ContextGraphics draw image drawing nothing in Java

Question

I have two classes in my project. Main.java and Village.java. The class Main.java is supposed to pass a GraphicsContext object to Village.java so that it draws some image on the Application frame of Main.java. But it seems like my code has a bug because its not drawing anything..Here is my code...

//This is the main class and it extends Application class for drawing a frame object
public class Main extends Application{
//Define the main method
 public static void main(String args[]){
 //Draw the frame
 launch(args);
 
 }
 //This method override and passes a GraphicsContext object to a method in another class for drawing image
 @Override
 public void start(Stage stage) throws Exception {
 //Set the title of the application window
 stage.setTitle("Village");
 Group root= new Group();
 //Define a new canvas object
 Canvas newcanvas= new Canvas();
 //Get GraphicsContext object from the canvas
 GraphicsContext gc=newcanvas.getGraphicsContext2D();
 //Get an object of the class whose draw() method we wish to access
 Village myvillage=Village.create();
 //Call the method and pass GraphicsContext object as a parameter
 myvillage.draw(gc);
 root.getChildren().add(newcanvas);
 stage.setScene(new Scene(root));
 stage.show();
 }
}

Now the other class with target draw(GraphicsContext)method is this one..The image defined in there is in the same directory as these class files.

public class Village{
// Y co ordinate of where to draw the image
 static final double Y_VILLAGE=30;
 public void draw(GraphicsContext r){
 Image house=new Image("file:House.png",100,250,false,false);
 //Define the xPosition for this House object
 MyBuilding y=(MyBuilding)MyBuilding.create();
 //Use the GraphicsContext to draw on the Canvas, we get an X position on where to draw from user dialog
 //Draw the image
 r.drawImage(house, y.getXposition(), Village.Y_VILLAGE);
 
 }
}

Am getting the empty window below, please help meenter image description here

Answer 1

When looking through your code, I noticed that you are subject to a misunderstanding. In order to be able to draw on a canvas, you have to override the paint method and do your drawing operations there. I hope the hint helps you further.

• user10913773: Am gonna need more information on that, to which class is the method going? And whose interface is being overriden?
• user15314575: There are several ways to override the paint method in a Canvas. You could do this inline while creating your Canvas. You could write yourself a derivative of Canvas that overwrites paint. Your Village class could also be derived from Canvas, so that you can overwrite the paint method there. I don't know enough about your project to give you final advice. The documentation and the examples for Canvas are freely available online. Here at SO, too, there are a lot of questions and solutions about the Canvas class. Just have a look around there!