Simple JPanel question

[Rebecca Weber]

Hey guys,
I am taking a beginning course in Java. I am working on a simple program to draw circles. I have to create a JFrame and embed a JPanel into the JFrame. I am not sure if I have this set up properly, but when I run the program nothing appears in the JPanel. I just need some help getting the circle to appear in the JPanel. Here is my code:

//create a circle on the JPanel that's embedded in the JFrame
import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JPanel;
import javax.swing.JFrame;

public class Circles
{
	public static void main (String[] args)
	{
		//create frame for myPanel
		JFrame frame = new JFrame("Circles");
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		
		JPanel myPanel = new JPanel(); // create myPanel
		myPanel.setBackground(Color.WHITE);
		frame.add( myPanel ); // add myPanel to frame
		frame.setSize( 400, 400 ); // set frame size
		frame.setVisible( true ); // display frame
	}//end main
}
class CirclesPanel extends JPanel
{
	public void paintComponent(Graphics g)
	{
		//call superclass's paint method
		super.paintComponent(g);
		
		//make color of circles black
		g.setColor(Color.BLACK);
		g.drawArc(25, 50, 50, 50, 0, 360);
	}
}

Any help is appreciated. Thanks.

[Darryl Burke]

Hi Rebecca, and welcome to the Ranch! Whenever you post here, please use the code tags -- highlight your code and click the Code button above the editing area. Since you're new here, I've added the tags for you and you can see how much more readable the code is now.

You have a CirclesPanel class that isn't used in the GUI, where you add a simple JPanel with its background set to WHITE. That isn't going to automagically run the painting code in your custom class -- to use that, you have to actually construct an instance of the class and display it in the GUI.

[Rebecca Weber]

Darryl Burke wrote:Hi Rebecca, and welcome to the Ranch! Whenever you post here, please use the code tags -- highlight your code and click the Code button above the editing area. Since you're new here, I've added the tags for you and you can see how much more readable the code is now.

You have a CirclesPanel class that isn't used in the GUI, where you add a simple JPanel with its background set to WHITE. That isn't going to automagically run the painting code in your custom class -- to use that, you have to actually construct an instance of the class and display it in the GUI.

Darryl,

Thank you for the advice. I apologize about the code tags, I will remember for next time.
Rebecca