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Frame does not open correctly at calculator program in JAVA although it compiled correctly

This my code :
import java.awt.event.*;
import javax.swing.*;
class CalcFrame extends JFrame {
private JButton btnClear;
private JButton btnEquals;
private JLabel lblDisplay;
private JButton[] btnOps = new JButton[4];
public CalcFrame(){
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
this.setBounds(122,444 ,322,123);
}
}
following image shows, the result that i have :
frame image

As I suspected, and #jchamp pointed out in the comments, your main code reads:
public static void main(String[] args) {
JFrame mx = new JFrame();
mx.setVisible();
}
The code in the CalcFrame constructor is not executed, so any setBounds() or setSize() call is not executed and will therefore have no effect. This also explains the close button not terminating the application, because the setDefaultCloseOperation is also never called.
Instead, create and show your CalcFrame:
public static void main(String[] args) {
CalcFrame mx = new CalcFrame();
mx.setVisible();
}

GUI close issue?

I have a program which displays two buttons and changes the image of one of the buttons on roll over. I am getting an error on my
press.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
part, And it looks like this: The method setDefaultCloseOperation(int) is undefined for the type ButtonClass. Even with the exit on close commented out there are more errors, please help.
Main class (with error):
package Buttons;
import javax.swing.JFrame;
public class Main_buttons{
public static void main(String[] args) {
ButtonClass press = new ButtonClass();
press.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
press.setSize(300,200);
press.setVisible(true);
}
}
ButtonClass class:
package Buttons;
import java.awt.FlowLayout; //layout proper
import java.awt.event.ActionListener; //Waits for users action
import java.awt.event.ActionEvent; //Users action
import javax.swing.JFrame; //Window
import javax.swing.JButton; //BUTTON!!!
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JOptionPane; //Standard dialogue box
public class ButtonClass extends JButton {
private JButton regular;
private JButton custom;
public ButtonClass() { // Constructor
super("The title"); // Title
setLayout(new FlowLayout()); // Default layout
regular = new JButton("Regular Button");
add(regular);
Icon b = new ImageIcon(getClass().getResource("img.png"));
Icon x = new ImageIcon(getClass().getResource("swag.png"));
custom = new JButton("Custom", b);
custom.setRolloverIcon(x); //When you roll over the button that says custom the image will change from b to x
add(custom);
Handlerclass handler = new Handlerclass();
regular.addActionListener(handler);
custom.addActionListener(handler);
}
private class Handlerclass implements ActionListener { // This class is inside the other class
public void actionPerformed(ActionEvent eventvar) { // This will happen
// when button is
// clicked
JOptionPane.showMessageDialog(null, String.format("%s", eventvar.getActionCommand()));//Opens a new window with the name of the button
}
}
}
I have searched everywhere for this problem and found nothing. Please tell me how to resolve this issue about exiting my window.
Thanks!

You're a little confused as you're creating a class that extends JButton, and calling setVisible(true) on it as if it were a top-level window such as a JFrame or JDialog, and that doesn't make sense. Since it isn't a top-level window it also makes sense to not have a default close operation or understand what that means.
I suggest that you call this method only on top-level windows such as on a JFrame or JDialog and the like. As a side recommendation, I usually avoid setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); and instead more often do setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); which gives it a little more flexibility.
Edit: actually, just change your class to extends JFrame not extends JButton.
Make sure your image path to your resources is correct. For example:

that method is defined for JFrame, not JButton. You're calling it on an instance of a class that extends JButton

The JFrame.Exit_on_close must be used in a JFrame, and you are extending from JButton.
To set a JButton to close a JFrame its something like this.
public class MyClass extends JFrame implements ActionListener{
private JButton button = new JButton("Button");
private JPanel panel = new JPanel();
public static void main(String args[]) {
new MyClass();
}
public MyClass() {
setSize(300, 300);
button.addActionListener(this);
panel.add(button);
add(panel);
setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
this.dispose();
}
}

Using Keybinding

I'm doing some very basic coding, just trying to learn the basic concepts behind keybinding. It all seems very straightforward but there's something wrong with my logic or structure that is keeping my code from executing the way I want it to.
Here is my code
public class Board {
ButtonListener buttonlistener;
EnterAction enterAction;
public Board(){
JFrame skeleton = new JFrame();
skeleton.setDefaultCloseOperation(EXIT_ON_CLOSE);
skeleton.setVisible(true);
skeleton.setSize(400, 400);
buttonlistener = new ButtonListener();
enterAction = new EnterAction();
JPanel panel = new JPanel();
panel.setBackground(Color.BLACK);
JButton button = new JButton("button");
button.addActionListener(buttonlistener);
panel.add(button);
skeleton.add(panel);
panel.getInputMap().put(KeyStroke.getKeyStroke("s"), "doEnterAction");
panel.getActionMap().put("doEnterAction", enterAction);
}
public class ButtonListener implements ActionListener{
#Override
public void actionPerformed(ActionEvent arg0) {
System.out.println("button pressed");
}
}
public class EnterAction extends AbstractAction{
#Override
public void actionPerformed(ActionEvent e) {
System.out.println("enter pressed");
}
}
public static void main(String[] args){
new Board();
}
So, it should be pretty simple. As you can see I'm just trying to make it print out "enter pressed" whenever you press enter, but it isn't printing out anything (unless you click the button also shown in the code above). Also, in eclipse, the EnterAction class is underlined in yellow, I think it may not be being called right, but I don't know why it wouldn't be.
Any help is appreciated, thanks.

Change
panel.getInputMap().put(KeyStroke.getKeyStroke("s"), "doEnterAction");
To
panel.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke("S"), "doEnterAction");
Also
skeleton.setDefaultCloseOperation(EXIT_ON_CLOSE);
the parameter must be JFrame.EXIT_ON_CLOSE or just put number 3.

The immediate issue I can see is with the following statement
panel.getInputMap().put(KeyStroke.getKeyStroke("s"), "doEnterAction");
KeyStroke.getKeyStroke("s") is going to return null. The requirements for the String passed to this method are very particular and not well documented (IMHO).
You could use KeyStroke.getKeyStroke("S") instead, but I prefer to use KeyStroke.getKeyStroke(KeyEvent.VK_S, 0) as there is no chance of ambiguity in the statement.
I would also recommend that you define the focus boundaries as well for the input map...
Instead of panel.getInputMap(), try using panel.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW) to ensure that the key event will be triggered if the window is focused
Take a look at JComponent#getInputMap for more details.
If you haven't already done so, you should also take a look at How to use Key Bindings

I think Azad and MadProgrammer are correct, I only had to make one more simple change in addition to what they recommended to get the program running. I have numbered the three items for you as a comment in the code: (copy and paste and you are good to go).
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.KeyStroke;
public class Board {
ButtonListener buttonlistener;
EnterAction enterAction;
public Board() {
JFrame skeleton = new JFrame();
//Change #1 below
skeleton.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
skeleton.setVisible(true);
skeleton.setSize(400, 400);
buttonlistener = new ButtonListener();
enterAction = new EnterAction();
JPanel panel = new JPanel();
panel.setBackground(Color.BLACK);
JButton button = new JButton("button");
button.addActionListener(buttonlistener);
panel.add(button);
skeleton.add(panel);
//Change #2 below
panel.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(
KeyStroke.getKeyStroke("S"), "doEnterAction");
panel.getActionMap().put("doEnterAction", (Action) enterAction);
}
public class ButtonListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent arg0) {
System.out.println("button pressed");
}
}
public class EnterAction extends AbstractAction {
#Override
public void actionPerformed(ActionEvent e) {
System.out.println("enter pressed");
}
}
public static void main(String[] args) {
new Board();
}
//Change #3 below
}
here is the screenshot:

calling a JPanel stand alone class from another class to be display when a button is click [duplicate]

I have a class that extends JFrame, and it has a BorderLayout. It has two private instance variables of type JPanel. They represent panels of buttons and are called flipButton and confidenceButtons. When you click on the button, the panel of buttons is replaced by the other panel of buttons. That is, if you click on a button in flipButton, flipButton is replaced by confidenceButtons. I tried to do it like this:
private class FlipListener implements ActionListener{
public void actionPerformed(ActionEvent e){
remove(flipButton);
add(confidenceButtons,BorderLayout.SOUTH);
validate();
...
}
}
private class ColorListener implements ActionListener{
...
public void actionPerformed(ActionEvent e){
...
remove(confidenceButtons);
add(flipButton,BorderLayout.SOUTH);
validate();
}
}
The buttons in flipButton have FlipListeners and the ones in confidenceButtons have ColorListeners. When the program is run, clicking on a button will remove the panel, but nothing is added to replace it. What am I doing wrong?
EDIT
CardLayout turned out to be a simple and easy solution. It turns out that the above code does work; the problem was a typo in another section of my code. >.< However, I've always had trouble using these methods, and CardLayout, I find, simplifies it for me. Thanks.

Use a CardLayout, as shown here.

revalidate() + repaint() should be trick, example here
EDIT:
feel that you have got problem with that, examples for that here and here and again example by trashgod, feel free to built your question based on code again
another way is look at excelent example added by Andrew Thompson :-) +1

try using getContentPane() to call remove() ,add() methods ect..:
getContentPane().remove(flipButton);
getContentPane().add(confidenceButtons,BorderLayout.SOUTH);
getContentPane().revalidate();
getContentPane().repaint();
Edit:
this code bellow work for me:
import java.awt.BorderLayout;
import java.awt.HeadlessException;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Frame extends JFrame {
JPanel flipButton =new JPanel();
JPanel confidenceButtons =new JPanel();
public Frame() throws HeadlessException {
super();
this.setLayout(new BorderLayout());
JButton b1=new JButton("flip");
b1.addActionListener(new FlipListener());
flipButton.add(b1);
JButton b2=new JButton("color");
b2.addActionListener(new ColorListener());
confidenceButtons.add(b2);
this.getContentPane().add(flipButton,BorderLayout.SOUTH);
this.setSize(250,250);
this.pack();
this.setVisible(true);
}
private class FlipListener implements ActionListener{
public void actionPerformed(ActionEvent e){
remove(flipButton);
add(confidenceButtons,BorderLayout.SOUTH);
validate();
repaint();
}
}
private class ColorListener implements ActionListener{
public void actionPerformed(ActionEvent e){
remove(confidenceButtons);
add(flipButton,BorderLayout.SOUTH);
validate();
repaint();
}
}
/**
* #param args
*/
public static void main(String[] args) {
new Frame();
}
}

Java GUI won't display JLabel

I would like to create a simple GUI in Java. I know the basics of creating JLabel, etc. However, I cannot find why my JLabel is not displayed on the screen. Here is my code:
package test;
import java.awt.Color;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.event.*;
import javax.swing.*;
public class A1Panel extends JPanel implements ActionListener {
JLabel firstInt;
public void init() {
makeComponents();
makeLayout();
}
private void makeComponents() {
firstInt = new JLabel("First argument");
firstInt.setFont(new Font("Helvetica", Font.BOLD, 16));
firstInt.setBackground(Color.lightGray);
firstInt.setVisible(true);
firstInt.setHorizontalAlignment(SwingConstants.CENTER);
}
private void makeLayout() {
add(firstInt);
}
public void actionPerformed(ActionEvent e) {
}
}
I then add my JPanel to my JFrame using a different class called GUI:
import test.A1Panel;
public class GUI {
public static void main(String[] args) {
JFrame frame = new JFrame("Testing GUI");
frame.setLayout( new GridLayout(1,3));
JPanel panel = new A1Panel();
panel.setBorder( BorderFactory.createRaisedBevelBorder() );
frame.add( panel);
frame.setSize(800,600);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
frame.pack();
}
}
When I hit compile, what I get is a simple frame with three empty panels. I do not understand why my JLabel is not in the first panel since I have added it to my frame. Am I missing something?

The frame is not empty, the panel is. Nowhere in your code do I see a call to the methods init() or makeComponents(). In fact, I would turn your init() method into a constructor, like so:
public A1Panel() {
makeComponents();
makeLayout();
}
Another alternative to this would be to call panel.init() after declaring JPanel panel = new A1Panel()

After you instance A1Panel, you haven't called A1Panel.init()
I would suggest removing init() and adding all the code to the constructor of A1Panel. If, however, you wanted to keep the init() function, you would want to call it after JPanel panel = new A1Panel()

The code to add the label was not actually called in the main, was it? So look carefully, when is init actually called?
Look at the
private void makeLayout()
method.

If I replace public void init() by A1Panel(), it does the job. Thank you for your help.