Adding a MouseListener to a panel

Question

I am trying to add the mouse actions to my panel. This is what the program is supposed to do:

Write a program that allows the user to specify a triangle

Answer 1

I don't see anywhere you instantiate class MouseListen. Also you need to call addMouseListener().

Here are lines from something I wrote a while back that worked:

public class ColorPanel extends JPanel implements MouseListener {

   . . .

ColorPanel(JTextField jTextFieldColor) {
    super();
    this.jTextField = jTextFieldColor;
    addMouseListener(this);
}

@Override
public void mouseClicked(MouseEvent evt) {
    System.out.println("Instance of ColorPanel clicked.");
    jColorChooser = new JColorChooser(this.getBackground());
    this.add(jColorChooser);
    int retval = JOptionPane.showConfirmDialog(null,
            jColorChooser,
            "JOptionPane Example : ",
            JOptionPane.OK_CANCEL_OPTION,
            JOptionPane.PLAIN_MESSAGE);
    if (retval == JOptionPane.OK_OPTION) {
        jTextField.setText(Utils.hexStringFromColor(jColorChooser.getColor()));
    }
}

See the tutorial at https://docs.oracle.com/javase/tutorial/uiswing/events/mouselistener.html.

Also, based on https://docs.oracle.com/javase/tutorial/uiswing/events/eventsandcomponents.html, you might be able to have your JFrame implement the MouseListener, which would make your code even simpler. (You wouldn't need class MouseListen at all.)

A quick grep though past Java code I've written confirms you could

public class MyFrame extends JFrame implements MouseListener

so you might want to look into this.