Loading font from resource file

Question

I am having a Delphi XE Project with the following resource:

I have used function LoadResourceFont and tried the following code:

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

function LoadResourceFontByName( const ResourceName : string; ResType: PChar ) : Boolean;
var
  ResStream  : TResourceStream;
  FontsCount : DWORD;
begin
  ResStream := TResourceStream.Create(hInstance, ResourceName, ResType);
  try
    Result  := (AddFontMemResourceEx(ResStream.Memory, ResStream.Size, nil, @FontsCount) <> 0);
  finally
    ResStream.Free;
  end;
end;

function LoadResourceFontByID( ResourceID : Integer; ResType: PChar ) : Boolean;
var
  ResStream  : TResourceStream;
  FontsCount : DWORD;
begin
  ResStream := TResourceStream.CreateFromID(hInstance, ResourceID, ResType);
  try
    Result  := (AddFontMemResourceEx(ResStream.Memory, ResStream.Size, nil, @FontsCount) <> 0);
  finally
    ResStream.Free;
  end;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  if LoadResourceFontByName('MyFont1', RT_RCDATA) then Label1.Font.Name := 'My Custom Font1';
  if LoadResourceFontByID(2, RT_FONT) then Label2.Font.Name := 'My Custom Font2';   
end.

By the way: I know that I should have redistribution rights for the font if I need to embedded it into my EXE file.

But the problem is that if the font name ( I have used My Custom Font1, My Custom Font2) is not the actual name of the font, the font does not load properly and shows an unknown font character.

My question is that whether though I have used ResStream.Free in the founctions, yet I have to define again FormClose and FormDestroy event to protect Memory Leakage or not?

Answer 1

Your code has several errors in it.

1. LoadResourceFont() returns a Boolean. You are trying to assign that value to the TLabel.Font.Name property, which you cannot do since a Boolean is not a String. You are also trying to assign the Boolean to a TLabel.Font[2] property, which is not even a valid identifier to assign a value to.

2. Your first call to LoadResourceFont() is specifying the wrong resource name.

3. The first parameter of LoadResourceFont() is a String, but your second call to LoadResourceFont() is trying to pass the global Hinstance variable (an THandle) where a String is expected.

4. You are trying to load the second font as an RCDATA resource when it is actually a FONT resource instead.

To do what you are attempting, you need to call LoadResourceFont() first to load the font(s) into the font table, and then you can set the TLabel.Font.Name to the typeface name of the desired font (the name defined inside the TTF file, not the filename or resource name), eg:

function LoadResourceFontByName( const ResourceName : string; ResType: PChar ) : Boolean;
var
  ResStream : TResourceStream;
  FontsCount : DWORD;
begin
  ResStream := TResourceStream.Create(hInstance, ResourceName, ResType);
  try
    Result := (AddFontMemResourceEx(ResStream.Memory, ResStream.Size, nil, @FontsCount) <> 0);
  finally
    ResStream.Free;
  end;
end;

function LoadResourceFontByID( ResourceID : Integer; ResType: PChar ) : Boolean;
var
  ResStream : TResourceStream;
  FontsCount : DWORD;
begin
  ResStream := TResourceStream.CreateFromID(hInstance, ResourceID, ResType);
  try
    Result := (AddFontMemResourceEx(ResStream.Memory, ResStream.Size, nil, @FontsCount) <> 0);
  finally
    ResStream.Free;
  end;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  if LoadResourceFontByName('MyFont1', RT_RCDATA) then
    Label1.Font.Name := 'My Font Name 1';

  if LoadResourceFontByID(2, RT_FONT) then
    Label2.Font.Name := 'My Font Name 2';
end;

Answer 2

Label.Font doesn't have subscripts, so Label2.Font[2] is invalid.

Also, assigning the boolean result of your LoadFontResource function to a Label.Font of any kind will clearly not work, as that boolean result will never be a font.

I'd suggest you learn the basics of programming using Delphi and also study the VCL/FMX documentation for TFont before worrying about loading custom fonts from memory.