Inno Setup - How to display localized RTF text in custom page

Question

How to use this code to show the same text, with the same structure (fonts, etc) but in different languages? For example: English and Spanish in a language selector.

Answer 1

For the caption and description of the custom page, define custom messages in the language files, the same way as in Inno Setup - How to localize component and type names?

[CustomMessages]
ISCustomPage1_Caption=Some caption
ISCustomPage1_Description=Some description

And then use these custom messages using the CustomMessage function function in your code.

For the RTF text, the best solution is to create separate .rtf files and load an appropriate one based on the selected language.

[Languages]
Name: "eng"; MessagesFile: "Idiomas\English.isl"
Name: "spa"; MessagesFile: "Idiomas\Spanish.isl"

[Files]
Source: "eng.rtf"; Flags: dontcopy
Source: "spa.rtf"; Flags: dontcopy

[Code]

var
  ISCustomPage1: TWizardPage;
  RichEditViewer1: TRichEditViewer;

procedure InitializeWizard;
var
  RtfName: string;
  Rtf: AnsiString;
begin
  { Creates custom wizard page }
  ISCustomPage1 :=
    CreateCustomPage(
      wpWelcome, CustomMessage('ISCustomPage1_Caption'),
      CustomMessage('ISCustomPage1_Description'));

  { RichEditViewer1 }
  RichEditViewer1 := TRichEditViewer.Create(WizardForm);
  with RichEditViewer1 do
  begin
    Parent := ISCustomPage1.Surface;
    Left := ScaleX(0);
    Top := ScaleY(0);
    Width := ScaleX(417);
    Height := ScaleY(241);
    ReadOnly := True;
    ScrollBars := ssVertical;

    RtfName := ActiveLanguage + '.rtf';
    ExtractTemporaryFile(RtfName);
    if LoadStringFromFile(ExpandConstant('{tmp}\' + RtfName), Rtf) then
    begin
      UseRichEdit := True;
      RTFText  := Rtf;
    end;
  end;
end;