I need a running order of pages 1-5 pages. I am using the card layout to navigate between each page after entering data on each page. The navigation to the next page works via an Action Listener on each text field.
My question is how do I pass the input from each card/page to the next? I can System.out.println each TextFeilds data. But I can't grab this information in the next card/action listener. The reason I need this to happen is I'd like to compare the strings of each page and also display a label of page 1's input on page/card2.
I apologize in advance for the massive block of code... Most of you will recognise most of this code anyway as it's copied from the CardLayout sample java code. I have just added two cards just now until I get the basics of passing variables back and fourth.
All help is appreciated even a small push the the right direction.
import java.awt.*;
import java.awt.CardLayout;
import java.awt.Dimension;
import java.awt.event.*;
import java.sql.Connection;
import java.sql.DriverManager;
import java.util.Scanner;
import javax.swing.*;
public class CardLayoutDemo implements ItemListener {
JPanel cards; //a panel that uses CardLayout
final static String TEXTPANEL = "Card1 with text";
final static String TEXTPANEL2 = "Card with JTextField";
public void addComponentToPane(Container pane) {
//Put the JComboBox in a JPanel to get a nicer look.
JPanel comboBoxPane = new JPanel(); //use FlowLayout
String comboBoxItems[] = { TEXTPANEL, TEXTPANEL2};
JComboBox cb = new JComboBox(comboBoxItems);
cb.setEditable(false);
cb.addItemListener(this);
comboBoxPane.add(cb);
//Create the "cards".
JPanel card1 = new JPanel();
JTextField jtf=new JTextField("", 40);
jtf.setSize(40, 10);
card1.add(jtf);
JLabel lab1 = new JLabel("Page1 Text", JLabel.LEFT);
card1.add(lab1 = new JLabel("Page1"));
JPanel card2 = new JPanel();
JTextField jtf2=new JTextField("", 40);
jtf2.setSize(40, 10);
card2.add(jtf2);
JLabel lab2 = new JLabel("Page2 Text", JLabel.LEFT);
card2.add(lab2 = new JLabel("Page2 "));
//Create the panel that contains the "cards".
cards = new JPanel(new CardLayout());
cards.add(card1, TEXTPANEL);
cards.add(card2, TEXTPANEL2);
pane.add(cards, BorderLayout.CENTER);
jtf.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e)
{
String getText1 = jtf.getText();
System.out.println("PAGE1 ");
System.out.println(getText1);
CardLayout cl = (CardLayout)(cards.getLayout());
cl.show(cards, TEXTPANEL2);
jtf2.requestFocus();
jtf2.requestFocusInWindow();
}
//JOptionPane.showMessageDialog(null,"Action Listener is working");
});
//PAGE2
jtf2.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e)
{
String getText2 = jtf2.getText();
System.out.println("PAGE2 ");
System.out.println(getText2);
CardLayout cl = (CardLayout)(cards.getLayout());
cl.show(cards, TEXTPANEL);
jtf.requestFocus();
jtf.requestFocusInWindow();
jtf.setText("");
}
});
}//ADD COMPONENT TO PANE
public void itemStateChanged(ItemEvent evt) {
CardLayout cl = (CardLayout)(cards.getLayout());
cl.show(cards, (String)evt.getItem());
// String getLoginUser1 = jtf.getText();
//System.out.println(getLoginUser1);
}
/**
* Create the GUI and show it. For thread safety,
* this method should be invoked from the
* event dispatch thread.
*/
private static void createAndShowGUI() {
//Create and set up the window.
JFrame frame = new JFrame("CardLayoutDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setPreferredSize(new Dimension(600, 300));
JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the content pane.
CardLayoutDemo demo = new CardLayoutDemo();
demo.addComponentToPane(frame.getContentPane());
//Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
/* Use an appropriate Look and Feel */
try {
//UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel");
} catch (UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
} catch (IllegalAccessException ex) {
ex.printStackTrace();
} catch (InstantiationException ex) {
ex.printStackTrace();
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
}
/* Turn off metal's use of bold fonts */
UIManager.put("swing.boldMetal", Boolean.FALSE);
//Schedule a job for the event dispatch thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
Here is another view on the problem. You could create some kind of cards manager and hold all required info inside of it. Here is an example:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.ArrayList;
public class CardLayoutDemo implements ItemListener {
private static class QuizManager {
final java.util.List<String> quizData = new ArrayList<>();
final java.util.List<JPanel> cards = new ArrayList<>();
final JPanel rootView;
public QuizManager(JPanel root){
rootView = root;
}
private JPanel createQuizPanel(String pageText, final int index) {
JPanel card = new JPanel();
JTextField jtf=new JTextField("", 40);
jtf.setSize(40, 10);
JLabel prev = new JLabel("", JLabel.LEFT);
card.add(prev);
card.add(jtf);
card.add(new JLabel(pageText, JLabel.LEFT));
jtf.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
QuizManager.this.onCardSubmited(card, index, jtf.getText());
}
});
card.addComponentListener(new ComponentAdapter() {
#Override
public void componentShown(ComponentEvent e) {
super.componentShown(e);
jtf.requestFocus();
jtf.requestFocusInWindow();
String text = QuizManager.this.getPrevStringFor(index);
if (text != null) {
prev.setText(text);
}
}
});
return card;
}
private String getPrevStringFor(int index) {
if (index == 0) return null;
return quizData.get(index-1);
}
private String buildPanelName(int index) {
return String.format("card-%d", index);
}
public QuizManager addCard(String title) {
int index = cards.size();
quizData.add(null);//not set yet, just allocating
JPanel card = createQuizPanel(title, index);
cards.add(card);//this array looks like redundant
rootView.add(card, buildPanelName(index));
return this;
}
private void showCard(int index) {
CardLayout cl = (CardLayout) (rootView.getLayout());
cl.show(rootView, buildPanelName(index));
}
public void show() {
showCard(0);
}
public void onCardSubmited(JPanel card, int cardIndex, String text) {
System.out.println("page " + cardIndex);
System.out.println("text : " + text);
quizData.set(cardIndex, text);
if (cardIndex < cards.size() - 1) {
showCard(cardIndex + 1);
} else {
System.out.println("WE FINISHED");
//add finalazing code here
}
}
}
JPanel cardsRoot;
public void addComponentToPane(Container pane) {
cardsRoot = new JPanel(new CardLayout());
QuizManager manager = new QuizManager(cardsRoot)
.addCard("First page")
.addCard("Second page")
.addCard("Third card")
.addCard("Forth card");
pane.add(cardsRoot, BorderLayout.CENTER);
manager.show();
}
public void itemStateChanged(ItemEvent evt) {
CardLayout cl = (CardLayout)(cardsRoot.getLayout());
cl.show(cardsRoot, (String)evt.getItem());
}
/**
* Create the GUI and show it. For thread safety,
* this method should be invoked from the
* event dispatch thread.
*/
private static void createAndShowGUI() {
//Create and set up the window.
JFrame frame = new JFrame("CardLayoutDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setPreferredSize(new Dimension(600, 300));
JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the content pane.
CardLayoutDemo demo = new CardLayoutDemo();
demo.addComponentToPane(frame.getContentPane());
//Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
/* Use an appropriate Look and Feel */
try {
//UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel");
} catch (UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
} catch (IllegalAccessException ex) {
ex.printStackTrace();
} catch (InstantiationException ex) {
ex.printStackTrace();
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
}
/* Turn off metal's use of bold fonts */
UIManager.put("swing.boldMetal", Boolean.FALSE);
//Schedule a job for the event dispatch thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
Take a look how easy would be to create many of cards.
You've got the variable declaration of key components buried within the addComponentToPane(...) method, limiting their scope to this method only, preventing you from getting the information you need. While the canonical solution for this sort of problem is to use an model-view-controller or MVC type pattern so that the model (the underlying program logic and data) is extracted out of the view (the GUI), you can do a quick and dirty solution just by giving your variables private class scope.
For instance, if the JTextField was called textField and was held in a JPanel that acts as a "card", say called cardPanel, you could create a class that looked something like so:
public class CardPanel extends JPanel {
// constants to give the GUI a bigger size
private static final int PREF_W = 300;
private static final int PREF_H = 100;
// our key JTextField declared at class level
private JTextField textField = new JTextField(20);
// a JLabel to display the previous cardpanel's text
private JLabel label = new JLabel(" ");
// create the JPanel
public CardPanel(String name) {
setName(name);
setBorder(BorderFactory.createTitledBorder("Panel " + name));
JPanel labelPanel = new JPanel(new FlowLayout(FlowLayout.LEADING));
labelPanel.add(new JLabel("Prior Card's Word: "));
labelPanel.add(label);
setLayout(new BorderLayout());
add(textField, BorderLayout.PAGE_START);
add(labelPanel, BorderLayout.CENTER);
}
// have to jump through this hoop if we want to JTextField to
// have focus when a card is swapped
public void setFocusOnTextField() {
textField.requestFocusInWindow();
textField.selectAll();
}
// to make our GUI larger
#Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(PREF_W, PREF_H);
}
// allow outside classes to add a listener to the JTextField
public void addActionListener(ActionListener listener) {
textField.addActionListener(listener);
}
// allow outside classes to get text from the text field
public String getTextFieldText() {
return textField.getText();
}
// allow outside classes to put text into the JLabel
public void setLabelText(String text) {
label.setText(text);
}
}
And then we could use it like so:
public class MyCardLayoutDemo extends JPanel {
private static final String[] NAMES = {"One", "Two", "Three", "Four"};
private Map<String, CardPanel> namePanelMap = new HashMap<>();
private CardLayout cardLayout = new CardLayout();
private int nameIndex = 0;
public MyCardLayoutDemo() {
setLayout(cardLayout);
MyListener listener = new MyListener();
for (String name : NAMES) {
CardPanel cardPanel = new CardPanel(name);
cardPanel.addActionListener(listener);
add(cardPanel, name);
namePanelMap.put(name, cardPanel);
}
}
private class MyListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
// get the current CardPanel
String name = NAMES[nameIndex];
CardPanel currentCard = namePanelMap.get(name);
// advance the name index to get the next CardPanel
nameIndex++;
nameIndex %= NAMES.length;
name = NAMES[nameIndex];
CardPanel nextCard = namePanelMap.get(name);
// get text from current CardPanel
String text = currentCard.getTextFieldText();
nextCard.setLabelText(text); // and put it into next one
// swap cards
cardLayout.show(MyCardLayoutDemo.this, name);
nextCard.setFocusOnTextField();
}
}
private static void createAndShowGui() {
MyCardLayoutDemo mainPanel = new MyCardLayoutDemo();
JFrame frame = new JFrame("My CardLayout Demo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> createAndShowGui());
}
}
Related
I am using a self made toolbar to navigate through my application and the toolbar is present on all pages. Each time a new page is displayed I am closing the current frame and opening a new one, using the following code:
java.awt.Window win[] = java.awt.Window.getWindows();
for(int i=0;i<win.length;i++){
win[i].dispose();
}
I am doing it this way as the ActionListeners are declared in the toolbar class, whilst the frames for each page are declared at runtime and are not static.
This all works fine except for one particular case-the "cancel" button, where the first time the frame is accessed it will close once. The second time it will close and re open 2 times, the third 3 and so on. I have tracked this using the "counter" in the code.
I have minimised the code to recreate the same behaviour, as below:
Toolbar Class
public class Toolbar {
static JButton buttonCancel = new JButton("Cancel");
static int counter;
public static JPanel Toolbar(String panelname){
FlowLayout layout = new FlowLayout();
JPanel Toolbar = new JPanel(new BorderLayout());
Toolbar.setLayout(layout);
GridLayout GLayout = new GridLayout(2,1);
GLayout.setVgap(0);
JPanel container2 = new JPanel();
if(panelname.matches("Customers")){
container2.setLayout(GLayout);
JButton buttonAddCust = new JButton("Add Cust");
container2.add(buttonAddCust, BorderLayout.PAGE_START);
buttonAddCust.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
java.awt.Window win[] = java.awt.Window.getWindows();
for(int i=0;i<win.length;i++){
win[i].dispose();
}
Customers.AddCustomersGui();
}
});
}
JPanel container21 = new JPanel();
if(panelname.matches("Add Customers")){
container21.setLayout(GLayout);
container21.add(buttonCancel, BorderLayout.PAGE_START);
buttonCancel.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
counter ++;
java.awt.Window win[] = java.awt.Window.getWindows();
for(int i=0;i<win.length;i++){
win[i].dispose();
}
System.out.println("Coutner " + counter);
Customers.CustomersGui();
}
});
}
Toolbar.add(container2);
Toolbar.add(container21);
return Toolbar;
}
}
GUI class
public class Customers extends Toolbar{
public static void CustomersGui(){
final JFrame frame = new JFrame("Customers");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel customers = new JPanel();
customers.add(Toolbar.Toolbar(frame.getTitle()));
frame.setContentPane(customers);
frame.setSize(1200,500);
frame.setVisible(true);
}
public static void AddCustomersGui(){
final JFrame frame1 = new JFrame("Add Customers");
frame1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel Addcustomers = new JPanel();
Addcustomers.add(Toolbar.Toolbar(frame1.getTitle()));
frame1.setContentPane(Addcustomers);
frame1.setSize(1200,500);
frame1.setVisible(true);
}
}
main class
public static void main(String[] args) {
Customers.CustomersGui();
}
You are adding a new ActionListener to the buttonCancel, with each iteration of your code and this is the reason for your program's behavior.
Also, as per my comment, you state,
Each time a new page is displayed I am closing the current frame and opening a new one.
A better design is probably not to swap windows which can be annoying, but rather to swap JPanel views using a CardLayout. Please read The Use of Multiple JFrames, Good/Bad Practice?.
For example, add this line of code to your program:
if (panelname.matches("Add Customers")) {
container21.setLayout(GLayout);
container21.add(buttonCancel, BorderLayout.PAGE_START);
buttonCancel.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
counter++;
java.awt.Window win[] = java.awt.Window.getWindows();
for (int i = 0; i < win.length; i++) {
win[i].dispose();
}
System.out.println("Coutner " + counter);
Customers.CustomersGui();
}
});
// ***** add this here **********
System.out.println("buttonCancel ActionListener count: "
+ buttonCancel.getListeners(ActionListener.class).length);
}
and you'll see that the ActionListeners get added multiple times to this button.
An example of swapping views:
import java.awt.*;
import java.awt.event.ActionEvent;
import javax.swing.*;
#SuppressWarnings("serial")
public class SwapPanels extends JPanel {
public static final String CUSTOMER = "customer";
public static final String ADD_CUSTOMER = "Add Customer";
protected static final int PREF_W = 800;
protected static final int PREF_H = 600;
public static final String CANCEL = "Cancel";
private CardLayout cardLayout = new CardLayout();
public SwapPanels() {
setLayout(cardLayout);
add(createCustomerPanel(CUSTOMER), CUSTOMER);
add(createAddCustomerPanel(ADD_CUSTOMER), ADD_CUSTOMER);
}
public void showCard(String key) {
cardLayout.show(this, key);
}
public JPanel createAddCustomerPanel(String name) {
JPanel addCustPanel = new JPanel() {
#Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(PREF_W, PREF_H);
}
};
addCustPanel.setName(name);
addCustPanel.setBorder(BorderFactory.createTitledBorder(name));
addCustPanel.add(new JButton(new AbstractAction(CANCEL) {
{
int mnemonic = (int)getValue(NAME).toString().charAt(0);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
if (CANCEL.equals(e.getActionCommand())) {
SwapPanels.this.showCard(CUSTOMER);
}
}
}));
return addCustPanel;
}
private JPanel createCustomerPanel(String name) {
JPanel custPanel = new JPanel() {
#Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(PREF_W, PREF_H);
}
};
custPanel.setName(name);
custPanel.setBorder(BorderFactory.createTitledBorder(name));
custPanel.add(new JButton(new AbstractAction(ADD_CUSTOMER) {
{
int mnemonic = (int)getValue(NAME).toString().charAt(0);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
if (ADD_CUSTOMER.equals(e.getActionCommand())) {
SwapPanels.this.showCard(ADD_CUSTOMER);
}
}
}));
return custPanel;
}
private static void createAndShowGui() {
JFrame frame = new JFrame("SwapPanels");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new SwapPanels());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
I'd like to create a new window which is used in POS system. The user input is for an amount of money the customer has and the window has to display the exchange amount. I'm new with JOptionPane feature (I have been using JAVAFX and it's different).
This is my code:
public static void main(String[] argv) throws Exception {
String newline = System.getProperty("line.separator");
int cost = 100;
int amount = Integer.parseInt(JOptionPane.getText()) // this is wrong! This needs to come from user input box in the same window.
JFrame frame = new JFrame();
String message = "Enter the amount of money"+newline+"The exchange money is: "+amount-cost;
String text = JOptionPane.showInputDialog(frame, message);
if (text == null) {
// User clicked cancel
}
Is there any suggestion?
use InputDialog for get userinput
public static void main(String[] argv) throws Exception {
//JFrame frame = new JFrame();
//frame.setVisible(true);
int cost = 100;
JLabel l=new JLabel("The exchange money is");
JPanel p=new JPanel(new GridLayout(1, 2, 10, 10));
p.setPreferredSize(new Dimension(400, 50));
JTextField t=new JTextField("Enter the amount of money");
t.addKeyListener(new java.awt.event.KeyAdapter() {
public void keyReleased(java.awt.event.KeyEvent evt) {
try{
int amount=Integer.parseInt(t.getText());
l.setText("The exchange money is: \n" + (amount - cost));
}catch(Exception ex){
// ex.printStackTrace();
}
}
});
p.add(t);
p.add(l);
int option = JOptionPane.showConfirmDialog(null,p,"JOptionPane Example : ",JOptionPane.OK_CANCEL_OPTION,JOptionPane.PLAIN_MESSAGE);
if(option==0){
System.out.println("ok clicked");
}else{
System.out.println("cancel clicked");
}
}
What you need to do, is to create your own custom JOptionPane, that has it's own components, instead of using the build in one's.
Place a JTextField in it, and add a DocumentListener to that, so that when you change something on it, it can be reciprocated on to the status label, as need be.
Try this small example:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class JOptionPaneExample {
private JLabel label;
private JTextField tfield;
private JLabel statusLabel;
private static final int GAP = 5;
private void displayGUI() {
JOptionPane.showMessageDialog(null, getPanel());
}
private JPanel getPanel() {
JPanel panel = new JPanel(new GridLayout(0, 1));
label = new JLabel("Enter something: ", JLabel.CENTER);
tfield = new JTextField(10);
tfield.getDocument().addDocumentListener(new MyDocumentListener());
JPanel controlPanel = new JPanel();
controlPanel.add(label);
controlPanel.add(tfield);
panel.add(controlPanel);
statusLabel = new JLabel("", JLabel.CENTER);
panel.add(statusLabel);
return panel;
}
private class MyDocumentListener implements DocumentListener {
#Override
public void changedUpdate(DocumentEvent de) {
updateStatus();
}
#Override
public void insertUpdate(DocumentEvent de) {
updateStatus();
}
#Override
public void removeUpdate(DocumentEvent de) {
updateStatus();
}
private void updateStatus() {
statusLabel.setText(tfield.getText());
}
}
public static void main(String[] args) {
Runnable runnable = new Runnable() {
#Override
public void run() {
new JOptionPaneExample().displayGUI();
}
};
EventQueue.invokeLater(runnable);
}
}
Try using this:
if( myJOptionPane.getValue() instanceOf String){
String myString = (String) myJOptionPane.getValue();
}
Then use the result of myString to do whatever you intend to do.
I'm trying to create a java GUI that outputs a value once the value is selected from a drop down and the apply button is pressed. The problem is this is my first time creating a GUI in java, I just used some sample code I found and reworked it, but I'm unsure how to output the value I want. The code is below and the value I want to output is "colour".
package state;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class GUI extends JFrame {
Font font = new Font("Cambria", Font.PLAIN, 20);
static final String Colour[] = {"Blue", "Yellow"};
static final String Pitch[] = {"Main Pitch", "Side Pitch"};
final static int maxGap = 20;
JComboBox colourComboBox;
JComboBox pitchComboBox;
Label colourLabel;
Label pitchLabel;
JButton applyButton = new JButton("Apply settings");
GridLayout experimentLayout = new GridLayout(0,2);
public GUI(String name) {
super(name);
setResizable(false);
}
public void initGaps() {
colourComboBox = new JComboBox(Colour);
colourComboBox.setFont(font);
pitchComboBox = new JComboBox(Pitch);
pitchComboBox.setFont(font);
}
public void addComponentsToPane(final Container pane) {
initGaps();
final JPanel compsToExperiment = new JPanel();
compsToExperiment.setLayout(experimentLayout);
JPanel controls = new JPanel();
controls.setLayout(new GridLayout(0,2));
//Set up components preferred size
JButton b = new JButton("Just fake button");
Dimension buttonSize = b.getPreferredSize();
compsToExperiment.setPreferredSize(new Dimension((int)(buttonSize.getWidth() * 3.3)+maxGap,
(int)(buttonSize.getHeight() * 1.5)+maxGap * 5));
//Add buttons to experiment with Grid Layout
colourLabel = new Label("Select Robot Colour:");
colourLabel.setFont(font);
pitchLabel = new Label("Select Pitch:");
pitchLabel.setFont(font);
compsToExperiment.add(colourLabel);
compsToExperiment.add(colourComboBox);
compsToExperiment.add(pitchLabel);
compsToExperiment.add(pitchComboBox);
controls.add(applyButton);
//Process the Apply gaps button press
applyButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
String colour = (String)colourComboBox.getSelectedItem();
String pitch = (String)pitchComboBox.getSelectedItem();
}
});
pane.add(compsToExperiment, BorderLayout.NORTH);
pane.add(new JSeparator(), BorderLayout.CENTER);
pane.add(controls, BorderLayout.SOUTH);
}
/**
* Create the GUI and show it. For thread safety,
* this method is invoked from the
* event dispatch thread.
*/
private static void createAndShowGUI() {
//Create and set up the window.
GUI frame = new GUI("Match Conditions");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Set up the content pane.
frame.addComponentsToPane(frame.getContentPane());
//Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
/* Use an appropriate Look and Feel */
try {
//UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel");
} catch (UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
} catch (IllegalAccessException ex) {
ex.printStackTrace();
} catch (InstantiationException ex) {
ex.printStackTrace();
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
}
/* Turn off metal's use of bold fonts */
UIManager.put("swing.boldMetal", Boolean.FALSE);
//Schedule a job for the event dispatch thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
You can get the text using the getSelectedItem() function in JComboBox.
ex.
pitchComboBox.getSelectedItem().toString()
colourComboBox.getSelectedItem().toString()
Show Output as in ??
You can use this...
JOptionPane.showMessageDialog(null, "Colour"+colour); to show it in a dialog.
For architecture and design purposes I would like to design my GUI with a class for each card in a Java Swing CardLayout. and then have a mainapp that builds the GUI. I am having trouble doing this right now.
I would like to example have a class for the main menu with all the button locations etc. and then just instantiate that card and add it to the layout in another class. Does anyone know how to achieve this?
Perhaps you want to give your class that uses the CardLayout a public loadCard method, something like
public void loadCard(JComponent component, String key) {
cardHolderPanel.add(component, key);
}
where cardHolderPanel is the container that holds the cards.
Since your creating classes to act as cards, consider having them all extend from a base abstract class or an interface that has a method that allows this class to hold its own key String. Either that or simply use the JComponent name property to have a component hold its own key String, one that can easily be obtained via getName().
For a more detailed answer, you may need to give us more details on your current application and its structure.
very simple example that held Swing Objects generated from different Java Classes
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class OnTheFlyImageTest extends JFrame {
private static final long serialVersionUID = 1L;
private JPanel cardPanel;
private CardLayout cardLayout;
public OnTheFlyImageTest() {
JPanel cp = new JPanel(new BorderLayout());
cp.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
cardLayout = new CardLayout(5, 5);
cardPanel = new JPanel(cardLayout);
cp.add(cardPanel);
for (int i = 0; i < 100; i++) {// Create random panels for testing.
String name = "ImagePanel" + (i + 1);
String image = (i & 1) == 0 ? "foo.gif" : "bar.gif";
ImagePanel imgPanel = new ImagePanel(name, image);
cardPanel.add(imgPanel, name);
cardLayout.addLayoutComponent(imgPanel, name);
}
JPanel buttonPanel = new JPanel(new GridLayout(1, 2, 5, 5));
JButton prevButton = new JButton("< Previous");
prevButton.setActionCommand("Previous");
prevButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
cardLayout.previous(cardPanel);
}
});
buttonPanel.add(prevButton);
JButton nextButton = new JButton("Next >");
nextButton.setActionCommand("Next");
nextButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
cardLayout.next(cardPanel);
}
});
buttonPanel.add(nextButton);
JPanel temp = new JPanel(new BorderLayout());
temp.add(buttonPanel, BorderLayout.LINE_END);
cp.add(temp, BorderLayout.SOUTH);
setContentPane(cp);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setTitle("Test");
pack();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new OnTheFlyImageTest().setVisible(true);
}
});
}
}
class ImagePanel extends JPanel {
private static final long serialVersionUID = 1L;
private String imgString;
private JLabel imgLabel;
public ImagePanel(String name, String imgString) {
setName(name);
this.imgString = imgString;
setLayout(new BorderLayout());
// Ensure size is correct even before any image is loaded.
setPreferredSize(new Dimension(640, 480));
}
#Override
public void setVisible(boolean visible) {
if (visible) {
System.err.println(getName() + ": Loading and adding image");
ImageIcon icon = new ImageIcon(imgString);
imgLabel = new JLabel(icon);
add(imgLabel);
}
super.setVisible(visible);
if (!visible) { // Do after super.setVisible() so image doesn't "disappear".
System.err.println(getName() + ": Removing image");
if (imgLabel != null) { // Before display, this will be null
remove(imgLabel);
imgLabel = null; // Hint to GC that component/image can be collected.
}
}
}
}
I have a JFrame which contains 3 JPanels. I want to pass the JTextField value of one panel to other. Each panel is shown using JTabbedPane. I am getting null when i access the value of other text field. How can i access?
You don't show any code, and so it's impossible to know why you're getting "null" values. Two possible solutions if you want all three JPanels to hold JTextFields with the same content:
Put the shared JTextField outside of the JPanels held by the JTabbedPane and instead in a JPanel that holds the JTabbedPane, so that the field is always visible no matter what tab is displayed, or
Use several JTextFields but have them share the same Document or "model".
e.g.,
import java.awt.Dimension;
import javax.swing.*;
import javax.swing.text.PlainDocument;
public class SharedField extends JTabbedPane {
private static final int TAB_COUNT = 5;
private static final int MY_WIDTH = 600;
private static final int MY_HEIGHT = 300;
PlainDocument doc = new PlainDocument();
public SharedField() {
for (int i = 0; i < TAB_COUNT; i++) {
JTextField tField = new JTextField(10);
tField.setDocument(doc);
JPanel panel = new JPanel();
panel.add(tField);
add("Panel " + i, panel);
// to demonstrate some of the JTextFields acting like
// a label
if (i % 2 == 1) { // if i is odd
tField.setEditable(false);
tField.setBorder(null);
}
}
}
#Override
public Dimension getPreferredSize() {
return new Dimension(MY_WIDTH, MY_HEIGHT);
}
private static void createAndShowUI() {
JFrame frame = new JFrame("SharedField");
frame.getContentPane().add(new SharedField());
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();
}
});
}
}
Edit 1
I see that you've cross-posted this on java-forums.org/ where you show some of your code:
pacage Demotool;
Class:MainFrame
This is the actionPerformed code of first panel
both str and scrTxt is (public static)
public void actionPerformed(ActionEvent e)
{
String act=e.getActionCommand();
if(act.equals("ADD"))
{
str=scrnTxt.getText();
System.out.println("Hi :"+str);
Demotool.DemoTool.jtp.setSelectedIndex(1);
}
}
using the belove code i tried to access the data but I am getting null String:
System.out.println("Hello:"+Demotool.MainFrame.str);
Problems:
Don't use static variables or methods unless you have a good reason to do so. Here you don't.
You're may be trying to access the MainFrame.str variable before anything has been put into it, making it null, or you are creating a new MainFrame object in your second class, one that isn't displayed, and thus one whose str variable is empty or null -- hard to say.
Either way, this design is not good. You're better off showing us a small demo program that shows your problem with code that compiles and runs, an sscce, so we can play with and modify your code and better be able to show you a decent solution.
One such decent solution is to add a DocumentListener to the JTextField so that changes to the text held by the JTextField are "pushed" into the observers that are listening for changes (your other classes).
For example, using DocumentListeners:
import java.awt.Dimension;
import javax.swing.*;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
import javax.swing.text.BadLocationException;
public class SharedField2 extends JTabbedPane {
private static final int LABEL_PANEL_COUNT = 4;
private static final int MY_WIDTH = 600;
private static final int MY_HEIGHT = 300;
public SharedField2() {
TextFieldPanel tfPanel = new TextFieldPanel();
LabelPanel[] labelPanels = new LabelPanel[LABEL_PANEL_COUNT];
add("TextFieldPanel", tfPanel);
for (int i = 0; i < labelPanels.length; i++) {
labelPanels[i] = new LabelPanel();
// add each label panel's listener to the text field
tfPanel.addDocumentListenerToField(labelPanels[i].getDocumentListener());
add("Label Panel " + i, labelPanels[i]);
}
}
#Override
public Dimension getPreferredSize() {
return new Dimension(MY_WIDTH, MY_HEIGHT);
}
private static void createAndShowUI() {
JFrame frame = new JFrame("SharedField2");
frame.getContentPane().add(new SharedField2());
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();
}
});
}
}
class TextFieldPanel extends JPanel {
private JTextField tField = new JTextField(10);
public TextFieldPanel() {
add(tField);
}
public void addDocumentListenerToField(DocumentListener listener) {
tField.getDocument().addDocumentListener(listener);
}
}
class LabelPanel extends JPanel {
private DocumentListener myListener;
private JLabel label = new JLabel();
public LabelPanel() {
add(label);
myListener = new DocumentListener() {
#Override
public void changedUpdate(DocumentEvent e) {
updateLabel(e);
}
#Override
public void insertUpdate(DocumentEvent e) {
updateLabel(e);
}
#Override
public void removeUpdate(DocumentEvent e) {
updateLabel(e);
}
private void updateLabel(DocumentEvent e) {
try {
label.setText(e.getDocument().getText(0,
e.getDocument().getLength()));
} catch (BadLocationException e1) {
e1.printStackTrace();
}
}
};
}
public DocumentListener getDocumentListener() {
return myListener;
}
}
One simple solution will be making JTextField global so all panel can access it.
Make sure all your panel can access JTextField that is textField is globally accessible.
Following code demonstrate this:
JTextField textField = new JTextField(25);
JLabel labelForPanel2 = new JLabel(),labelForPanel3 = new JLabel();
private void panelDemo() {
JFrame frame = new JFrame();
frame.setSize(400, 400);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel1 = new JPanel();
JPanel panel2 = new JPanel();
JPanel panel3 = new JPanel();
JTabbedPane tabbedPane = new JTabbedPane();
tabbedPane.addTab("Tab 1", panel1);
tabbedPane.addTab("Tab 2", panel2);
tabbedPane.addTab("Tab 3", panel3);
panel1.add(textField);
panel2.add(labelForPanel2);
panel3.add(labelForPanel3);
textField.addKeyListener(new KeyAdapter() {
#Override
public void keyReleased(KeyEvent e) {
labelForPanel2.setText(textField.getText());
labelForPanel3.setText(textField.getText());
}
});
frame.add(tabbedPane);
frame.setVisible(true);
}
I don't know what exactly are you going to achieve, but maybe try data binding?
Take a look at BetterBeansBinding library.