Need help understanding how a specific getter affects my program - java

I'm very new to coding(2 months) and i attempted to make Tic-Tac-Toe in java. I'm in a little over my head but i managed to create it using swing. My main problem is in the button1 class. I was going to use the getText() method but ended up not needing it or so i thought. I tried deleting it but as it turns out my tictactoe buttons don't switch letters without it. The compiler told me it overrides AbstractButton's getText() method but i don't see why that should matter since i never actually used it i thought. I'm thinking it's maybe a scope issue handled by it being overwritten somehow but i'm not sure. I was trying to use the text variable to update the button with setText() and that doesn't seem to work like i thought it should. I also don't understand why the 3 by 3 gridlayout seems to work properly most of the time but sometimes the number of buttons added is wrong.
So in summation the program works(mostly) but i'm not fully understanding how the button1 class is working.
TicTacToe.java
import java.awt.*;
import java.util.*;
import javax.swing.*;
public class TicTacToe extends JFrame {
public static void main(String[] args) {
JFrame window = new JFrame("Tic-Tac-Toe");
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.setVisible(true);
window.setSize(600, 600);
window.setLayout(new GridLayout(3, 3));
ArrayList<button1> buttonArrayList = new ArrayList<>(9);
for (int i = 0; i < 9; i++) {
button1 newbutton = new button1();
buttonArrayList.add(newbutton);
window.add(buttonArrayList.get(i));
}
}
}
button1.java
import java.awt.*;
import java.awt.event.ActionEvent;
import javax.swing.AbstractAction;
import javax.swing.JButton;
public class button1 extends JButton {
int value = 0;
String text = "";
public button1() {
class ButtonAction extends AbstractAction {
public ButtonAction() {}
#Override
public void actionPerformed(ActionEvent Switcher) {
System.out.println(text + " " + value);
value++;//value is a relic from earlier attempts that i just felt like keeping.
if (text.equals("O")) {
text = "X";
} else if (text.equals("X")) {
text = "";
} else if (text.equals("")) {
text = "O";
}
}
}
this.setAction(new ButtonAction());
this.setText(text);
this.setFont(new Font("Arial",Font.PLAIN,120));
}
public String getText()// <----culprit
{
return text;
}
}

A JButton class has a methods defined for it, including setText() (which will set the displayed text on the button) and getText() (which will return the current text that is displayed on the button).
You created a class button1 (note: classes should start with Capital Letters).
You added an Action to the button1 class, which means that when the action is activated, something happens. Note that in that actionPerformed method, you should call setText(text) to update the displayed value.
You have also defined a getText() method that overrides the getText() method defined in JButton. This approach is fine if it is a conscious design decision. As it is, I think you should remove the getText() method from the button1 class, and allow the standard JButton class to handle the update. Right now, you are attempting to keep an instance variable text with the value, but it is possible for that instance variable to not be in alignment with the actual displayed value of the button (consider another class calling .setText() on the button).
EDIT: It is true that this referring to the JButton in the ButtonAction is not available. However, the Action itself contains the button that was pressed.
#Override
public void actionPerformed(ActionEvent e)
{
JButton btn = (JButton)e.getSource();
// if desired, String cur = btn.getText() may be called to find the
// current setting; get and process if needed
btn.setText(WHAT_EVER_TEXT);
}
Unless it is a specific requirement to process the current text, however (allowing selecting an O to an X to a blank), I would implement something to keep track of the current turn. This code is something I was experimenting with, and has good and bad points to it (as it is illustrative):
static class TurnController
{
// whose turn it is; start with X
private Player whoseTurn = Player.X;
// the instance variable
private static final TurnController instance = new TurnController();
private TurnController()
{
}
public static Player currentTurn()
{
return instance.whoseTurn;
}
public static Player nextTurn()
{
switch (instance.whoseTurn) {
case X:
instance.whoseTurn = Player.O;
break;
case O:
instance.whoseTurn = Player.X;
break;
}
return instance.whoseTurn;
}
public static String getMarkerAndAdvance()
{
String marker = currentTurn().toString();
nextTurn();
return marker;
}
enum Player
{
X,
O,
;
}
}
Using this TurnController, the actionPerformed becomes:
#Override
public void actionPerformed(ActionEvent e)
{
JButton btn = (JButton)e.getSource();
btn.setText(TurnController.getMarkerAndAdvance());
}
and the Button1 class may have the String text instance variable removed.

What you have tried is Try to make a Custom Button Class and its EventHandler just by extending AbstractAction namee button1 as we See in Your Question.
You have Override the method actionPerformed(ActionEvent Switcher) which actually belongs to Class AbstractAction by your own definition (What should Performed on Action Event of Every Button).
class ButtonAction extends AbstractAction {
public ButtonAction() {}
#Override
public void actionPerformed(ActionEvent Switcher) { // Your Definition For actionPerformed..
System.out.println(text + " " + value);
value++;//value is a relic from earlier attempts that i just felt like keeping.
if (text.equals("O")) {
text = "X";
} else if (text.equals("X")) {
text = "";
} else if (text.equals("")) {
text = "O";
}
}
}
this.setAction(new ButtonAction()); // add ActionListener to each Button.
this.setText(text); // Setting Text to each Button
this.setFont(new Font("Arial",Font.PLAIN,120)); //add Font to each Button.
}
Now In this Code.
ArrayList buttonArrayList = new ArrayList<>();
for (int i = 0; i < 9; i++) {
button1 newbutton = new button1(); // Creating 9 new buttons.
buttonArrayList.add(newbutton); // add each button into the ArrayList.
window.add(buttonArrayList.get(i)); // each Button to the the AWT Window.
}
Above Code will generate 9 Button and add it to Your AWT Window. each button have actionPerformed() method which contains the overrided Definition.
Now Each button will performed action as per the definition you give to actionPerformed() Method.
Thank You.

Related

Two different buttons in one Panel in my own Component

I'm trying to create JPanel with two different buttons which one of them increasing and second decreasing size of text or window. I have class with button declaration. Everything is working when I put these buttons on JFrame separately.
I don't know how to get Action Listener in JPanel of each buttons. All I possibly do is listener of mouse click on JPanel...
Could you help me? I'm really begginer with coding so be polite please :]
public class ButtonMy extends Component {
private ButtonIncrease increase;
private PropertyChangeSupport propertyChangeSupport;
public ButtonMy() {
setPreferredSize(new Dimension(30,30));
kolor = Color.blue;
setForeground(kolor);
propertyChangeSupport = new PropertyChangeSupport(this);
increase = ButtonIncrease.Powieksz;
}
public ButtonIncrease getIncrease() {
return increase;
}
public void setIncrease(ButtonIncrease increase) {
ButtonIncrease oldIncrease = this.increase;
this.increase = increase;
propertyChangeSupport.firePropertyChange("increase", oldIncrease, increase);
}
public void addPropertyChangeListener(PropertyChangeListener l) {
propertyChangeSupport.addPropertyChangeListener(l);
}
public void removePropertyChangeListener(PropertyChangeListener l) {
propertyChangeSupport.removePropertyChangeListener(l);
}
}
There is JPanel for bind 2 buttons. Here is the biggest problem :/ I'm lack of ideas.
public class ButtonB extends JPanel implements ActionListener{
public ButtonMy b1 = new ButtonMy();
public ButtonMy b2 = new ButtonMy();
public ButtonB (){
init();
}
public final void init(){
setLayout(new GridLayout(1,2));
this.przycisk1.setIncrease(ButtonIncrease.Powieksz);
this.przycisk2.setIncrease(ButtonIncrease.Zmniejsz);
add(b1);
add(b2);
}
}
JFrame where I test this component is very common. Code below shows only function for inc and dec size when separate button is clicked (not in JPanel).
private void buttonMy3MouseClicked(java.awt.event.MouseEvent evt) {
switch(buttonMy3.getIncrease()) {
case Powieksz: setSize(1);
break;
case Zmniejsz: setSize(0);
break;
}
}
I didn't paste full of my code. There some of math functions left which I think they are not needed here (setSize for example).
I'm not sure if i understand the problem correctly but I think under the actionListener class you should have a method called actionPerformed& it will say that if button1 is clicked increase the number, if button2 is clicked decrease the number:
public void actionPerformed( ActionEvent event ) {
if (event.getSource()== b1) // your "increase size" code
if(event.getSource()== b2)// your "decrease size" code
}
button listeners are actually different from mouse listeners; buttons implements ActionListeners and have the actionPerformed method with event variable. you could handle the event by:
getSource() -this method is inherited from java.util.EventObject and returns the OBJECT on which the event initially occurred (the button itself)
or by getActionCommand() -this method is available to action events, or any event that inherits from ActionEvent and returns the command STRING associated with this action.
however mouse listeners implements MouseListener and has a lot of methods depending on what the mouse does (pressed, clicked, released, etc.).

JTextArea.append not displaying

I'm trying to write the contents of an array to a JTextArea. I've tried everything I can think of, and I can't understand what isn't working here. I've stripped the unnecessary stuff out of my code, here's the two relevant classfiles:
Main class:
package irclogtest;
public class BriBotMain {
public static void main(String args[]) throws Exception {
boolean startup = true;
//frame test launch
BriDisplayGUI data = new BriDisplayGUI(startup);
data.irclog.append("BriBot Startup Successful!" + "\n");
//example access through function when startup is false (only in main class for sample code to demonstrate issue)
try {
BriDisplayGUI data2 = new BriDisplayGUI(false); //tells us which class we're accessing
String[] textForGUI = new String[2]; //tells us the array has 2 lines
textForGUI[0] = "this is the first line"; //set the first line of the array to this text
textForGUI[1] = "this is the second";
data2.arrayToDisplay(textForGUI); //appends contents of array to text window
}
catch(Exception e) {
System.out.println(e);
}
}
}
GUI display class:
package irclogtest;
import java.awt.event.*;
import java.io.IOException;
import javax.swing.*;
public class BriDisplayGUI extends JFrame implements ActionListener {
private static final long serialVersionUID = -7811223081379421773L;
String file_name = "C:/Bribot/logfile.txt";
//these lines create the objects we use
JFrame frame = new JFrame();
JPanel pane = new JPanel();
JButton pressme = new JButton("Click here");
JButton pressme2 = new JButton("Also here");
JTextArea irclog = new JTextArea( 20, 70);
JScrollPane scrollirc = new JScrollPane(irclog);
public BriDisplayGUI(boolean startup) { //startup function, opens and sets up the window
if(startup == true){
frame.setTitle("Bribot Test Frame"); frame.setBounds(100,100,840,420); //sets title of window, sets position and size of window
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //tells program to end on window close
frame.add(pane); //adds the main display pane to the window
//panel customization goes here
pressme.addActionListener(this);
pane.add(pressme);
pressme2.addActionListener(this);
pane.add(pressme2);
pressme.requestFocusInWindow();
irclog.setEditable(false);
scrollirc.setVerticalScrollBarPolicy( JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
pane.add(scrollirc);
irclog.setLineWrap(true);
irclog.setWrapStyleWord(true);
//pane.add(inputthing);
frame.setVisible(true);
} else {
System.out.println("Display Class Called");
}
}
public void arrayToDisplay(String[] text) throws IOException {
int i;
for ( i=0; i < text.length; i++) {
irclog.append( text[i] + "\n");
System.out.println( i + ": " + text[i]);
}
}
public void singleToDisplay(String text) throws IOException {
irclog.append(text + "\n");
System.out.println(text);
}
//basic event handler
public void actionPerformed(ActionEvent event) {
Object source = event.getSource();
if (source == pressme) {
} else if(source == pressme2) {
}
}
}
The first append works fine, but the second doesn't, and I can't figure out why (although the for loop does, as the contents of the array get written to console). I've searched quite a bit and nothing I've tried works. Can anyone point out the inevitable obvious oversight here? I'm the definition of a novice, so any advice is appreciated.
Thanks!
The default constructor doesn't do anything, meaning it doesn't construct any kind of UI or display, what would be, an empty frame.
You seem to be thinking the text will appear in data when you are appending it to data1
Try calling this(false) within the default constructor
A better solution would be to construct the core UI from the default constructor and from the "startup" constructor call this() and then modify the UI in what ever way this constructor needs
It seems like you write a new program. Why do you use Swing? Did you take a look at JavaFX?
I am not sure if that is going to fix your problem but you could try a foreach
for(String s : text){
irclog.append(s+"\n");
}

Combination Lock (Java)

I have a school assignment that i need to create. Below is the info:
Create a frame with ten buttons, labeled 0 through 9. To exit the program, the user must click on the correct three buttons in order, something like 7-3-5. If the wrong combination is used, the frame turns red.
I already finish the frame and the buttons with online research helps, but i just cant make the functionality to work. Please take a look at my codes and thanks in advance.
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class ComboNumber extends JFrame implements ActionListener{
//variable declaration
int ans1 = 3;
int ans2 = 7;
int ans3 = 1;
int one, two, three;
String inData1, inData2, inData3;
JButton[] button;
//constructs the combolock object
public ComboNumber()
{
//sets flowlayout
getContentPane().setLayout(new FlowLayout());
Container c = getContentPane();
//creates buttons
button = new JButton[10];
for(int i = 0; i < button.length; ++i) {
button[i] = new JButton("" + i);
//adds buttons to the frame
c.add(button[i]);
//registers listeners with buttons
button[i].addActionListener(this);
}
//sets commands for the buttons (useless)
//sets title for frame
setTitle("ComboLock");
}
//end combolock object
//listener object
public void actionPerformed(ActionEvent evt)
{
Object o = evt.getSource();
for(int i = 0; i < button.length; ++i) {
if(button[i] == o) {
// it is button[i] that was cliked
// act accordingly
return;
}
}
}
//end listener object
//main method
public static void main (String[] args)
{
//calls object to format window
ComboNumber frm = new ComboNumber();
//WindowQuitter class to listen for window closing
WindowQuitter wQuit = new WindowQuitter();
frm.addWindowListener(wQuit);
//sets window size and visibility
frm.setSize(500, 500);
frm.setVisible(true);
}
//end main method
}
//end main class
//window quitter class
class WindowQuitter extends WindowAdapter
{
//method to close the window
public void windowClosing(WindowEvent e)
{
//exits the program when the window is closed
System.exit(0);
}
//end method
}
//end class
The basic idea is simple.
You need two things.
What the combination actually is
What the user has guessed
So. You need to add two variables. One contains the combination/secret, the other contains the guesses.
private String secret = "123";
private String guess = "";
This allows you to make the combination as long as you like ;)
Then in your actionPerformed method, you need to add the most recent button click to the guess, check it against the secret and see if they've made a good guess. If the length of the guess passes the number of characters in the secret, you need to reset the guess.
public void actionPerformed(ActionEvent evt) {
Object o = evt.getSource();
if (o instanceof JButton) {
JButton btn = (JButton) o;
guess += btn.getText();
if (guess.equals(secret)) {
JOptionPane.showMessageDialog(this, "Welcome Overloard Master");
dispose();
} else if (guess.length() >= 3) {
JOptionPane.showMessageDialog(this, "WRONG", "Wrong", JOptionPane.ERROR_MESSAGE);
guess = "";
}
}
}

Make text in JButton not visible

I made a button and did a .setText() on it because I have to compare the value of the .setText() with something else.
I applied the .setText() to a JButton, but I don't want the text to be visible in my button.
If I do setVisible(false) then it hides the whole button, but I only want it to hide the text.
Is there an option for this? I've considered making a custom font and apply it on the text in the .setText() but I'm wondering if there's a more efficient option to my problem.
Thanks in advance guys.
EDIT: I can't use .setText(" ") because I have to compare the value within it.
You state:
EDIT: I can't use .setText(" ") because I have to compare the value within it.
Nonsense. As I've mentioned in a comment, set the JButton's text to " ", and don't use the JButton's text for comparison. Instead use its actionCommand easily obtained via getActionCommand(). Or use a HashMap<JButton, SomethingElse>.
You may consider changing the JButton's Action when you need to change its behavior and state which is easily done by calling setAction(...)
For example,
import java.awt.event.ActionEvent;
import javax.swing.*;
public class ButtonActions {
private static void createAndShowGui() {
JPanel mainPanel = new JPanel();
JButton myButton = new JButton();
StartAction startAction = new StartAction();
PauseAction pauseAction = new PauseAction();
BlankAction blankAction = new BlankAction();
startAction.setNextAction(pauseAction);
pauseAction.setNextAction(blankAction);
blankAction.setNextAction(startAction);
myButton.setAction(startAction);
mainPanel.add(myButton);
JFrame frame = new JFrame("ButtonActions");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
class SwappingAction extends AbstractAction {
private Action nextAction;
public SwappingAction(String text) {
super(text);
}
public void setNextAction(Action nextAction) {
this.nextAction = nextAction;
}
public Action getNextAction() {
return nextAction;
}
#Override
/**
* super method needs to be called in child for swap to work
*/
public void actionPerformed(ActionEvent e) {
System.out.println("ActionCommand: " + e.getActionCommand());
((AbstractButton)e.getSource()).setAction(nextAction);
}
}
class StartAction extends SwappingAction {
public static final String START = "Start";
public StartAction() {
super(START);
}
#Override
public void actionPerformed(ActionEvent e) {
super.actionPerformed(e);
// start-specific code goes here
}
}
class PauseAction extends SwappingAction {
public static final String PAUSE = "Pause";
public PauseAction() {
super(PAUSE);
}
#Override
public void actionPerformed(ActionEvent e) {
super.actionPerformed(e);
// pause-specific code goes here
}
}
class BlankAction extends SwappingAction {
public static final String BLANK = " ";
public BlankAction() {
super(BLANK);
}
#Override
public void actionPerformed(ActionEvent e) {
super.actionPerformed(e);
}
}
Write buttonName.setText(" ") this will not display any name to the button. And whenever you feel like displaying the name (on any event) then set it again buttonName.setText("some text")
If you insist not to use setText(""), try setting same colour as a background colour and text colour. Check the below links
setBackground(java.awt.Color)
setForeground(java.awt.Color)
Why don't you name the first button " " (1 space).
the second: " " (2 spaces)
the third: " "(3 spaces) and so on ..
Now, compare:
if((event.getActionCommand()).equals(" "))
{ //1st button }
if((event.getActionCommand()).equals(" "))
{ //2nd button }
..and so on
where event is an object of ActionEvent
This way the buttons will have a unique names and be invisible.
Horrible coding, I know. But it does the trick ;)
Instead of .setText(), use .setTag() and .getTag() to attach some value to a View - including a Button - for later retrieval.
These methods are there directly for that kind of purpose.

Access to Java Swing TextField from other class

I have a problem with Java Swing text input. I have a method inputData() in class A and when I call it, the method should wait while user fill TextField input in class B and press ENTER. Finally, the method inputData() should have the text that user wrote. How could I solve it?
class A {
B b = new B();
public A() {
inputData();
}
public char[] inputData() {
// there I would like to get text
// from TextField from class B
}
}
//-------------------------------
class B extends JFrame{
private JTexField input;
public B() {
}
private void inputKeyPressed(KeyEvent e) {
if (e.getKeyCode() == 10) { // pressed ENTER
input.getText()
input.setText(null);
}
}
}
You may not actually want a JTextField. It sounds like you're waiting for a line of input from the user, which should really be a JOptionPane. How to do this is described here:
http://download.oracle.com/javase/tutorial/uiswing/components/dialog.html#input
Basically, JOptionPane.showInputDialog() will cause a window to pop up that contains a text field and OK/Cancel buttons, and if you press enter it will take your input. This eliminates the need for another class.
You'd put it in your inputData() method:
inputData()
{
String input = JOptionPane.showInputDialog(...);
//input is whatever the user inputted
}
If that's not what you're looking for and you want a text field that stays open, perhaps what you really want is a "Submit" button next to your JTextField that allows the user to decide when to submit the text. In that case, you could have:
class B extends JFrame
{
private A myA;
private JTextField input;
private JButton submitButton;
public B()
{
submitButton.addActionListener(new SubmitListener());
}
private class SubmitListener
{
//this method is called every time the submitButton is clicked
public void actionPerformed(ActionEvent ae)
{
myA.sendInput(inputField.getText());
//A will need a method sendInput(String)
}
}
}
TextField? Since it's a Swing project, I hope you mean a JTextField, right? And don't add a KeyListener to it, but rather an ActionListener since these are triggered when the user presses Enter. One way to solve your problem is to give the GUI class (here named B) a public method that will allow outside classes to add an ActionListener to the JTextField. Perhaps you can call it addActionListenerToInput(ActionListener listener). Then Class A can add the listener to B, and the actionPerformed code will be called when enter is pressed.
e.g.,
class A {
B b = new B();
public A() {
//inputData();
b.addActionListenerToInput(new ActionListener() {
public void actionPerformed(ActionEvent e) {
inputActionPerformed(e);
}
});
}
private void inputActionPerformed(ActionEvent e) {
JTextField input = (JTextField) e.getSource();
String text = input.getText();
input.setText("");
// do what you want with the text String here
}
}
//-------------------------------
class B extends JFrame{
private JTextField input;
public B() {
}
public void addActionListenerToInput(ActionListener listener) {
input.addActionListener(listener);
}
}

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