as I said in other posts I'm new in Java and I'm having some dumb problems, here's the deal:
I have a radioButton (radioStock) and a textField (stockField). I want stockField to be setEnabled(false) by default, no problem with that, and whenever the radioStock is checked, set the stockField enabled on true. I wrote this code, but it doesn't work.
if (radioStock.isSelected()) {
stockField.setEnabled(true);
}else{
stockField.setEnabled(false);
}
That code needs to be in a listener that is attached to the JRadioButton such as an ActionListener or ItemListener. And you don't even need the if blocks since all you'd need is one line of code inside of the listener:
radioStock.addItemListener(new ItemListener() {
#Override
public void itemStateChanged(ItemEvent itemEvent) {
stockField.setEnabled(itemEvent.getStateChange() == ItemEvent.SELECTED);
}
});
For more on use of JRadioButtons, please check out the tutorial: button tutorial.
Edit my SSCCE
import java.awt.event.*;
import javax.swing.*;
public class ItemListenereg {
private static void createAndShowGui() {
final JRadioButton radioStock = new JRadioButton("Stock", true);
final JTextField stockField = new JTextField(10);
JPanel panel = new JPanel();
panel.add(radioStock);
panel.add(stockField);
radioStock.addItemListener(new ItemListener() {
#Override
public void itemStateChanged(ItemEvent itemEvent) {
stockField.setEnabled(itemEvent.getStateChange() == ItemEvent.SELECTED);
}
});
JOptionPane.showMessageDialog(null, panel);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
This should work
radioStock.addActionListener(new ActionListener()
{
#Override
public void actionPerformed(ActionEvent e)
{
if(radioStock == e.getSource())
{
stockField.setEnabled(radioStock.isSelected());
}
}
});
Related
I have some problems with using dispose() method in my GUI project.
I' am making a GUI swing application for some kind of Elections in IntelliJ.
My problem is, by clicking a button(Confirm1, or 2 or 3) I want to open new JFrame which is checking the age of voter and closes the current JFrame where this button is located by calling dispose().
But frame.dispose(); doesn't work.
I have my JFrame declared in public static main().
Should I make reference for it in my ActionListener? I have been looking for solution, but I couldn't find any.
Here is a code:
import javax.swing.*; //another libraries
public class ElectionGUI {
private JPanel labelElection; // another texfields or etc.
private JButton Confirm1;
private JButton Confirm3;
private JButton Confirm2;
private JPanel Elections;
public VotesGUI(){
Votes votes = new Votes("...","...",0);
listX.addListSelectionListener(new ListSelectionListener() {
#Override
public void valueChanged(ListSelectionEvent e) {
if(!e.getValueIsAdjusting()){
NrX.setText(listX.getSelectedValue().toString());
}
}
});
listY.addListSelectionListener(new ListSelectionListener() {
#Override
public void valueChanged(ListSelectionEvent e) {
if(!e.getValueIsAdjusting()){
NrY.setText(listY.getSelectedValue().toString());
}
}
});
listZ.addListSelectionListener(new ListSelectionListener() {
#Override
public void valueChanged(ListSelectionEvent e) {
if(!e.getValueIsAdjusting()){
NrZ.setText(listZ.getSelectedValue().toString());
}
}
});
Confirm1.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
votes.VotesX();
votes.countVotes();
CheckAge age = new CheckAge();
age.Check(); /// referention, to my next //Jframe called psvm Check();
}
});
Confirm2.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
votes.VotesY();
votes.countVotes();
CheckAge age = new CheckAge();
age.Check();
}
});
Confirm3.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
votes.VotesZ();
votes.countVotes();
CheckAge age = new CheckAge();
age.Check();
}
});
}
public static void main(String[] args) {
JFrame frame = new JFrame("Elentions");
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.setVisible(true);
frame.setContentPane(new ElectionGUI().labelElection);
frame.pack();
}
}
I want to initialize a Graphical User Interface (GUI) for the user to input a form. After this is accomplished i want to open a new GUI, but as soon as the first GUI pops-up the next one is initialized to.
Is there any way to solve this without using waits and notifies?
here is an example of my code:
public static void main(String[] args) {
new GUIForm();
// wait until the user inputs the complete form
new GUIWelcome();
}
It is really simple I woild like to keep it that way.
Create an Interface OnActionListener
public interface OnActionListener {
public void onAction();
}
Add these code in GUIForm class
private OnActionListener listener;
private JButton action;
public GUIForm(OnActionListener listener) {
this.listener = listener;
action = new JButton("Action");
action.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
GUIForm.this.listener.onAction();
}
});
}
Now you can achieve that
new GUIForm(new OnActionListener() {
#Override
public void onAction() {
new GUIWelcome();
}
});
You need to use some sort pub/sub mechanism. This in a nutshell is what you need:
public class PubSub {
public static void main(String[] args) {
JFrame frame1 = new JFrame("GUIForm");
frame1.setSize(640, 480);
JButton button = new JButton("User Input");
JFrame frame2 = new JFrame("Welcome");
frame2.setSize(320, 240);
button.addMouseListener(new MouseAdapter() {
#Override
public void mouseEntered(MouseEvent e) {
button.setCursor(new Cursor(Cursor.HAND_CURSOR));
}
#Override
public void mouseExited(MouseEvent e) {
button.setCursor(new Cursor(Cursor.DEFAULT_CURSOR));
}
#Override
public void mouseClicked(MouseEvent e) {
frame2.setVisible(true);
}
});
frame1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame1.add(button);
frame1.setVisible(true);
}
}
This version uses JFrame's listeners, but you could implement your on callback mechanism to accomplish the same
I have a login form where a user can enter his credentials to login. I have a JLabel that serves to display the text telling the user that the user name cannot be empty. This label is display after a user click the login button when the text field is empty.
I want that the moment the user starts typing in the text field the label with the information should disappear.How do I achieve this behavior?
Here is the code:
public class JTextFiledDemo {
private JFrame frame;
JTextFiledDemo() {
frame = new JFrame();
frame.setVisible(true);
frame.setSize(300, 300);
frame.setLayout(new GridLayout(4, 1));
frame.setLocationRelativeTo(null);
iniGui();
}
private void iniGui() {
JLabel error = new JLabel(
"<html><font color='red'> Username cannot be empty!<></html>");
error.setVisible(false);
JButton login = new JButton("login");
JTextField userName = new JTextField(10);
frame.add(userName);
frame.add(error);
frame.add(login);
frame.pack();
login.addActionListener((ActionEvent) -> {
if (userName.getText().equals("")) {
error.setVisible(true);
}
});
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
JTextFiledDemo tf = new JTextFiledDemo();
}
});
}
}
You have to create DocumentListener:
DocumentListener dl = new DocumentListener()
{
#Override
public void insertUpdate(DocumentEvent de)
{
error.setVisible(false);
}
#Override
public void removeUpdate(DocumentEvent de)
{
//
}
#Override
public void changedUpdate(DocumentEvent de)
{
error.setVisible(false);
}
};
then for your text fields:
login.getDocument().addDocumentListener(dl);
For that purposes you need to use DocumentListener on your JTextField, here is tutorial.
As example:
userName.getDocument().addDocumentListener(new DocumentListener() {
#Override
public void insertUpdate(DocumentEvent de){
event(de);
}
#Override
public void removeUpdate(DocumentEvent de) {
event(de);
}
#Override
public void changedUpdate(DocumentEvent de){
event(de);
}
private void event(DocumentEvent de){
error.setVisible(de.getDocument().getLength() == 0);
// as mentioned by nIcE cOw better to use Document from parameter
frame.revalidate();
frame.repaint();
}
});
error must be final(for java lower than 8 version).
Also at start your field is empty, so may be need to use setVisible(true) on error label.
You can add a keyListener in the input filed
userName.addKeyListener(new KeyListener() {
#Override
public void keyTyped(KeyEvent arg0) {
}
#Override
public void keyReleased(KeyEvent arg0) {
}
#Override
public void keyPressed(KeyEvent arg0) {
error.setVisible(false);
}
});
I want to update my text area along with typing in the text field but i get a delay of 1 keystroke while typing i.e when i press a key the previous key is displayed.Here is my snippet
private void jTextField1KeyTyped(java.awt.event.KeyEvent evt)
{
String a = jTextField1.getText();
jTextArea1.setText(a);
}
I would not recommend using KeyListeners
Simply add a DocumentListener to your JTextField via:
textField.getDocument().addDocumentListener(new DocumentListener() {
#Override
public void insertUpdate(DocumentEvent de) {
}
#Override
public void removeUpdate(DocumentEvent de) {
}
#Override
public void changedUpdate(DocumentEvent de) {
}
});
Inside each of the methods ( insertUpdate,removeUpdate and changedUpdate) simply put in a call to set the text of your JTextArea via setText():
textArea.setText(textField.getText());
Here is an example I made:
import java.awt.BorderLayout;
import javax.swing.*;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
public class Test {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Test().createAndShowUI();
}
});
}
private void createAndShowUI() {
final JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
initComponents(frame);
frame.setResizable(false);
frame.pack();
frame.setVisible(true);
}
private void initComponents(JFrame frame) {
final JTextField jtf = new JTextField(20);
final JTextArea ta = new JTextArea(20,20);
ta.setEditable(false);
jtf.getDocument().addDocumentListener(new DocumentListener() {
#Override
public void insertUpdate(DocumentEvent de) {
ta.setText(jtf.getText());
}
#Override
public void removeUpdate(DocumentEvent de) {
ta.setText(jtf.getText());
}
#Override
public void changedUpdate(DocumentEvent de) {
//Plain text components don't fire these events.
}
});
frame.getContentPane().add(jtf, BorderLayout.WEST);
frame.getContentPane().add(ta, BorderLayout.EAST);
}
}
You should do that under the keyReleased event instead of the keyTyped and it will work as you need.
You need to wait till the event on your TextField is processed before updating the TextArea. Your code update the TextArea before the TextField is done processing the new typed character. Hence the text set in the TextArea is one keystroke behind.
You could try using recursion by referencing the method inside the method (avoid loops though).
I'm trying to build a simple Java Swing application using the MVC architecture pattern. What I've done is create the user interface components (as private) in my views, and have public methods that return the components. These methods are then called by the controllers, through which I can write methods for event/action listeners. Below is a sample example:
View:
private JButton btnAdd;
public JButton getBtnAdd(){
return btnAdd;
}
Control:
myGuiFrame gui = new myGuiFrame();
//on add button clicked
gui.getBtnAdd().addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
//calls to model
}
});
Is this implementation correct?
If so, then I'm having a problem with FocusListeners. When I create a FocusListener in my view, the focusLost and focusGained methods are created within the view.
private FocusListener l;
someComponent.addFocusListener(l);
l = new FocusListener() {
#Override
public void focusLost(FocusEvent e) {
// TODO Auto-generated method stub
}
#Override
public void focusGained(FocusEvent e) {
// TODO Auto-generated method stub
}
};
I want all the event handlers to be in my controllers. My question is ... is there a way I can call/declare the focusLost and focusGained methods from my controller? I tried to define the FocusListener as public so that I can define it in my controller:
view:
public FocusListener l;
public someComponentType someComponent;
controller:
gui.l = new FocusListener() {
#Override
public void focusLost(FocusEvent e) {
// TODO Auto-generated method stub
}
#Override
public void focusGained(FocusEvent e) {
// TODO Auto-generated method stub
gui.someComponent.addFocusListener(gui.l);
}
};
This however does not work.
Is it possible to handle FocusEvents from the controller?
EDIT:
Gosh, my bad. Didn't quite understand what Robin was all about. I was too fixated on having the FocusListener explicitly defined somewhere. A simple:
gui.getTextFieldEmployeeCode().addFocusListener(new FocusListener() {
#Override
public void focusLost(FocusEvent e) {
// TODO Auto-generated method stub
}
#Override
public void focusGained(FocusEvent e) {
// TODO Auto-generated method stub
System.out.println("YES!!!");
}
});
in the controller would work just fine in the manner I planned to do it, though I quite like how nIcE cOw's gone about it. Just out of curiosity, is there a standard or widely accepted manner of implementing MVC on Swing Apps?
As far as I understood, the way you doing is this. Better still, I prefer the Anonymous Classes, they respect the concept of Encapsulation. Here try your hands on this code, see what you can grasp with this :
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class View
{
private JButton focusButton;
private JButton spareButton;
private void createAndDisplayGUI()
{
JFrame frame = new JFrame("VIEW");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
JPanel contentPane = new JPanel();
contentPane.setLayout(new FlowLayout(FlowLayout.LEFT, 5, 5));
focusButton = new JButton("GAINED/LOST");
focusButton.addFocusListener(new ButtonController(this));
spareButton = new JButton("SPARE");
spareButton.setOpaque(true);
spareButton.addActionListener(new ButtonController(this));
spareButton.addFocusListener(new ButtonController(this));
contentPane.add(focusButton);
contentPane.add(spareButton);
frame.setContentPane(contentPane);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public JButton getFocusButton()
{
return focusButton;
}
public JButton getSpareButton()
{
return spareButton;
}
public static void main(String... args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
new View().createAndDisplayGUI();
}
});
}
}
class ButtonController implements FocusListener, ActionListener
{
private View view;
private JButton focusButton;
private JButton spareButton;
public ButtonController(View v)
{
view = v;
focusButton = view.getFocusButton();
spareButton = view.getSpareButton();
}
public void actionPerformed(ActionEvent ae)
{
JButton button = (JButton) ae.getSource();
if (button == spareButton)
{
spareButton.setBackground(Color.BLUE);
focusButton.setEnabled(true);
}
}
public void focusGained(FocusEvent fe)
{
JButton button = (JButton) fe.getSource();
if (button == focusButton)
{
focusButton.setEnabled(true);
}
else if (button == spareButton)
{
spareButton.setBackground(Color.WHITE);
}
}
public void focusLost(FocusEvent fe)
{
JButton button = (JButton) fe.getSource();
if (button == focusButton)
{
focusButton.setEnabled(false);
}
else if (button == spareButton)
{
spareButton.setBackground(Color.DARK_GRAY.darker());
}
}
}
Another approach, if you feel irritated by getters/setters and sending references around, is to define one inner class as follows (A Simple workaround for the previous example) :
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class View
{
private JButton focusButton;
private JButton spareButton;
private void createAndDisplayGUI()
{
JFrame frame = new JFrame("VIEW");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
JPanel contentPane = new JPanel();
contentPane.setLayout(new FlowLayout(FlowLayout.LEFT, 5, 5));
focusButton = new JButton("GAINED/LOST");
focusButton.addFocusListener(new ButtonController());
spareButton = new JButton("SPARE");
spareButton.setOpaque(true);
spareButton.addActionListener(new ButtonController());
spareButton.addFocusListener(new ButtonController());
contentPane.add(focusButton);
contentPane.add(spareButton);
frame.setContentPane(contentPane);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
private class ButtonController implements FocusListener, ActionListener
{
public void actionPerformed(ActionEvent ae)
{
JButton button = (JButton) ae.getSource();
if (button == spareButton)
{
spareButton.setBackground(Color.BLUE);
focusButton.setEnabled(true);
}
}
public void focusGained(FocusEvent fe)
{
JButton button = (JButton) fe.getSource();
if (button == focusButton)
focusButton.setEnabled(true);
else if (button == spareButton)
spareButton.setBackground(Color.WHITE);
}
public void focusLost(FocusEvent fe)
{
JButton button = (JButton) fe.getSource();
if (button == focusButton)
focusButton.setEnabled(false);
else if (button == spareButton)
spareButton.setBackground(Color.DARK_GRAY.darker());
}
}
public static void main(String... args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
new View().createAndDisplayGUI();
}
});
}
}