Question

In Java Swing, in my ButtonHandler class, I need to have 2 different showDialog messages show when my acceptbutton1 is pressed. One message is if the mouse HAS been dragged. One is if the mouse HAS NOT been dragged.

/// I tried to make the Points class or the Mouse Dragged function return a boolean of true, so that I could construct an IF/THEN statement for the showDialog messages, but my boolean value was never accepted by ButtonHandler.

*************************ButtonHandler class************************************

import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;

public class ButtonHandler extends JFrame implements ActionListener {
  
private final JButton acceptbutton1;
private final JButton cancelbutton1;
private final JPanel buttonPanel;
private final JPanel mainPanel;
  
public ButtonHandler() {
  
super();
  
mainPanel = new JPanel();
buttonPanel = new JPanel(new FlowLayout());
  
cancelbutton1 = new JButton("Cancel");
acceptbutton1 = new JButton("Accept");
  
mainPanel.add(buttonPanel);
  
add(mainPanel);
  
cancelbutton1.addActionListener(this);
acceptbutton1.addActionListener(this);
  
  
}
  
public JButton getAcceptbutton1() {
return acceptbutton1;
}
  
public JButton getCancelbutton1() {
return cancelbutton1;
}

  
@Override
public void actionPerformed(ActionEvent e) {
if(e.getSource() == acceptbutton1)
////// AND && dragged the mouse
/////THEN
JOptionPane.showMessageDialog(this,"Nice drawing");
////ELSE
JOPtionPane.showMessageDialog(this,"Please try again");
  
if(e.getSource() == cancelbutton1)
JOptionPane.showConfirmDialog(this, "You pressed Cancel button");
}
}
***********************Painter main class************************************

import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.*;

public class Painter {

public static void main(String[] args) {

  
JFrame application = new JFrame();

PaintPanel paintPanel = new PaintPanel();
application.add(paintPanel, BorderLayout.CENTER);
  

application.add(new JLabel("Draw"),
BorderLayout.NORTH);
  
  
ButtonHandler buttonHandler = new ButtonHandler();
  
JPanel panel = new JPanel();
panel.setLayout(new FlowLayout());
panel.add(buttonHandler.getAcceptbutton1());
panel.add(buttonHandler.getCancelbutton1());
application.add(panel,BorderLayout.SOUTH);

application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
application.setLocationRelativeTo(null);
application.setSize(600, 400);
application.setVisible(true);
}
}
**********************Point class, for the graphics in PaintPanel************************

public class Point {
  
public int x;
public int y;
  
public Point() {
this.x = 0;
this.y = 0;
  
}
public Point (int x, int y) {
this.x = x;
this.y = y;
  
}
public int getX() {
return x;
}
public int getY() {
return y;
}
  
}
******************PaintPanel*******************************************************

import java.awt.Graphics;
import java.awt.Point;
import java.awt.event.MouseMotionAdapter;
import java.awt.event.MouseEvent;
import java.util.ArrayList;
import javax.swing.JPanel;

public class PaintPanel extends JPanel {
  
private final ArrayList<Point> points = new ArrayList<>();
  

  
public PaintPanel() {
  
addMouseMotionListener(
new MouseMotionAdapter() {
@Override
public void mouseDragged(MouseEvent event) {

points.add(event.getPoint());
repaint();
}
});
  
}
@Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
for (Point point : points ) {
g.fillRect(point.x, point.y, 4,6);
  

}
}
}

Answer 1

Below is the solution:

changed the code of ButtonHandler.java and the PaintPanel.java some of the code to checked the mouse is dragged or not.

import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;

public class ButtonHandler extends JFrame implements ActionListener {

   private final JButton acceptbutton1;
   private final JButton cancelbutton1;
   private final JPanel buttonPanel;
   private final JPanel mainPanel;

   public ButtonHandler() {

       super();

       mainPanel = new JPanel();
       buttonPanel = new JPanel(new FlowLayout());

       cancelbutton1 = new JButton("Cancel");
       acceptbutton1 = new JButton("Accept");

       mainPanel.add(buttonPanel);

       add(mainPanel);

       cancelbutton1.addActionListener(this);
       acceptbutton1.addActionListener(this);

   }

   public JButton getAcceptbutton1() {
       return acceptbutton1;
   }

   public JButton getCancelbutton1() {
       return cancelbutton1;
   }

   @Override
   public void actionPerformed(ActionEvent e) {
       if (e.getSource() == acceptbutton1) {
           if (PaintPanel.p == true) //check for the PaintPanel is draw a paint on the panel or not and display a message
               JOptionPane.showMessageDialog(this, "Nice drawing");
           else
               JOptionPane.showMessageDialog(this, "Please try again...");
       }

       if (e.getSource() == cancelbutton1)
           JOptionPane.showConfirmDialog(this, "You pressed Cancel button");
   }
}

import java.awt.Graphics;
import java.awt.Point;
import java.awt.event.MouseMotionAdapter;
import java.awt.event.MouseEvent;
import java.util.ArrayList;
import javax.swing.JPanel;

public class PaintPanel extends JPanel {
   static boolean p=true; //declare static variable to check the paintComponent ork changed the value to true
   private final ArrayList<Point> points = new ArrayList<>();

   public PaintPanel() {

       addMouseMotionListener(new MouseMotionAdapter() {
           @Override
           public void mouseDragged(MouseEvent event) {
               points.add(event.getPoint());
               repaint();
           }
       });

   }

   @Override
   public void paintComponent(Graphics g) {
       super.paintComponent(g);
       for (Point point : points) {
           g.fillRect(point.x, point.y, 4, 6);
           p=false; //changed the value to true
       }
   }
}

sample output:

Answer 2

To implement different

To implement different showDialog messages in your ButtonHandler class based on whether the mouse has been dragged or not, you can make use of a boolean variable to track the dragging state. Here's an updated version of your code with the necessary modifications:

javaCopy codeimport java.awt.FlowLayout;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JOptionPane;import javax.swing.JPanel;public class ButtonHandler extends JFrame implements ActionListener {  
  private final JButton acceptbutton1;  private final JButton cancelbutton1;  private final JPanel buttonPanel;  private final JPanel mainPanel;  private boolean mouseDragged; // Track dragging state

  public ButtonHandler() {    super();
    mainPanel = new JPanel();
    buttonPanel = new JPanel(new FlowLayout());
    cancelbutton1 = new JButton("Cancel");
    acceptbutton1 = new JButton("Accept");
    mainPanel.add(buttonPanel);
    add(mainPanel);

    cancelbutton1.addActionListener(this);
    acceptbutton1.addActionListener(this);    // Initialize dragging state to false
    mouseDragged = false;
  }  public JButton getAcceptbutton1() {    return acceptbutton1;
  }  public JButton getCancelbutton1() {    return cancelbutton1;
  }  @Override
  public void actionPerformed(ActionEvent e) {    if (e.getSource() == acceptbutton1) {      if (mouseDragged) { // Check dragging state
        JOptionPane.showMessageDialog(this, "Nice drawing");
      } else {
        JOptionPane.showMessageDialog(this, "Please try again");
      }
    }    if (e.getSource() == cancelbutton1) {
      JOptionPane.showConfirmDialog(this, "You pressed Cancel button");
    }
  }  // Setter method to update dragging state
  public void setMouseDragged(boolean mouseDragged) {    this.mouseDragged = mouseDragged;
  }
}

In the PaintPanel class, you need to add a method to update the dragging state in the ButtonHandler class. Here's the modified PaintPanel class:

javaCopy codeimport java.awt.Graphics;import java.awt.Point;import java.awt.event.MouseMotionAdapter;import java.awt.event.MouseEvent;import java.util.ArrayList;import javax.swing.JPanel;public class PaintPanel extends JPanel {  private final ArrayList<Point> points = new ArrayList<>();  private final ButtonHandler buttonHandler; // Reference to ButtonHandler

  public PaintPanel(ButtonHandler buttonHandler) {    this.buttonHandler = buttonHandler;
    addMouseMotionListener(new MouseMotionAdapter() {      @Override
      public void mouseDragged(MouseEvent event) {
        points.add(event.getPoint());
        buttonHandler.setMouseDragged(true); // Update dragging state
        repaint();
      }
    });
  }  @Override
  public void paintComponent(Graphics g) {    super.paintComponent(g);    for (Point point : points) {
      g.fillRect(point.x, point.y, 4, 6);
    }
  }
}

And finally, in your Painter class, you need to pass the ButtonHandler instance to the PaintPanel constructor. Here's the updated Painter class:

javaCopy codeimport java.awt.BorderLayout;import java.awt.FlowLayout;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JPanel;public class Painter {  public static void main(String[] args) {    JFrame application = new JFrame();    PaintPanel paintPanel = new PaintPanel(new ButtonHandler());
    application.add(paintPanel, BorderLayout.CENTER);
    application.add(new JLabel("Draw"), BorderLayout.NORTH);    ButtonHandler buttonHandler = (ButtonHandler) paintPanel.buttonHandler;
    JPanel