AS3: runtime font loading (embedding)

Flash still can't load directly a font file. That's why I embeded the font in a swf that had to be loaded later. In my case it was better to create different swf file for every font, but if you prefer you can put all the fonts in only one file. So create a new flash document and open the library panel (press F11). Click on the little button in the top right corner.[1]and choose New Font.... [2]Fill the Character ranges part, choose your font and remember the value of the Family field. After that move to the second tab ActionScript. [3]Check Export for ActionScript and Export in frame 1. Type a class name of the font (you will need this name later). Everything is ready and you can compile the swf that will be used. The following code loads the produced swf file and adds a text field, which uses the font.

package {
    import flash.display.Loader;
    import flash.display.MovieClip;
    import flash.events.Event;
    import flash.events.IOErrorEvent;
    import flash.net.URLRequest;
    import flash.text.Font;
    import flash.text.TextField;
    import flash.text.TextFieldAutoSize;
    import flash.text.TextFormat;
    public class App extends MovieClip {
      public static
      const FONT_NAME: String = "Brush Script Std";
      public static
      const FONT_EXPORT_NAME: String = "FontBrushScript";
      public static
      const FONT_FILE_NAME: String = "font/BrushScript.swf";
  
      function App(): void {
        var loader: Loader = new Loader();
        loader.contentLoaderInfo.addEventListener(Event.COMPLETE, onFontLoaded);
        loader.addEventListener(IOErrorEvent.IO_ERROR, onFontLoadingFailed);
        loader.addEventListener(IOErrorEvent.NETWORK_ERROR, onFontLoadingFailed);
        loader.addEventListener(IOErrorEvent.VERIFY_ERROR, onFontLoadingFailed);
        loader.addEventListener(IOErrorEvent.DISK_ERROR, onFontLoadingFailed);
        loader.load(new URLRequest(FONT_FILE_NAME));
      }
      private
      function onFontLoaded(e: Event): void {
        trace("Successfully loaded " + FONT_EXPORT_NAME + " (" + FONT_FILE_NAME + ")");
        if (e.target.applicationDomain.hasDefinition(FONT_EXPORT_NAME)) {
          var FontClass: Class = e.target.applicationDomain.getDefinition(FONT_EXPORT_NAME) as Class;
          Font.registerFont(FontClass);
          addTextField();
        } else {
          trace("Missing " + FONT_EXPORT_NAME + "!");
        }
      }
      private
      function onFontLoadingFailed(e: IOErrorEvent): void {
        trace("Missing " + FONT_FILE_NAME);
      }
      private
      function addTextField(): void {
        trace("Adding text field ...");
        var format: TextFormat = new TextFormat();
        format.font = FONT_NAME;
        format.size = 45;
        format.color = 0x9f0000;
        format.bold = true;
        var field: TextField = new TextField();
        field.defaultTextFormat = format;
        field.text = "Embed font at runtime.";
        field.x = field.y = 35;
        field.embedFonts = true;
        field.autoSize = TextFieldAutoSize.LEFT;
        addChild(field);
      }
    }
  }

There are three major constants in the code:

public static
    const FONT_NAME: String = "Brush Script Std";
    public static
    const FONT_EXPORT_NAME: String = "FontBrushScript";
    public static
    const FONT_FILE_NAME: String = "font/BrushScript.swf";

The first one FONT_NAME is used in the TextFormat definition. You should use the real family name of the font. The second one is the name of the class that you have to fill. And the last one is just the path to the swf file. You can download the full example's code here.