I have a JFrame that has a textfield and a button. It should become visible at the start of program and when I click on the button, It should become invisible and send the text of textfield to another class. but It send nothing and when I click on the button the IDE goes to the debug mode.
public class JframeFoo extends JFrame {
private String username = new String();
public JframeFoo() {
// --------------------------------------------------------------
// Making Frame for login
final JTextField usernameFiled = new JTextField();
this.add(usernameFiled);
JButton signinButton = new JButton();
// ------------------------------------------------------------
signinButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
username = usernameFiled.getText();
setVisible(false);
Main.mainpage.setVisible(true);
}
});
// --------------------------------------------------------------------------
}
public String getuserName() {
return this.username;
}
}
my another class calls Jframe:
System.out.println(JframeFoo.getusername);
Ignoring for a moment that having multiple JFrames jumping out at the user is not a great user interface design, for one object to communicate with another object, it must have a valid reference to the other object. (sorry interrupted by daughter).
So for one JFrame class to get information from the other, it must have a reference to the first object that gets the text, and I don't see you passing that reference, such as in a constructor or setter method.
So for instance if an object of Class1 has information that an object of Class2 needs, then one way to pass it is to give Class2 a reference to the valid instance of Class1, and then have Class2 get the information from the Class1 instance. e.g.,
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import javax.swing.*;
public class ClassMain {
private static void createAndShowGui() {
ClassMain mainPanel = new ClassMain();
JFrame frame = new Class1();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
class Class1 extends JFrame {
private JTextField textfield = new JTextField(10);
public Class1() {
JPanel contentPane = (JPanel) getContentPane();
contentPane.setLayout(new FlowLayout());
add(textfield);
add(new JButton(new AbstractAction("Open Window") {
#Override
public void actionPerformed(ActionEvent arg0) {
Class2 class2 = new Class2(Class1.this);
Class1.this.setVisible(false);
class2.pack();
class2.setVisible(true);
class2.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}));
}
public String getTextfieldText() {
return textfield.getText();
}
}
class Class2 extends JFrame {
private Class1 class1;
private JLabel label = new JLabel("");
public Class2(Class1 class1) {
this.class1 = class1;
label.setText(class1.getTextfieldText());
add(label);
}
}
Related
Hi, I'm new to Java and I have the following problem:
I created a JFrame and I want the JPanel to change when clicking a JButton. That does almost work.The only problem is that the program creates a new window and then there are two windows. One with the first JPanel and one with the second JPanel.
Here is my current code:
first class:
public class Program {
public static void main (String [] args) {
new window(new panel1());
}
}
second class:
import java.awt.Toolkit;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Window extends JFrame {
private static final long serialVersionUID = 1L;
Window(JPanel panel) {
setLocation((int) Toolkit.getDefaultToolkit().getScreenSize().getWidth() / 2 - 200,
(int) Toolkit.getDefaultToolkit().getScreenSize().getHeight() / 2 - 100);
setSize(400, 200);
setTitle("test");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setResizable(false);
setContentPane(panel);
setVisible(true);
}
}
third class:
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JPanel;
public class Panel1 extends JPanel {
private final long serialVersionUID = 1L;
Panel1() {
JButton nextPanelButton = new JButton("click here");
add(nextPanelButton);
ActionListener changePanel = new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
new window(new panel2());
}
};
nextPanelButton.addActionListener(changePanel);
}
}
fourth class:
public class Panel2 extends JPanel {
private static final long serialVersionUID = 1L;
Panel2() {
JLabel text = new JLabel("You pressed the Button!");
add(text);
}
}
But I just want to change the JPanel without opening a new window. Is there a way to do that?
Thanks in advance!
This is a demo
import javax.swing.*;
public class Main {
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
new MainFrame("Title").setVisible(true);
});
}
}
MainFrame.java
import javax.swing.*;
import java.awt.*;
public class MainFrame extends JFrame {
private JPanel viewPanel;
public MainFrame(String title) {
super(title);
createGUI();
}
private void createGUI() {
setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
setLayout(new BorderLayout());
setMinimumSize(new Dimension(600, 480));
viewPanel = new JPanel(new BorderLayout());
add(viewPanel, BorderLayout.CENTER);
showView(new View1(this));
pack();
}
public void showView(JPanel panel) {
viewPanel.removeAll();
viewPanel.add(panel, BorderLayout.CENTER);
viewPanel.revalidate();
viewPanel.repaint();
}
}
View1.java
import javax.swing.*;
import java.awt.*;
public class View1 extends JPanel {
final private MainFrame owner;
public View1(MainFrame owner) {
super();
this.owner = owner;
createGUI();
}
private void createGUI() {
setLayout(new FlowLayout());
add(new JLabel("View 1"));
JButton button = new JButton("Show View 2");
button.addActionListener(event -> {
SwingUtilities.invokeLater(() -> owner.showView(new View2(owner)));
});
add(button);
}
}
View2.java
import javax.swing.*;
import java.awt.*;
public class View2 extends JPanel {
final private MainFrame owner;
public View2(MainFrame owner) {
super();
this.owner = owner;
createGUI();
}
private void createGUI() {
setLayout(new FlowLayout());
add(new JLabel("View 2"));
JButton button = new JButton("Show View 1");
button.addActionListener(event -> {
SwingUtilities.invokeLater(() -> owner.showView(new View1(owner)));
});
add(button);
}
}
First of all, take a look at Java naming conventions, in particular your class names should start with a capitalized letter.
If you want to avoid to open a new window every time you click the button, you could pass your frame object to Panel1 constructor, and setting a new Panel2 instance as the frame content pane when you click the button. There is also no need to pass Panel1 to Window constructor (please note that Window class is already defined in java.awt package, it would be better to avoid a possible name clash renaming your class ApplicationWindow, MyWindow or something else).
You could change your code like this (only relevant parts):
public class Program
{
public static void main (String [] args) {
SwingUtilities.invokeLater (new Runnable () {
#Override public void run () {
new Window ().setVisible (true);
}
};
}
}
class Window extends JFrame
{
// ...
Window () {
// ...
setContentPane(new Panel1 (this));
}
}
class Panel1 extends JPanel
{
// ...
Panel1 (JFrame parent) {
// ...
ActionListener changePanel = new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
parent.setContentPane (new Panel2 ());
}
};
// ...
}
Also note the SwingUtilities's invokeLater call, which is the best way to initialise your GUI in the EDT context (for more info look at this question).
Finally, you could avoid to create a new Panel2 instance every time you click the button, simply by using a CardLayout.
Take a look at the official tutorial.
This is an old post, but it may be useful to answer it in a simplified way. Thanks to mr mcwolf for the first answer.
If we want to make 1 child jframe interact with a main jframe in order to modify its content, let's consider the following case.
parent.java and child.java.
So, in parent.java, we have something like this:
Parent.java
public class Parent extends JFrame implements ActionListener{
//attributes
//here is the class we want to modify
private some_class_to_modify = new some_class_to_modify();
//here is a container which contains the class to modify
private JPanel container = new JPanel();
private some_class = new some_class();
private int select;
//....etc..etc
//constructor
public Parent(){
this.setTitle("My title");
//etc etc
//etc....etc
container.add(some_class_to_modify,borderLayout.CENTER);
}
//I use for instance actionlisteners on buttons to trigger the new JFrame
public void actionPerformed(ActionEvent arg0){
if((arg0.getSource() == source_button_here)){
//Here we call the child class and send the parent's attributes with "this"
Child child = new Child(this);
}
//... all other cases
}//Here is the class where we want to be able to modify our JFrame. Here ist a JPanel (Setcolor)
public void child_action_on_parent(int selection){
this.select = selection;
System.out.println("Selection is: "+cir_select);
if(select == 0) {
//Do $omething with our class to modify
some_class_to_modify.setcolor(Color.yellow);
}
}
In child.java we would have something like this:
public class Child extends JFrame implements ActionListener {
//Again some attributes here
private blabla;
//Import Parent JFrame class
private Parent owner;
private int select_obj=0;
//Constructor here and via Parent Object Import
public Child(Parent owner){
/*By calling the super() method in the constructor method, we call the parent's
constructor method and gets access to the parent's properties and methods:*/
super();
this.owner = owner;
this.setTitle("Select Method");
this.setSize(400, 400);
this.setContentPane(container);
this.setVisible(true);
}
class OK_Button implements ActionListener {
public void actionPerformed(ActionEvent e) {
Object Selection = select;
if(Selection == something) {
select_obj=0;
valid = JOptionPane.showConfirmDialog(null,"You have chosen option 1. Do you want to continue?","Minimum diameter",2);
}
System.out.println("Option is:"+valid);
if(valid == 0) {
setVisible(false);
//Here we can use our herited object to call the child_action_on_parent public class of the Parent JFrame. So it can modify directly the Panel
owner.child_action_on_parent(select_obj);
}
}
}
I have two jframes,
I want to get value from opened another jframe to other opened jframe.
when click jframe1 open button showing jframe2 and type some text in text field and click ok button, text field value want to get jframe1 jlable. how to do this i tried but i can't find a way to do this.
Is this possible ?
Use a callback,
add this code to your project:
Define an interface
public interface ICallbackListener{
void onNewEvent(String msg);
}
add to jframe 2:
private ICallbackListener myListener;
public void addCallback(ICallbackListener myListener){
this.myListener = myListener;
}
...
if(myListener!=null){
myListener.onNewEvent("myMessage");
}
...
add to jframe 1:
private ICallbackListener myListener;
ICallbackListener i = new ICallbackListener() {
#Override
public void onNewEvent(String msg) {
// TODO Auto-generated method stub
}
};
public void setCallback( ){
jframe2.addCallback(myListener);
}
now, every thime the jframe2 call the interface method you will get asynchronous a call to the TODO label in the jframe1
Try This
import java.awt.FlowLayout;
import javax.swing.*;
import java.awt.event.*;
class TestFrameExample extends JFrame implements ActionListener{
static JLabel label ;
public static TestFrameExample test;
TestFrameExample()
{
JPanel panel = new JPanel();
panel.setLayout(new FlowLayout());
label = new JLabel("This is a label!");
JButton button = new JButton("Open");
button.setText("Press me");
button.addActionListener(this);
panel.add(label);
panel.add(button);
add(panel);
setSize(300, 300);
setLocationRelativeTo(null);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
}
public void actionPerformed(ActionEvent a)
{
new TestFrameExample1();
}
public static void main(String s[]) {
test=new TestFrameExample();
}
}
class TestFrameExample1 extends JFrame implements ActionListener {
JTextField t;
TestFrameExample test;
public TestFrameExample1()
{
setSize(300, 300);
setLocationRelativeTo(null);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
setLayout(null);
t=new JTextField();
t.setBounds(100,20,150,20);
JButton button=new JButton("oK");
button.setBounds(100,50,100,30);
button.addActionListener(this);
add(t);
add(button);
}
public void actionPerformed(ActionEvent a)
{
test.label.setText(t.getText());
}
}
create a method that takes jframe1 in the jframe2
in the open button action event create a object from jframe2 and call that method that take jframe1.
so when u click Ok button in the jframe2 pass that text field value to the jframe1 object (that u passed to the jframe2) via a methdo
public class jframe1 {
public void actionPerformed(ActionEvent a){
jfame2 jf2 = new jframe2();
jf2.setJframe1(this);
}
public void updateLable(String value){
lblIdk.setText(value);
}
}
public class jframe2 {
private jframe1 jf1;
public void setJframe1(jframe1 jf1){
this.jf1 = jf1;
}
public void actionPerformed(ActionEvent a){
this.jf1.updateLable(txtidk.getText());
}
}
To be short, I create a class Something witch have a function with a JFrame where I have a label and a button on it. On the button I have an addActionListener(new changeLabel()).
I did class changeLabel in the src package for the listener but when I start the application and I click the button throw an NullPointerException on the changeLabel at
nameLabel.setText("Name changed");
line. I want to mention that if I create this listener class in Something class, work perfectly.
I don't know why throw null exception because the label is initialized firstly and after that, the button just want to change the text.
I tryed to make a getFunction, to call that label, I tryed with object Something, with object changeLabel etc... but doesn't work.
Here is some code
package trying;
import javax.swing.*;
import java.awt.BorderLayout;
import java.awt.event.*;
public class Something {
JFrame frame;
JLabel changeName;
JButton button;
public void gui(){
frame = new JFrame();
frame.setSize(200, 200);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//is just an example
changeName = new JLabel("Stefan");
//is just an example
button = new JButton("Change");
button.addActionListener(new changeLabel());
frame.getContentPane().add(changeName, BorderLayout.NORTH);
frame.getContentPane().add(button, BorderLayout.SOUTH);
frame.setVisible(true);
}
public static void main(String args[]){
new Something().gui();
}
}
The listener class
package trying;
import java.awt.event.*;
public class changeLabel extends Something implements ActionListener{
#Override
public void actionPerformed(ActionEvent e) {
changeName.setText("Andrei");
}
}
How can I solve this problem?
The problem is that because the changeLabel class extends Something, it will contain it's own changeName variable which is not initialized == null.
You can:
make the changeLabel implementation private class of Something (good practice) or
pass the JLabel to its constructor.
In both ways changeLabel should not extend Something.
Code Sample #1:
public class Something {
JFrame frame;
JLabel changeName;
JButton button;
public void gui(){
frame = new JFrame();
frame.setSize(200, 200);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//is just an example
changeName = new JLabel("Stefan");
//is just an example
frame.getContentPane().add(changeName, BorderLayout.NORTH);
button = new JButton("Change");
button.addActionListener(new changeLabel());
frame.getContentPane().add(button, BorderLayout.SOUTH);
frame.setVisible(true);
}
public static void main(String args[]){
new Something().gui();
}
class changeLabel implements ActionListener{
#Override
public void actionPerformed(ActionEvent e) {
changeName.setText("Andrei");
}
}
}
Code Sample #2:
public class Something {
...
public void gui() {
...
button.addActionListener(new changeLabel(changeName));
}
}
public class changeLabel implements ActionListener {
private final JLabel label;
public changeLabel(JLabel label) {
this.label = label;
}
#Override
public void actionPerformed(ActionEvent e) {
label.setText("Andrei");
}
}
I am attempting a very simple form designed to take user input into a JTextField and show that same input via a pop up dialog.
I can hardcode the JTextField to have a preset number using setText(). If I do this, my program works flawlessly.
However, when I leave the field blank and try getText() to show the text in the pop up dialog, I either get an empty pop up frame, or I get an 'empty string' exception (I am attempting to parse String to Double.)
package buttontest;
import java.awt.*;
import java.awt.event.ActionListener;
import java.awt.event.ComponentEvent;
import javax.swing.*;
import java.awt.event.ActionEvent;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
public class ButtonTest
{
public static void main(String[] args)
{
ButtonFrame frame = new ButtonFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
class ButtonFrame extends JFrame
{
#SuppressWarnings("LeakingThisInConstructor")
public ButtonFrame()
{
setTitle("SunStream Loan Calculator v2.0");
setSize(900,900);
ButtonPanel panel = new ButtonPanel();
panel.add(new JLabel("Enter your loan amount:"));
loanAmt = new JTextField(40);
panel.add(loanAmt);
add(panel,BorderLayout.CENTER);
}
public JTextField loanAmt;
class ButtonPanel extends JPanel implements ActionListener
{
private Component frame;
public ButtonPanel()
{
final JButton b2 = new JButton("Calculate");
add(b2, BorderLayout.SOUTH);
b2.setActionCommand("calculate");
b2.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e)
{
ButtonFrame bf = new ButtonFrame();
if("calculate".equals(e.getActionCommand()))
{
JOptionPane.showMessageDialog(frame, bf.loanAmt.getText());
}
}
});
}
#Override
public void actionPerformed(ActionEvent ae) {
throw new UnsupportedOperationException("Not supported yet.");
}
}
}
Any help would be greatly appreciated. I am researching using a KeyListener or KeyEvent but I don't quite understand it well enough.
You're creating a "shadow" ButtonFrame variable inside of the b2's ActionListener. Yes the bf variable refers to a ButtonFrame object which is of the same class as the displayed ButtonFrame object, but it refers to a completely distinct and non-visualized object. The key to a solution is to get the text from the ButtonFrame object that is actually displayed, and this can be obtained from within an inner class via the ButtonFrame.this construct:
b2.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
//!! ButtonFrame bf = new ButtonFrame();
if ("calculate".equals(e.getActionCommand())) {
//!! note use of ButtonFrame.this:
JOptionPane.showMessageDialog(frame, ButtonFrame.this.loanAmt.getText());
}
}
});
Next consider using public getters rather than accessing fields such as the JTextField directly. This reduces the chances of the code causing side effects, such as changing the properties of the JTextField object inadvertently.
For instance (changes denoted by //!! comment):
import java.awt.*;
import java.awt.event.ActionListener;
import javax.swing.*;
import java.awt.event.ActionEvent;
public class ButtonTest {
public static void main(String[] args) {
ButtonFrame frame = new ButtonFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
class ButtonFrame extends JFrame {
private JTextField loanAmt; // !! Make field private
#SuppressWarnings("LeakingThisInConstructor")
public ButtonFrame() {
setTitle("SunStream Loan Calculator v2.0");
setSize(900, 900);
ButtonPanel panel = new ButtonPanel();
panel.add(new JLabel("Enter your loan amount:"));
loanAmt = new JTextField(40);
panel.add(loanAmt);
add(panel, BorderLayout.CENTER);
}
// !! create a public method to get JTextField's text
// !! without exposing the JTextField itself.
public String getLoanAmtText() {
return loanAmt.getText();
}
class ButtonPanel extends JPanel implements ActionListener {
private Component frame;
public ButtonPanel() {
final JButton b2 = new JButton("Calculate");
add(b2, BorderLayout.SOUTH);
b2.setActionCommand("calculate");
b2.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// !! ButtonFrame bf = new ButtonFrame();
if ("calculate".equals(e.getActionCommand())) {
//!! call public method on ButtonFrame object
JOptionPane.showMessageDialog(frame,
ButtonFrame.this.getLoanAmtText());
}
}
});
}
#Override
public void actionPerformed(ActionEvent ae) {
throw new UnsupportedOperationException("Not supported yet.");
}
}
}
The only way you can access your loanAmt is through ButtonPanel itself. Because you add loanAmt to this button right ?
So, if you want access loanAmt. You must get all component on this button panel. This is my psudeo code howto accessing your loanAmt from ButtonPanel class.
b2.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
ButtonFrame bf = new ButtonFrame();
if("calculate".equals(e.getActionCommand())) {
// Get all component
java.awt.Component[] componentList = this.getComponents();
JTextField txtField;
String value;
for (int i = 0; i < componentList.length; i++) {
if (componentList[i].getClass().getName().equals("javax.swing.JTextField")) {
txtField = (JTextField) componentList[i];
value = textField.getText();
}
}
if (value != null) JOptionPane.showMessageDialog(frame, value);
}
}
});
I Googled for a lot, and no solutions found. I think there shall be java masters to help me out ...
This is my initialize method:
private void initialize() {
this.setSize(750, 480);
this.setContentPane(getJContentPane());
this.setTitle("Registration");
JPanel topPane = new TopPane();
this.getContentPane().add(topPane,BorderLayout.PAGE_START);
cards=new JPanel(new CardLayout());
cards.add(step0(),"step0");
cards.add(step1(),"step1");
cards.add(step2(),"step2");
this.getContentPane().add(cards,BorderLayout.CENTER);
}
public JPanel step2(){
EnumMap<DPFPFingerIndex,DPFPTemplate> template = new EnumMap<DPFPFingerIndex, DPFPTemplate>(DPFPFingerIndex.class);
JPanel enrol = new Enrollment(template,2);
return enrol;
}
public JPanel step0(){
JPanel userAgree = new UserAgreement();
return userAgree;
}
public JPanel step1(){
JPanel userInfo = new UserInformation();
return userInfo;
}
public JPanel getCards(){
return cards;
}
This, is the method at another step0 JPanel:
jButtonAgree.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent e) {
Registration reg = new Registration();
LayoutManager cards = reg.getCards().getLayout();
((CardLayout) cards).show(reg.getCards(),"step1");
}
});
No reation at all, i tried revalidate, repaint and other staff... doesn't work ... any one got any soution here!
It's all about exposing the right methods and constant Strings to the outside world to allow the class to swap views itself. For example, give your first class a private CardLayout field called cardlayout and a private JPanel field called cards (the card holder JPanel), and some public String constants that are used to add your card JPanels to the cards container. Also give it a public method, say called public void swapView(String key) that allows outside classes to swap cards... something like so:
// code corrected
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Registration extends JPanel {
// use these same constants as button texts later
private static final Dimension PREF_SIZE = new Dimension(450, 300);
public static final String USER_AGREEMENT = "User Agreement";
public static final String USER_INFO = "User Information";
public static final String ENROLLMENT = "Enrollment";
// we'll extract them from this array
public static final String[] KEY_TEXTS = {USER_AGREEMENT, USER_INFO, ENROLLMENT};
private CardLayout cardlayout = new CardLayout();
private JPanel cards = new JPanel(cardlayout);
public Registration() {
cards.add(createUserAgreePanel(), USER_AGREEMENT);
cards.add(createUserInfoPanel(), USER_INFO);
cards.add(createEnrollmentPanel(), ENROLLMENT);
setLayout(new BorderLayout());
add(cards, BorderLayout.CENTER);
}
#Override
public Dimension getPreferredSize() {
return PREF_SIZE;
}
private JPanel createEnrollmentPanel() {
JPanel enrol = new JPanel();
enrol.add(new JLabel("Enrollment"));
return enrol;
}
private JPanel createUserAgreePanel() {
JPanel userAgree = new JPanel();
userAgree.add(new JLabel("User Agreement"));
return userAgree;
}
private JPanel createUserInfoPanel() {
JPanel userInfo = new JPanel();
userInfo.add(new JLabel("User Information"));
return userInfo;
}
public void swapView(String key) {
cardlayout.show(cards, key);
}
}
Then an outside class can swap views simply by calling the swapView on the visualized instance of this class, passing in the appropriate key String such as in this case CardTest.USER_INFO to show the user info JPanel.
Now you have a problem with this bit of code where I indicate by comment:
jButtonAgree.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent e) {
Registration reg = new Registration(); // **** HERE *****
LayoutManager cards = reg.getCards().getLayout();
((CardLayout) cards).show(reg.getCards(),"step1");
}
});
On that line you're creating a new Registration object, probably one that is completely unrelated to the one that is visualized on the GUI, and so calling methods on this new object will have absolutely no effect on the currently viewed gui. YOu need instead to get a reference to the viewed Registration object, perhaps by giving this class a getRegistration method, and then call its methods, like so:
class OutsideClass {
private Registration registration;
private JButton jButtonAgree = new JButton("Agree");
public OutsideClass() {
jButtonAgree.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// make sure registration reference has been obtained first!
if (registration != null) {
registration.swapView(Registration.USER_AGREEMENT);
}
}
});
}
// here I allow the calling class to pass a reference to the visualized
// Registration instance.
public void setRegistration(Registration registration) {
this.registration = registration;
}
}
For example:
#SuppressWarnings("serial")
class ButtonPanel extends JPanel {
private Registration registration;
public ButtonPanel() {
setLayout(new GridLayout(1, 0, 10, 0));
// go through String array making buttons
for (final String keyText : Registration.KEY_TEXTS) {
JButton btn = new JButton(keyText);
btn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (registration != null) {
registration.swapView(keyText);
}
}
});
add(btn);
}
}
public void setRegistration(Registration registration) {
this.registration = registration;
}
}
and the MainClass that drives this all
class MainClass extends JPanel {
public MainClass() {
Registration registration = new Registration();
ButtonPanel buttonPanel = new ButtonPanel();
buttonPanel.setRegistration(registration);
buttonPanel.setBorder(BorderFactory.createTitledBorder("Button Panel"));
registration.setBorder(BorderFactory.createTitledBorder("Registration Panel"));
setLayout(new BorderLayout());
add(registration, BorderLayout.CENTER);
add(buttonPanel, BorderLayout.SOUTH);
}
private static void createAndShowUI() {
JFrame frame = new JFrame("Registration");
frame.getContentPane().add(new MainClass());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
createAndShowUI();
}
});
}
}