugging of a Delphi mobile app is likely to be with a Win32 ‘mobile preview’ build though… in which case it would be useful to load the icon when running on Windows as well.

To do that, you need to first add a *.ico version to the project. This is done via Project Options: select the Application item on the left, then All configurations – 32 bit Windows platform from the combo box at the top. Probably stating the obvious, but the icon loaded here should be a .ico version of the .png files set up for Android.

Once done, the most direct equivalent of the Android code I presented previously would be to use the LoadIcon Windows API to load the icon, then GetIconInfo and so forth to get the bitmap bits to copy to a FMX bitmap. Easier is to use the VCL however – since Vcl.Graphics.pas doesn’t bring in anything else of the VCL, there’s little point in deliberately avoiding it. As such, here’s an expanded version of the code I presented last time with a VCL-based Windows implementation added:

unit AppIconLoader;

interface

uses
  System.SysUtils, System.Classes, FMX.Graphics;

function GetAppIcon(Dest: TBitmap): Boolean;

implementation

uses
  {$IF DEFINED(ANDROID)}
  AndroidApi.JniBridge, AndroidApi.Jni.App, AndroidApi.Jni.GraphicsContentViewText, FMX.Helpers.Android,
  {$ELSEIF DEFINED(MSWINDOWS)}
  Vcl.Graphics,
  {$ENDIF}
  FMX.Surfaces;

function GetAppIcon(Dest: FMX.Graphics.TBitmap): Boolean;
{$IF DEFINED(ANDROID)}
var
  Activity: JActivity;
  Drawable: JDrawable;
  Bitmap: JBitmap;
  Surface: TBitmapSurface;
begin
  Result := False;
  Activity := SharedActivity;
  Drawable := Activity.getPackageManager.getApplicationIcon(Activity.getApplicationInfo);
  Bitmap := TJBitmapDrawable.Wrap((Drawable as ILocalObject).GetObjectID).getBitmap;
  Surface := TBitmapSurface.Create;
  try
    if not JBitmapToSurface(Bitmap, Surface) then
      Exit;
    Dest.Assign(Surface);
  finally
    Surface.Free;
  end;
  Result := True;
end;
{$ELSEIF DEFINED(MSWINDOWS)}
var
  Icon: TIcon;
  Stream: TMemoryStream;
begin
  Result := False;
  Stream := nil;
  Icon := TIcon.Create;
  try
    Icon.LoadFromResourceName(HInstance, 'MAINICON');
    if Icon.Handle = 0 then Exit;
    Stream := TMemoryStream.Create;
    Icon.SaveToStream(Stream);
    Stream.Position := 0;
    Dest.LoadFromStream(Stream);
  finally
    Icon.Free;
    Stream.Free;
  end;
  Result := True;
end;
{$ELSE}
begin
  Result := False;
end;
{$ENDIF}

end.