multitouch gesture issue

[udik]

1046: Type was not found or was not a compile-time constant:transformgestureevent

try to add swipe gesture to scroll_mc but receive error 1046 Type was not found or was not a compile-time constant:TransFormGestureEvent.

why?

package {

          import flash.desktop.NativeApplication;

          import flash.desktop.SystemIdleMode;

          import flash.display.MovieClip;

          import flash.media.Video;

          import flash.net.NetConnection;

          import flash.net.NetStream;

          import flash.events.MouseEvent;

          import flash.events.NetStatusEvent;

          import fl.controls.List

          import flash.events.Event;

                           import flash.ui.Multitouch;

          import flash.ui.MultitouchInputMode;

                    public class Main extends MovieClip {

                    public var song ["hatizmoret.flv","tarnegol.flv","se_ugdi.flv","dag.flv"]

                    public var song_number:String

                    .....

                   public var scroll_mc:MovieClip

                                      public function Main() {

                                      scroll_mc.addChild(A1)

  .........

             A1.x=posX

                                          A1.y=posY

             A1.height=high;

             A1.width=widt;

             A1.addEventListener(MouseEvent.CLICK, next_frame1);

.......

          scroll_mc.addEventListener (TransformGestureEvent.GESTURE_SWIPE, fl_SwipeHandler);

                              NativeApplication.nativeApplication.systemIdleMode = SystemIdleMode.KEEP_AWAKE;

                              netConnection = new NetConnection();

                              netConnection.connect(null);

                              netStream = new NetStream(netConnection);

                              netStream.client = this;

                              netStream.addEventListener(NetStatusEvent.NET_STATUS, statusUpdated);

                              video = new Video();

                              video.attachNetStream(netStream);

                              video.width = 480;

                              video.height = 320;

                              addChildAt(video, 0);

                    }

  ...............

                                                            setupControls();

                                                            trace(VIDEO_URL)

                                                            trace(song_number)

                                                  }

public function fl_SwipeHandler(event:TransformGestureEvent):void

{

          switch(event.offsetX)

          {

                    // swiped right

                    case 1:

                    {

                              scroll_mc.x += 20;

                              break;

                    }

                    case -1:

                    {

                              scroll_mc.x -= 20;

                              break;

                    }

          }

          switch(event.offsetY)

          {

                    case 1:

                    {

                              scroll_mc.y += 20;

                              break;

                    }

                    case -1:

                    {

                              scroll_mc.y -= 20;

                              break;

                    }

          }

}

                    public function hideBtns():void {

                              controls.visible = false;

                              blocker.visible = false;

                    }

                    public function showBtns(btns:Array):void {

                              controls.visible = true;

                              blocker.visible = true;

                              for(var instName:String in controls)

                              {

                                        if(btns.indexOf(instName) != -1)

                                        {

                                                  controls[instName].visible = true;

                                        }

                                        else

                                        {

                                                  controls[instName].visible = false;

                                        }

                              }

                    }

                                                  }

}

[kglad · Accepted solution]

import it:

import flash.events.TransformGestureEvent;