How to add images to TImageCollection programmatically

Question

I'm trying to load TImageCollection which I want to populate and save so it's available as a resource in a data module (.dfm file). This code adds images to the image collection from selected .png files and I can see the count increase, so it is populating

 ImageCollectionMS.Images.Add(ChangeFileExt(ShortName,''), Path+Shortname);`

but I need to save it as a resource. Can that be done?

Look at [`TStream.WriteComponent()`](http://docwiki.embarcadero.com/Libraries/en/System.Classes.TStream.WriteComponent) or [`TStream.WriteComponentRes()`](http://docwiki.embarcadero.com/Libraries/Rio/en/System.Classes.TStream.WriteComponentRes) for saving `TComponent`-derived objects to a stream in DFM format. — Remy Lebeau, Oct 07 '20 at 17:49
Are you writing a source code generator? A kind of compiler? Or maybe an IDE extension? If you explain what you want to achieve, maybe we can give a better answer? — fpiette, Oct 07 '20 at 18:51
I want to automate the building of a large ImageCollection, selecting .png files using specific programmed criteria rather than painstakingly adding them one by one trying to follow rules and not always succeeding. (Have had to write programs to organise my data for many years.) If the Image Collection Editor can do it programmatically I thought I could try. — Mike Scott, Oct 07 '20 at 19:08
@Mike-Scott not sure what's your case exactly, but if you want really "large ImageCollections" which needs to be filled by some rules - why not organize that at run time, store images in file system, define your rules in some kind of files (xml, ini, json, whatever). I dont understand why you need complex and large image collections in DFM. — Miroslav Penchev, Oct 08 '20 at 05:18

score 0 · Answer 1 · answered Oct 08 '20 at 11:03

This was how I did it:

Add to the ImageCollection, PNG file by PNG (using the preferred criteria):

ImageCollectionX.Add(ChangeFileExt(ShortName,''), FullFilename);

Then build dummy .DFM and .PAS files:

function PosInStr(const substr, str: String): integer;
var start, p : integer;
begin
  start := 1;
  Result := 0;
  repeat
    p := PosEx(Substr,Str,start);
    if p>0 then begin
      start := p+1;
      inc(Result);
    end;
  until P=0;
end;

procedure TForm1.WriteDFM(aStream: TStream; const ImgCollName, Suffix, Filename: string);
const DFMStart : array[0..14] of string =
  ('object Form%s: TForm%s',
  'Left = 0',
  'Top = 0',
  'Caption = ''Form%s''',
  'ClientHeight = 299',
  'ClientWidth = 635',
  'Color = clBtnFace',
  'Font.Charset = DEFAULT_CHARSET',
  'Font.Color = clWindowText',
  'Font.Height = -11',
  'Font.Name = ''Tahoma''',
  'Font.Style = []',
  'OldCreateOrder = False',
  'PixelsPerInch = 96',
  'TextHeight = 13');
var
  i, n : integer;
  outpfrm, outpImg : TStringlist;
  ConvStream: TStream;
begin
  aStream.Position := 0;
  outpFrm := TStringlist.Create;
  outpImg := TStringlist.Create;
  ConvStream := TMemoryStream.Create;
  try
    ObjectBinaryToText (aStream, ConvStream);
    ConvStream.Position := 0;
    outpImg.LoadFromStream(ConvStream);
    for i := Low(DFMStart) to High(DFMStart) do begin
      n := PosInStr('%s', DFMStart[i]);
      case n of 0:  outpFRM.Add(DFMStart[i]);
        1 : outpFRM.Add(Format(DFMStart[i],[suffix]));
        2 : outpFRM.Add(Format(DFMStart[i],[suffix, suffix]));
      end;
    end;
    outpFrm.AddStrings(outpImg);
    outpFrm.Add('end');
    outpFrm.SaveToFile(ChangeFileExt(Filename,'.dfm'));
    writePasForDFM(ImgCollName, Suffix, Filename);
  finally
    outpFrm.Free;
    outpImg.Free;
    ConvStream.Free
  end;
end;

procedure TForm1.WritePasForDFM(const ImgCollName, Suffix, Filename: string);
const
  PasStart : array[0..15] of string =
  ('unit %s;',
  'interface',
  'uses',
  'Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,',
  'Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.BaseImageCollection, Vcl.ImageCollection;',
  '',
  'type',
  'TForm%s = class(TForm)',
  '@: TImageCollection;',
  'end;',
  '',
  'var',
  'Form%s: TForm%s;',
  'implementation',
  '{$R *.dfm}',
  'end.');
var
  i, n: integer;
  outp : TStringlist;
begin
  outp := TStringlist.Create;
  try
    for i := Low(PASStart) to High(PASStart) do begin
      n := PosInStr('%s', PASStart[i]);
      case n of 0:
      if POs('@', PASStart[i])>0 then
        outp.Add(ImgCollName+ Copy(PASStart[i],2,maxint))
        else outp.Add(PASStart[i]);
        1 : outp.Add(Format(PasStart[i],[suffix]));
        2 : outp.Add(Format(PasStart[i],[suffix, suffix]));
      end;
    end;
    outp.SaveToFile(ChangeFileExt(Filename,'.pas'));
  finally
    outp.Free;
  end;
end;

How to add images to TImageCollection programmatically

1 Answers1