<identifier expected> error. please help!

[christopherx]

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class gfxUser
{
JFrame f = new JFrame();
GraphicsObj g = new GraphicsObj();
f.add(g); // Error is here.

I'm using BlueJ, and i'm a complete newby
with it, but I have alot of background in c# and VB, so I'm not a total idiot! :D I just wondered where this error is coming from, can you help please guyys? Thankyou!

[Fubarable]

You're trying to call methods outside of a method or constructor. Perhaps you want to do this in the class's constructor?

[christopherx]

I guess I should have been more explicit with the code. The GraphicsObj extends a JPanel, so in theory it should just be like
adding a JPanel too a Frame? The problem is that isn't working for me!

[Fubarable]

I guess I should have been more explicit with the code. The GraphicsObj extends a JPanel, so in theory it should just be like adding a JPanel too a Frame? The problem is that isn't working for me!

That has no bearing on the problem. Again, you're trying to make method calls outside of a constructor or method. Again, you must make these calls inside of a constructor or method. Please let me know if you don't understand this as it is a fundamental concept in Java.

[christopherx]

Ah. In that case please tell me what you mean by Methods and constructors. Thankyou! :)

[Fubarable]

Ah. In that case please tell me what you mean by Methods and constructors. Thankyou! :)

What text or tutorial are you using to learn Java as surely it will describe these things for you. If not, I'm very surprised, but you could also look at the Oracle Java tutorials here: Methods, Constructors

[christopherx]

Sorry! Just dawned on me!! False alarm :)

[Fubarable]

Sorry! Just dawned on me!! False alarm :)

So you understand? If not:

public class Foo {
   // variables can be declared or declared and initialized here:
   int a; // declared
   int b = 3; // declared and initialized, 
   
   // but that's it. You can't do:
   b = b + 3;  // *** illegal ***
   
   // but must do it in a method or constructor:
   
   public void myMethod() {
      b = b + 3;  // this is OK
   }
}

[christopherx]

While we're here, I've just realised, obviously, that everything needs to be in a method. Completely rookie mistake on my part, sorry! One more thing though, and that's actually going about calling it.

public class GraphicsObj extends JPanel
{
public void paint(Graphics g)
{
// Set up Graphics object.
    super.paintComponent(g);
    this.setBackground(Color.WHITE);
    g.setColor(Color.blue);

    // Set Constants.
    final int XCOORD = 50;
    final int YCOORD = 50;
    final int RAD = 30;
    
    double xCurCoord = 0;
    double yCurCoord = 0;
    
    
    // Draw Circle using Circle Theorem.
for(int t=0;t<=360;t++)
{
    xCurCoord = XCOORD + (RAD * Math.cos(Math.toRadians(t)));
    yCurCoord = YCOORD + (RAD * Math.sin(Math.toRadians(t)));
    g.drawLine(XCOORD,YCOORD,(int)xCurCoord,(int)yCurCoord);
}
}
}

Basically, I dont know how to call this. It asks for a parameter of type Graphics, but whenever I try to pass it one when it's called it says that Graphics is an abstract and can not be instantiated. Any help?

[christopherx]

oh my lord im such an idiot..

Sorry, I just realised i don't need to treat it like that. Thankyou so much for your help, and I'm sorry i've asked two questions which i've answered myself.