[JAVA3D] Can not find a canvas3D method

[Tiziana]

Why i get this error msg? The method is in the Api reference so i could use it. java/prova3> javac J3dSwingFrame.java J3dSwingFrame.java:397: Method isOffScreen() not found in class javax.media.j3d.Canvas3D. if(canvas.isOffScreen()) System.out.println("Si"); 1 error java/prova3> Thank you TizianaCimoli