import javafx.application.Application;
import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.layout.StackPane;

import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
import javafx.scene.paint.Color;

public class FrameCanvas extends Application{
  public static void main(String[] args){
    launch(args);
  }
  @Override
  public void start(Stage primaryStage)throws Exception{
    ////////////////////Basic FX stuff
    Canvas theCanvas = new Canvas(900,900);
    StackPane theLayout = new StackPane();
    theLayout.getChildren().add(theCanvas);
    Scene theScene = new Scene(theLayout,900,900);
    primaryStage.setScene(theScene);
    primaryStage.show();
    ///////////////////////
    /////Drawing an X
    ///////////////////////
    GraphicsContext gc = theCanvas.getGraphicsContext2D();
    Thread.sleep(1000);
    gc.strokeLine(0,0,200,200);
    Thread.sleep(1000);
    gc.strokeLine(200,0,0,200);
    /////////////////////////////
  }
}