Thread: ActionListener changing ImageIcons:

If you look at line 74 you will see my actionPerformed method where I want to switch the icon displayed on the JButton. I know I still have to add the images to the button however I am running into a few issues here.

Therefore my main question is, am I even approaching this problem correctly? In my next class it will be vital that I can decipher what each icon is display on the JButton. I am working on programing A* but I have to get everything talking first.

Please take a look at line 74, any advice would be greatly appreciated.

import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
 
import javax.swing.*;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
 
public class Screen implements ActionListener
{
	JButton start;
	JButton reset;
	JButton box[][] = new JButton[20][20];
	JLabel lbl;
	//Icons to be displayed in box[][]
	ImageIcon wall;
	ImageIcon begin;
	ImageIcon end;
 
	//counter how many time box[][] was pressed to enable
	//the Image Icons
	private int counter=0;
 
	Screen()
	{
		//main frame
		JFrame j = new JFrame("A* Algorithm");
 
		//setting main frame
		j.setSize(1200,500);
		j.setLayout(new BorderLayout());
		j.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 
		//create Panel for multi array buttons
		JPanel p = new JPanel();
		p.setLayout(new GridLayout(20,20));
 
		//create command buttons "start" and "restart"
		JPanel CmdBtns = new JPanel();
 
		//create buttons matrix of buttons
		for(int row=0;row<20;row++)
		{
			for(int col=0;col<20;col++)
			{   //create new matrix buttons
				box[row][col] = new JButton();
				//add buttons to panel
				p.add(box[row][col]);
			}
		}
 
		//create start button
		start = new JButton("Start");
		CmdBtns.add(start);
 
		//create reset button
		reset = new JButton("Reset");
		CmdBtns.add(reset);
 
		//Centering matrix buttons onto main JFrame
		j.add(p,BorderLayout.CENTER);
 
		//adding start and restart buttons
		j.add(CmdBtns,BorderLayout.SOUTH);
 
		j.setVisible(true);
	}
 
	//handling matrix buttons
	public void actionPerformed(ActionEvent ae)
	{
		//counting how many times button the the matrix was pressed
		counter++;
		//reseting counter to zero if the buttons was pressed three times
		counter%=3;
 
		if(ae.getActionCommand().equals(box))
		{
			switch(counter)
			{
			case 0:
				//display wall icon
				break;
			case 1:
				//display start icon
				break;
			case 2:
				//display end icon
				break;
 
				default:
					break;
 
			}
		}
	}
 
	public static void main(String[] args)
	{
		new Screen();
	}
 
}

am I even approaching this problem correctly?

Other than running the Swing app on the EDT, your approach seems okay, but it's not clear what the problem is, so a definite answer is not possible. What are the 400 buttons to do?

Some fine points at this "work in progress" stage:

1. The actionListener has not been added to any of the buttons.

2. The if statement condition:

(ae.getActionCommand().equals(box)

will not return true for individual button presses.

3. It's not clear if the counter is intended to count the number of presses on each button or on any button. Currently, it counts a press on any button, or, more accurately, on any entry into the actionPerformed() method.

Thanks for commenting your code.

The end statement of this program is to program A Star. When the buttons in the matrix is pressed different options will display to what it is . If it is pressed once the program will read it as a wall and know it cannot go this way. The other options will let the user pick the start and end points.

The counter is suppose to cycle through these options and if the button was not pressed it is a approved path to be checked on the open list.

I have also attached a new program. Which way to you think is better?

Class Screen

import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
 
import javax.swing.*;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
 
public class Screen
{
	JButton start;
	JButton reset;
	MatrixButtons[][] matrixButtons = new MatrixButtons[20][20];
 
	Screen()
	{
		//main frame
		JFrame j = new JFrame("A* Algorithm");
 
		//setting main frame
		j.setSize(1200,500);
		j.setLayout(new BorderLayout());
		j.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 
		//create Panel for multi array buttons
		JPanel p = new JPanel();
		p.setLayout(new GridLayout(20,20));
 
		//create command buttons "start" and "restart"
		JPanel CmdBtns = new JPanel();
 
		//create buttons matrix of buttons
		for(int row=0;row<20;row++)
		{
			for(int col=0;col<20;col++)
			{   //create new matrix buttons
				matrixButtons[row][col] = new MatrixButtons();
				//add buttons to panel
				p.add(matrixButtons[row][col]); //error on line
			}
		}
 
		//create start button
		start = new JButton("Start");
		CmdBtns.add(start);
 
		//create reset button
		reset = new JButton("Reset");
		CmdBtns.add(reset);
 
		//Centering matrix buttons onto main JFrame
		j.add(p,BorderLayout.CENTER);
 
		//adding start and restart buttons
		j.add(CmdBtns,BorderLayout.SOUTH);
 
		j.setVisible(true);
	}
 
	public static void main(String[] args)
	{
		new Screen();
	}
 
}

Class MatrixButtons

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
 
import javax.swing.ImageIcon;
 
public class MatrixButtons extends Screen implements ActionListener 
{
	//Icons to be displayed in box[][]
		ImageIcon wall;
		ImageIcon begin;
		ImageIcon end;
 
		byte value =0;
		/*
		 0:nothing
		 1:wall
		 2:begin
		 3:end
		 */
 
		MatrixButtons()
		{
			wall = new ImageIcon(this.getClass().getResource("wall.png"));
			begin = new ImageIcon(this.getClass().getResource("begin.png"));
			end = new ImageIcon(this.getClass().getResource("end.png"));
			matrixButtons.addActionListener(new ActionListener());  //error on line
		}
 
		public void actionPerformed(ActionEvent ae) 
		{
			value++;
			value%=3;
 
			switch(value)
			{
			case 0:
				setIcon(wall);   //error on line
				break;
			case 1:
				setIcon(begin); //error on line
				break;
			case 2:
				setIcon(end);   //error on line
				break;
 
				default:
					break;
			}
 
		}
 
}

I'm not quite getting it, but I think what you've described will require keeping track of how many times each button is pressed. If that's the case, you may want each matrix button to extend JButton so that you can add the press counter to the matrix button class.

I have also attached a new program. Which way to you think is better?

I won't compare each line of 2 different posts to determine the differences and then give an opinion as to which is better. The real test for which is better is to determine which one most accurately accomplishes what you're trying to do while providing the ability to grow easily into what you need it to do next.

Since this is a work in progress with unclear requirements, I can't make those judgments.

Yes I want to keep track of how many times each button is pressed and reset each button every third time it is pressed.

To start off it is set to null
press once it is set to wall
pressed twice set to begin
pressed three times, set to end
pressed fourth time it is back to null and the process repeats for each button.

The above buttons will be used to find a path, if it is null it will be check to see if it is one of the nodes on the shortest path, walls will not be checked and the program will start from the “start” icon and end when it find the “end” icon.

I posted this question in another forum and seen someone mentioned something about map<JButton,Integer>. However I was thinking this might be a little over kill, opinion? I am more familiar with C++ and trying to learn swing and get better at java. Thought this would be a fun challenging project and I appreciate the advice.

A* Algorithm with Python-Pygame - YouTube
This above link is something like what I am trying to do. I will eventually add a few more path find algorithms to the options but one step at a time.

Yes norm I posted at a different forum too. I do not understand? Do you think I am trying to play or mislead posters on here? Is there some ethic I am unaware of against asking the question in two different places? I even posted on that forum that I posted on here? I really appreciate the advice, didn't mean to rub you the wrong way.