How to add a MouseListener to a frame

Question

I want to add a mouselistener to the mt JFrame frame, but when I do frame.addMouseListener (this), I get an error message that I cannot use in the static method

I am making an application that detects a mouse click and then displays it in int clicks

code

import java.awt.BorderLayout; import java.awt.Color; import java.awt.FlowLayout; import java.awt.Font; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import javax.swing.BorderFactory; import javax.swing.JFrame; import javax.swing.JTextField; public class numberOfClicks implements MouseListener{ static int clicks = 0; @Override public void mouseClicked(MouseEvent e) { clicks++; } static JTextField text = new JTextField(); static String string = clicks+" Clicks"; static JFrame frame = new JFrame("Click Counter"); public static void frame(){ Font f = new Font("Engravers MT", Font.BOLD, 23); text.setEditable(false); text.setBackground(Color.BLUE); text.setFont(f); text.setForeground(Color.GREEN); text.setBorder(BorderFactory.createLineBorder(Color.BLUE)); text.setText(string); frame.add(text, BorderLayout.SOUTH); frame.setResizable(false); frame.setSize(300, 300); frame.getContentPane().setBackground(Color.BLUE); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setVisible(true); frame.addMouseListener(this); } public static void main(String[] args){ frame(); } @Override public void mousePressed(MouseEvent e) {} @Override public void mouseEntered(MouseEvent e) {} @Override public void mouseExited(MouseEvent e) {} @Override public void mouseReleased(MouseEvent e) {} } 

Answer 1

this does not exist in a static method, since a static method is a method of a class, not an object (owner of this ). Solution: get rid of all the statics from your code above. None of your fields or methods above should be static except the main method.

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Edit
And as Andrew Thompson correctly says, add a MouseListener to the JPanel, which is added to the JPrame contentPane.

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Edit 2

• You will want to learn and use the Java naming conventions. Class names (i.e. N umberOfClicks) must begin with an uppercase letter. The names of methods and variables with a lowercase letter.
• You better use the mousePressed(...) method rather than mouseClicked(...) , as the former is less important for accepting presses.
• You will also want to set the JTextField text in your mousePressed(...) method, since changing the value of the clicks is not enough to change the display.
• I try to prevent my listeners from implementing my GUI classes (or "view"). I prefer to use anonymous inner classes or autonomous classes where possible.

eg,

  JPanel mainPanel = new JPanel(); mainPanel.addMouseListener(new MouseAdapter() { @Override public void mousePressed(MouseEvent e) { clicks++; text.setText(clicks + " Clicks"); } }); // add mainPanel to the JFrame...