如何声明JComboBox？

Question

I was creating a program to work with a drop-down list, but I got stuck at the line of declaration of JComboBox box, I get these error messages: Multiple markers at this line - The constructor JComboBox(String[]) is undefined - Line breakpoint:JComboBox [line: 25] - JComboBox() No matter how I try to define JComboBox, I get some sort of error. Please help me with it.

Here's the code of the public class:

    import javax.swing.*;
    import java.awt.FlowLayout;
    import java.awt.Font;
    import javax.swing.JFrame;
    import javax.swing.JTextField;
    import javax.swing.JRadioButton;
    import javax.swing.ButtonGroup;
    import java.awt.event.ItemListener;
    import java.awt.event.ItemEvent;

    public class JComboBox extends JFrame {

        private JComboBox box;
        private JLabel picture;

        private static String[] filename = { "p.png", "i.png" };
        private Icon pics[] = { new ImageIcon(getClass().getResource(filename[0])),
                new ImageIcon(getClass().getResource(filename[1])) };

        public JComboBox() {

            super("This is the title");
            setLayout(new FlowLayout());

            JComboBox box = new JComboBox(filename);

            box.addItemListener(new ItemListener() {
                public void itemStateChanged(ItemEvent event) {
                    if (event.getStateChange() == ItemEvent.SELECTED) {
                        picture.setIcon(pics[box.getSelectedIndex()]);
                    }
                }
            });

            add(box);
            picture = new JLabel(pics[0]);
            add(picture);

        }

    }

And here's the code of the main class:

    import javax.swing.*;

    public class JComboBox1 extends JFrame {

        public static void main(String[] args) {


            JComboBox Box = new JComboBox();
            Box.setVisible(true);
            Box.setSize(400,400);
            Box.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        }

    }

Thank you.

Answer 1

Your problem, as @Andy mentioned is that you have a collision in the name of your class and the swing component. If you absolutely must name your class JComboBox you'll have to reference the swing component by the fully-qualified name, as such

public class JComboBox extends JFrame {

    private javax.swing.JComboBox box;

If you hover over your private instance with an IDE you should see the fully-qualified name matching the package in which you've created your JComboBox class. Save yourself some pain and rename your class.