Develop Reference

how to send string from ChildFrame to ParentFrame and repaint ParentFrame?

ParentFrame shows ArrayList and one "ADD" Button. Once I click "ADD" Button on ParentFrame, then ChildFrame shows up.
On ChildFrame, I type in a String and click "OK" Button then it should transfer its String to ParentFrame. Finally ParentFrame should be repainted with newly added String.
I'm having trouble with repainting but also I might failed to send String from Child to Parent since Parent didn't get repainted.
I tried several things in two or three other points of view but following code seems like to work but......
I need your help!!
ParentFrame
import javax.swing.*;
import java.awt.event.*;
import java.util.*;
import java.awt.*;
#SuppressWarnings("serial")
public class parentFrame extends JFrame {
ArrayList<String> list = new ArrayList<>(){{add("test1"); add("test2");}};
JButton add;
JPanel big, small;
JLabel content;
childFrame addFrame;
public parentFrame() {
super("parent frame");
super.setLayout(new BorderLayout());
super.setSize(600,600);
big = new JPanel();
for(int i=0; i<list.size(); i++) {
content = new JLabel();
content.setText(list.get(i));
big.add(content);
}
super.add(big, BorderLayout.CENTER);
add = new JButton("ADD");
add.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
addFrame = new childFrame();
/* By next 3 lines, I'm trying to transfer the value of childFrame's test to this parentFrame's list. */
list.add(addFrame.getTestString());
big.revalidate();
big.repaint();
}
});
super.add(add, BorderLayout.SOUTH);
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public static void main(String[] args) {
new parentFrame();
}
}
2.ChildFrame
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
#SuppressWarnings("serial")
public class childFrame extends JFrame {
String test;
JTextField name;
JButton ok, cancel;
public childFrame() {
super("child frame");
super.setLayout(new BorderLayout());
super.setSize(400,200);
JPanel centerPanel = new JPanel(new GridLayout(1,1));
centerPanel.setSize(150, 100);
name = new JTextField();
centerPanel.add(name);
JPanel bottomPanel = new JPanel(new FlowLayout());
ok = new JButton("OK");
ok.addActionListener(new OKListener());
super.add(ok);
cancel = new JButton("CANCEL");
cancel.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
dispose();
}
});
bottomPanel.add(cancel);
bottomPanel.add(ok);
super.add(centerPanel, BorderLayout.CENTER);
super.add(bottomPanel, BorderLayout.SOUTH);
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
class OKListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
test = name.getText();
dispose();
}
}
public String getTestString() {
return test;
}
}

Your problem is here:
public void actionPerformed(ActionEvent e) {
addFrame = new childFrame();
list.add(addFrame.getTestString());
big.revalidate();
big.repaint();
}
Since your child frame is not a modal window (for example, a JOptionPane is a modal dialog window), it does not halt program flow in the calling window. You call .getTestString() immediately on creation of the child frame but before the user has had any chance to enter in any data (again, because program flow in the calling window is not halted).
The solution is to make your child "frame" in fact a modal JDialog. This will pretty much solve the whole issue. So, don't have the child frame extend from JFrame, but rather extend JDialog, and use the JDialog constructor that makes it modal (see the JDialog API).
e.g.,
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
#SuppressWarnings("serial")
// note that class names should begin with an upper-case letter
public class ChildFrame extends JDialog {
String test;
JTextField name;
JButton ok, cancel;
public ChildFrame(JFrame parentFrame) {
// the true parameter makes this modal
super(parentFrame, "child frame", true);
Now this dialog window will freeze program flow from the calling code as soon as the dialog is set visible, and the calling code flow won't resume until this dialog is no longer visible.
Also, please have a look at The Use of Multiple JFrames, Good/Bad Practice?
An alternative to this is to continue to use multiple JFrames (not recommended!!), and add a WindowListener to the "child" window, listening for windows closing events, and then getting the information from your dialog in call-back method that is activated when the windows closing event occurs.
For a working example:
import java.awt.BorderLayout;
import java.awt.Window;
import java.awt.Dialog.ModalityType;
import java.awt.event.*;
import javax.swing.*;
#SuppressWarnings("serial")
public class ParentGuiPanel extends JPanel {
private DefaultListModel<String> listModel = new DefaultListModel<>();
private JList<String> jList = new JList<>(listModel);
private JButton addButton = new JButton("Add");
private JDialog childDialog;
private ChildGuiPanel childPanel = new ChildGuiPanel();
public ParentGuiPanel() {
listModel.addElement("Test 1");
listModel.addElement("Test 2");
jList.setPrototypeCellValue("ABCDEFGHIJKLMNOPQRSTUVWXYZ");
jList.setVisibleRowCount(8);
JScrollPane scrollPane = new JScrollPane(jList);
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
addButton.addActionListener(e -> addActionPerformed(e));
addButton.setMnemonic(KeyEvent.VK_A);
JPanel buttonPanel = new JPanel();
buttonPanel.add(addButton);
setLayout(new BorderLayout());
add(scrollPane);
add(buttonPanel, BorderLayout.PAGE_END);
}
private void addActionPerformed(ActionEvent e) {
Window window = null;
if (childDialog == null) {
window = SwingUtilities.getWindowAncestor(this);
if (window == null) {
return;
}
childDialog = new JDialog(window, "Child GUI", ModalityType.APPLICATION_MODAL);
childDialog.add(childPanel);
childDialog.pack();
childDialog.setLocationRelativeTo(window);
}
if (childDialog != null) {
childDialog.setVisible(true);
String text = childPanel.getText();
if (!text.trim().isEmpty()) {
listModel.addElement(text);
}
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
JFrame mainGui = new JFrame("Main GUI");
mainGui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ParentGuiPanel mainPanel = new ParentGuiPanel();
mainGui.add(mainPanel);
mainGui.pack();
mainGui.setLocationRelativeTo(null);
mainGui.setVisible(true);
});
}
}
#SuppressWarnings("serial")
class ChildGuiPanel extends JPanel {
private JTextField textField = new JTextField(15);
private JButton okButton = new JButton("OK");
private JButton cancelButton = new JButton("Cancel");
public ChildGuiPanel() {
okButton.addActionListener(e -> okActionPerformed(e));
cancelButton.addActionListener(e -> cancelActionPerformed(e));
textField.addActionListener(e -> okActionPerformed(e));
okButton.setMnemonic(KeyEvent.VK_O);
cancelButton.setMnemonic(KeyEvent.VK_C);
add(new JLabel("Text: "));
add(textField);
add(okButton);
add(cancelButton);
}
public String getText() {
return textField.getText();
}
private void disposeWindow() {
textField.selectAll();
Window window = SwingUtilities.getWindowAncestor(this);
if (window != null) {
window.dispose();
}
}
private void okActionPerformed(ActionEvent e) {
disposeWindow();
}
private void cancelActionPerformed(ActionEvent e) {
textField.setText("");
disposeWindow();
}
}

Calling method from one class in other

I know that this kind of issue has been discussed here many times, but I'm confused. I'm totally beginner in Java and I honestly don't know what to do and I admit that I don't have that much time to read whole documentation provided by Oracle. Here's my problem:
I'm trying to program a GUI for my program that will be show interference of acoustic waves. Mathematical functionality doesn't matter in here. I've got two classes called Window and Sliders. Window is intended to be a 'main GUI class' and Sliders is supposed to inherit (?) from it.
This comes from another issue that I need to implement ActionListener in class Window and ChangeListener in Sliders class. I heard that one class can't implement several classes that's why I made two.
Now, I wrote a little bit chaotic those two classes, but I don't know how to combine them. It's really silly, but after C++ I'm pretty confused how to tell the program that it is supposed to show in one frame either buttons defined in Window class and sliders defined in Sliders class. Currently it shows only buttons I want to make it showing sliders too.
I'm very sorry for chaotic pseudo code, please help. Please, try to explain as simply as you can/possible. Please feel free to ignore overrided methods, they're not finished yet.
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.*;
public class Window extends JFrame implements ActionListener
{
private JButton showChord, playSound, getSample, getPlot;
private JLabel chordInfo;
private JPanel basicFunctions;
public Window()
{
init();
}
private void init()
{
setVisible(true);
setSize(new Dimension(1000,500));
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
basicFunctions = new JPanel();
FlowLayout basicLayout = new FlowLayout();
basicFunctions.setLayout(basicLayout);
showChord = new JButton("Akord");
playSound = new JButton("Odtwórz");
getSample = new JButton("Pobierz dźwięk");
getPlot = new JButton("Pobierz wykres");
showChord.addActionListener(this);
playSound.addActionListener(this);
getSample.addActionListener(this);
getPlot.addActionListener(this);
basicFunctions.add(showChord);
basicFunctions.add(playSound);
basicFunctions.add(getSample);
basicFunctions.add(getPlot);
add(basicFunctions);
Sliders param = new Sliders();
}
public static void main(String[] args)
{
Window frame = new Window();
}
//Action Listener
#Override
public void actionPerformed(ActionEvent a)
{
Object event = a.getSource();
if(event == showChord)
{
}
else if(event == playSound)
{
}
else if(event == getSample)
{
}
else if(event == getPlot)
{
}
}
}
import java.awt.*;
import javax.swing.event.ChangeEvent;
import javax.swing.*;
import javax.swing.event.ChangeListener;
public class Sliders extends Window implements ChangeListener
{
private JPanel sliders, sliderSub;
private JTextField accAmplitude, accFrequency, accPhase;
private JSlider amplitude, frequency, phase;
private double amplitudeValue, frequencyValue, phaseValue;
public Sliders()
{
sliders = new JPanel();
sliders.setLayout(new FlowLayout());
amplitude = new JSlider(0,100,0);
amplitude.setMajorTickSpacing(10);
amplitude.setMinorTickSpacing(5);
amplitude.setPaintTicks(true);
amplitude.setPaintLabels(true);
frequency = new JSlider(0,10,0);
frequency.setMajorTickSpacing(1);
frequency.setMinorTickSpacing(1/10);
frequency.setPaintTicks(true);
frequency.setPaintLabels(true);
phase = new JSlider(0,1,0);
phase.setMinorTickSpacing(2/10);
phase.setPaintTicks(true);
phase.setPaintLabels(true);
accAmplitude = new JTextField();
accFrequency = new JTextField();
accPhase = new JTextField();
sliders.add(amplitude, BorderLayout.NORTH);
sliders.add(frequency, BorderLayout.CENTER);
sliders.add(phase, BorderLayout.SOUTH);
add(sliders);
}
#Override
public void stateChanged(ChangeEvent arg0)
{
}
}
I've done this so far, but those text fields just stopped showing sliders values and I don't know why. They are defined in the Parameters class and Window class. Can someone help? Additionally in the future I'd like to make those text fields editable so that you can set slider value by typing it in the text field.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.BevelBorder;
import javax.swing.event.*;
public class Window extends JPanel
{
private JMenuBar mainMenu = new JMenuBar();
private Plot plot = new Plot();
private Parameters param = new Parameters();
private JComboBox chooseChord = new JComboBox();
private JButton playSound = new JButton("Odtwórz");
private JButton getSample = new JButton("Pobierz dźwięk");
private JButton getPlot = new JButton("Pobierz wykres");
private JPanel mainPanel = new JPanel();
private JPanel subPanel = new JPanel();
private JPanel buttonsPanel = new JPanel();
private JPanel slidersPanel = new JPanel();
private JLabel chord = new JLabel("Akord:");
private JTextField aValue = new JTextField();
private JTextField fValue = new JTextField();
private JTextField pValue = new JTextField();
public Window()
{
mainPanel.setLayout(new FlowLayout());
buttonsPanel.setLayout(new BoxLayout(buttonsPanel, BoxLayout.Y_AXIS));
slidersPanel.setLayout(new BorderLayout());
subPanel.setLayout(new BorderLayout());
chooseChord.addItem("A");
chooseChord.addItem("A#");
chooseChord.addItem("Ab");
chooseChord.addItem("B");
chooseChord.addItem("Bb");
chooseChord.addItem("C");
chooseChord.addItem("C#");
chooseChord.addItem("Cb");
chooseChord.addItem("D");
chooseChord.addItem("D#");
chooseChord.addItem("E");
chooseChord.addItem("F");
chooseChord.addItem("F#");
buttonsPanel.add(chord);
buttonsPanel.add(chooseChord);
buttonsPanel.add(Box.createRigidArea(new Dimension(0,10)));
buttonsPanel.add(playSound);
buttonsPanel.add(Box.createRigidArea(new Dimension(0,10)));
buttonsPanel.add(getSample);
buttonsPanel.add(Box.createRigidArea(new Dimension(0,10)));
buttonsPanel.add(getPlot);
buttonsPanel.setBorder(BorderFactory.createTitledBorder("Menu"));
slidersPanel.add(param);
JMenu langMenu = new JMenu("Język");
mainMenu.add(langMenu);
subPanel.add(buttonsPanel, BorderLayout.NORTH);
subPanel.add(slidersPanel, BorderLayout.SOUTH);
mainPanel.add(subPanel);
mainPanel.add(plot);
add(mainPanel);
param.addAmplitudeListener(new ChangeListener()
{
public void stateChanged(ChangeEvent a)
{
double ampValue = param.getAmplitudeValue();
aValue.setText(String.valueOf(ampValue));
}
}
);
param.addFrequencyListener(new ChangeListener()
{
public void stateChanged(ChangeEvent f)
{
double frValue = param.getFrequencyValue();
fValue.setText(String.valueOf(frValue));
}
}
);
param.addPhaseListener(new ChangeListener()
{
public void stateChanged(ChangeEvent p)
{
double phValue = param.getPhaseValue();
pValue.setText(String.valueOf(phValue));
}
}
);
}
public JMenuBar getmainMenu()
{
return mainMenu;
}
private static void GUI()
{
Window mainPanel = new Window();
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.setJMenuBar(mainPanel.getmainMenu());
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
GUI();
}
}
);
}
}
class Parameters extends JPanel
{
private JPanel pane = new JPanel();
private JPanel ampPanel = new JPanel();
private JPanel frPanel = new JPanel();
private JPanel phPanel = new JPanel();
private JSlider amplitude = new JSlider(0,100,0);
private JSlider frequency = new JSlider(0,10000,0);
private JSlider phase = new JSlider(0,180,0);
private JLabel pLabel = new JLabel("Faza");
private JLabel aLabel = new JLabel("Amplituda (dB)");
private JLabel fLabel = new JLabel("Częstotliwość (Hz)");
private JTextField preciseAmplitude = new JTextField(3);
private JTextField preciseFrequency = new JTextField(4);
private JTextField precisePhase = new JTextField(3);
public Parameters()
{
preciseAmplitude.setEditable(true);
preciseFrequency.setEditable(true);
precisePhase.setEditable(true);
pane.setLayout(new BoxLayout(pane, BoxLayout.PAGE_AXIS));
ampPanel.setLayout(new FlowLayout());
frPanel.setLayout(new FlowLayout());
phPanel.setLayout(new FlowLayout());
amplitude.setMajorTickSpacing(10);
amplitude.setMinorTickSpacing(5);
amplitude.setPaintTicks(true);
amplitude.setPaintLabels(true);
frequency.setMajorTickSpacing(2000);
frequency.setMinorTickSpacing(100);
frequency.setPaintTicks(true);
frequency.setPaintLabels(true);
phase.setMajorTickSpacing(2/10);
phase.setPaintTicks(true);
phase.setPaintLabels(true);
setBorder(BorderFactory.createTitledBorder("Parametry fali"));
ampPanel.add(aLabel);
ampPanel.add(preciseAmplitude);
pane.add(ampPanel);
pane.add(Box.createRigidArea(new Dimension(0,5)));
pane.add(amplitude);
pane.add(Box.createRigidArea(new Dimension(0,10)));
frPanel.add(fLabel);
frPanel.add(preciseFrequency);
pane.add(frPanel);
pane.add(Box.createRigidArea(new Dimension(0,5)));
pane.add(frequency);
pane.add(Box.createRigidArea(new Dimension(0,10)));
phPanel.add(pLabel);
phPanel.add(precisePhase);
pane.add(phPanel);
pane.add(Box.createRigidArea(new Dimension(0,5)));
pane.add(phase);
pane.add(Box.createRigidArea(new Dimension(0,10)));
add(pane);
}
public int getAmplitudeValue()
{
return amplitude.getValue();
}
public int getFrequencyValue()
{
return frequency.getValue();
}
public int getPhaseValue()
{
return phase.getValue();
}
public void addAmplitudeListener(ChangeListener ampListener)
{
amplitude.addChangeListener(ampListener);
}
public void addFrequencyListener(ChangeListener frListener)
{
frequency.addChangeListener(frListener);
}
public void addPhaseListener(ChangeListener phListener)
{
phase.addChangeListener(phListener);
}
}
class Plot extends JPanel
{
private JPanel componentWave = new JPanel();
private JPanel netWave = new JPanel();
private JLabel componentLabel = new JLabel("Fale składowe");
private JLabel netLabel = new JLabel("Fala wypadkowa");
private JLabel wave = new JLabel("Wybierz falę składową");
private JPanel labels = new JPanel();
private JComboBox chooseWave = new JComboBox();
public Plot()
{
labels.setLayout(new BoxLayout(labels, BoxLayout.PAGE_AXIS));
componentWave.setBackground(new Color(255,255,255));
netWave.setBackground(new Color(255,255,255));
componentWave.setBorder(BorderFactory.createBevelBorder(BevelBorder.LOWERED));
netWave.setBorder(BorderFactory.createBevelBorder(BevelBorder.LOWERED));
componentWave.setPreferredSize(new Dimension(400,200));
netWave.setPreferredSize(new Dimension(400,200));
labels.add(wave);
labels.add(Box.createRigidArea(new Dimension(0,10)));
labels.add(chooseWave);
labels.add(componentLabel);
labels.add(componentWave);
labels.add(Box.createRigidArea(new Dimension(0,20)));
labels.add(netLabel);
labels.add(netWave);
add(labels);
}
}

Window is intended to be a 'main GUI class' and Sliders is supposed to inherit (?) from it.
Nope: this is a misuse of inheritance and will only lead to problems since the Windows instance that Sliders inherently is, is completely distinct from the displayed Windows instance. What you need to do is to pass references.
For example, the following code uses outside classes for the JButton and JMenuItem Actions (Actions are like ActionListeners on steroids), and uses a class that holds a JSlider that allows itside classes to attach listeners to the slider.
import java.awt.Component;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import javax.swing.*;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
public class Foo extends JPanel {
private static final long serialVersionUID = 1L;
private Action helloAction = new HelloAction("Hello", KeyEvent.VK_H);
private Action exitAction = new ExitAction("Exit", KeyEvent.VK_X);
private JMenuBar menuBar = new JMenuBar();
private JTextField sliderValueField = new JTextField(10);
private Bar bar = new Bar();
public Foo() {
sliderValueField.setEditable(false);
sliderValueField.setFocusable(false);
add(new JButton(helloAction));
add(new JButton(exitAction));
add(new JLabel("Slider Value: "));
add(sliderValueField);
add(bar);
JMenu fileMenu = new JMenu("File");
fileMenu.setMnemonic(KeyEvent.VK_F);
fileMenu.add(new JMenuItem(exitAction));
fileMenu.add(new JMenuItem(helloAction));
menuBar.add(fileMenu);
bar.addSliderListener(new ChangeListener() {
#Override
public void stateChanged(ChangeEvent e) {
int sliderValue = bar.getSliderValue();
sliderValueField.setText(String.valueOf(sliderValue));
}
});
}
public JMenuBar getJMenuBar() {
return menuBar;
}
private static void createAndShowGui() {
Foo mainPanel = new Foo();
JFrame frame = new JFrame("Foo");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.setJMenuBar(mainPanel.getJMenuBar());
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
class HelloAction extends AbstractAction {
public HelloAction(String name, int mnemonic) {
super(name); // sets name property and gives button its title
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(null, "Hello!");
}
}
class ExitAction extends AbstractAction {
private static final long serialVersionUID = 1L;
public ExitAction(String name, int mnemonic) {
super(name);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
Component component = (Component) e.getSource();
Window win = SwingUtilities.getWindowAncestor(component);
if (win == null) {
// if no window, then a JMenuItem held in a JPopupMenu
JPopupMenu popup = (JPopupMenu) component.getParent();
component = popup.getInvoker();
win = SwingUtilities.getWindowAncestor(component);
}
win.dispose();
}
}
class Bar extends JPanel {
private JSlider slider = new JSlider(0, 100, 50);
public Bar() {
slider.setPaintLabels(true);
slider.setPaintTicks(true);
slider.setMajorTickSpacing(20);
slider.setMinorTickSpacing(5);
slider.setSnapToTicks(true);
setBorder(BorderFactory.createTitledBorder("Slider Panel"));
add(slider);
}
public int getSliderValue() {
return slider.getValue();
}
// one way to let outside classes listen for changes
public void addSliderListener(ChangeListener listener) {
slider.addChangeListener(listener);
}
}
You ask about decimal labels, and yes this can be done but requires use of a label table. For example,
JSlider slider = new JSlider(0, 100, 50);
slider.setPaintLabels(true);
slider.setPaintTicks(true);
slider.setMajorTickSpacing(20);
slider.setMinorTickSpacing(2);
Dictionary<Integer, JLabel> labels = new Hashtable<>();
for (int i = 0; i <= 100; i += 20) {
labels.put(i, new JLabel(String.format("%.1f", i / 200.0)));
}
slider.setLabelTable(labels);
Which displays as:
You would also have to translate the value back from int to its corresponding floating point number.

How to declare just one

I have the following working code with two buttons as event listeners. One button to get and display a Panel panel1 and the other to get and display another Panel panel2 removing the existing displayed panel. I created two actionPerformed methods for each button to carry out each other's tasks. I just want to make one to shorten the code but I don't know how to detect which button in a panel is displaying at compile time. Any help will be appreciated.
//Switching between panels (screens)
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ScreenDemo extends JFrame {
private JPanel panel1, panel2;
private JButton btn1, btn2;
JLabel label1 = new JLabel("Screen 1");
JLabel label2 = new JLabel("Screen 2");
public ScreenDemo() {
createPanel(); //Created at Line 14
addPanel(); //Created at Line 28
}
private void createPanel() {
//Panel for first screen
panel1 = new JPanel(new FlowLayout());
btn1 = new JButton("Move to Screen 2");
btn1.addActionListener(new addScreen1ButtonListener());
//Panel for second screen
panel2 = new JPanel(new FlowLayout());
btn2 = new JButton("Move to Screen 1");
btn2.addActionListener(new addScreen2ButtonListener());
}
private void addPanel() {
panel1.add(label1);
panel1.add(btn1);
panel2.add(label2);
panel2.add(btn2);
add(panel1); //Add the first screen panel
}
class addScreen1ButtonListener implements ActionListener {
public void actionPerformed(ActionEvent ae) {
getContentPane().removeAll();
getContentPane().add(panel2);
repaint();
printAll(getGraphics()); //Prints all content
}
}
class addScreen2ButtonListener implements ActionListener {
public void actionPerformed(ActionEvent ea) {
getContentPane().removeAll();
getContentPane().add(panel1);
repaint();
printAll(getGraphics()); //Prints all content
}
}
public static void main(String[] args) {
ScreenDemo screen = new ScreenDemo();
screen.setTitle("Switching Screens");
screen.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
screen.setSize(500, 500);
screen.setVisible(true);
}
}

implement ActionListener for your class, and try this code
ScreenDemo extends JFrame implements ActionListener
...
btn1.addActionListener(this);
btn2.addActionListener(this);
...
#override
public void actionPerformed(ActionEvent ae) {
if(ae.getSource().equals(btn1)) {
...
}
else if(ae.getSource().equals(btn1)) {
...
}
}

you have to implements the class from ActionListener
than register JButton like : btn.addActionListener(this);
so close now, You just need to capture the event and get the source from where it is called like:
public void actionPerformed(ActionEvent ae) {
if(ae.getSource == btn1){
//shuffle panel from btn1
}
if(ae.getSource == btn2) {
//shuffle panel from btn2
}
}

jbutton changes text of text field

I am simply trying to make an employee clock. I have a keypad of numbers 0-9 and a text field. I want to be able to click the numbers and the numbers will appear on the text field. This seems so easy but I can't find any answers for it.
I'm using netbeans and I created the design of the Jframe in the Design.
I added action events to all of the buttons.
I'm calling each button like Btn0 (the button with 0 on it, Btn1, etc etc.

You need to retrieve the JButton on which ActionEvent is fired and then append the text retrieved from the JButton to the JTextField. Here is the short Demo:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
class EClock extends JFrame
{
JTextField tf;
public void createAndShowGUI()
{
setTitle("Eclock");
Container c = getContentPane();
tf = new JTextField(10);
JPanel cPanel = new JPanel();
JPanel nPanel = new JPanel();
nPanel.setLayout(new BorderLayout());
nPanel.add(tf);
cPanel.setLayout(new GridLayout(4,4));
for (int i =0 ; i < 10 ; i++)
{
JButton button = new JButton(String.valueOf(i));
cPanel.add(button);
button.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent evt)
{
String val = ((JButton)evt.getSource()).getText();
tf.setText(tf.getText()+val);
}
});
}
c.add(cPanel);
c.add(nPanel,BorderLayout.NORTH);
setSize(200,250);
setLocationRelativeTo(null);
setResizable(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
EClock ec = new EClock();
ec.createAndShowGUI();
}
});
}
}

Add action listener on your button first (double click on button in GUI Designer :) ):
button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
//Set text by calling setText() method for your textfield
textfield.setText("Desired text");
}
});
Regards.

Create an Action that can be shared by all the buttons. Something like:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;
public class ButtonCalculator extends JFrame implements ActionListener
{
private JButton[] buttons;
private JTextField display;
public ButtonCalculator()
{
display = new JTextField();
display.setEditable( false );
display.setHorizontalAlignment(JTextField.RIGHT);
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout( new GridLayout(0, 5) );
buttons = new JButton[10];
for (int i = 0; i < buttons.length; i++)
{
String text = String.valueOf(i);
JButton button = new JButton( text );
button.addActionListener( this );
button.setMnemonic( text.charAt(0) );
button.setBorder( new LineBorder(Color.BLACK) );
buttons[i] = button;
buttonPanel.add( button );
}
getContentPane().add(display, BorderLayout.NORTH);
getContentPane().add(buttonPanel, BorderLayout.SOUTH);
setResizable( false );
}
public void actionPerformed(ActionEvent e)
{
JButton source = (JButton)e.getSource();
display.replaceSelection( source.getActionCommand() );
}
public static void main(String[] args)
{
ButtonCalculator frame = new ButtonCalculator();
frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
frame.pack();
frame.setLocationRelativeTo( null );
frame.setVisible(true);
}
}

I know nothing of netbeans, however, a search on google gave me this
Netbeans GUI Functionality
it seems to have the data needed, give it a read and no doubt you can figure out what needs to be amended for it to suit your purposes

How to add JPanel by clicking JButton?

I'm trying to create a small GUI, it has 2 JButtons, and 2 JPanels with some drawing animation on each of them. By default it must show first JPanel, and by clicking on second JButton I want to see my second JPanel. So : I create JFrame, Panel1 and Panel2, where I have drawn my animations, create Button1 and Button2 and adding to them ActionListeners. I have also MainPanel which has in a fields variable i. By changing this "i" my constructor adds to MainPanel either Panel1 (default) or Panel2 (by clicking on JButton2 I change i). Than I add this MainPanel to my frame. So my question : in the class MainPanel I have refreshMe method, what should I write there to make my GUI working properly? Thanks. Here is my code:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class GuiTest {
public static void main(String[] args) {
JFrame f = new JFrame();
MainPanel myPanel = new MainPanel();
f.add(myPanel);
Button1 button1 = new Button1();
Button2 button2 = new Button2();
myPanel.add(button1);
myPanel.add(button2);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.pack();
f.setVisible(true);
}
}
class MainPanel extends JPanel {
Panel1 p1 = new Panel1();
Panel2 p2 = new Panel2();
public int i = 1; //this is being changed later by clicking JButton
// I use this setter later in actionPerformed in order to change i
public void setI(int i) {
this.i = i;
}
MainPanel() {
if (i == 1) {
this.add(p1);
}
if (i == 2) {
this.add(p2);
}
}
public void refreshMe() {
// Need some help here:
// I don't know what should I write, how to make a repaint of myPanel?
System.out.println("just test, if the method refreshMe working by clicking some button");
}
}
class Panel1 extends JPanel {
public Panel1() {
this.setBackground(Color.BLUE);
// a lot of drawing stuff going on here
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
class Panel2 extends JPanel {
public Panel2() {
this.setBackground(Color.GREEN);
// a lot of drawing stuff going on here
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
class Button1 extends JButton {
MainPanel someObj1 = new MainPanel();
Button1() {
setText("Show Annimation A");
addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
someObj1.setI(1);
System.out.println("The variable i is now: " + someObj1.i);
someObj1.refreshMe();
}
});
}
}
class Button2 extends JButton {
MainPanel someObj2 = new MainPanel();
Button2() {
setText("Show Annimation B");
addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
someObj2.setI(2);
System.out.println("The variable i is now: " + someObj2.i);
someObj2.refreshMe();
}
});
}
}

In order to reflect changes after adding/removing or resizing a component that is on a visible container call revalidate() and repaint() on the containers instance after adding/removing or resizing the component.
Though this will not work in your code the main reason being inside JButton classes you recreate a new instance of MainPanel when in fact the 2 JButtons should share the single instance which is being used (you could pass MainPanel instance to the JButtons constructors, but you shouldn't really be extending a JButton unless adding custom functionality):
class Button2 extends JButton {
MainPanel someObj2 = new MainPanel();//you create an instance of MainPanel which isnt even showing and than do changes on that, this way you will never see any of the changes
Button2() {
}
}
A few other suggestions on your code:
Dont extend JButton class unnecessarily, simply create an instance of JButton like you did with JFrame and call methods on JButton instance.
Dont forget to create/manipulate Swing components on Event Dispatch Thread, via SwingUtilities.invokeLater(..) block, read here for more.
Here is your code fixed (above suggestions ect implemented):
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class Test {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame f = new JFrame();
final MainPanel myPanel = new MainPanel();
f.add(myPanel);
JButton button1 = new JButton("Show Animation A");
JButton button2 = new JButton("Show Animation B");
button1.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
myPanel.setI(1);
System.out.println("The variable i is now: " + myPanel.i);
myPanel.refreshMe();
}
});
button2.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
myPanel.setI(2);
System.out.println("The variable i is now: " + myPanel.i);
myPanel.refreshMe();
}
});
myPanel.add(button1);
myPanel.add(button2);
myPanel.checkPanel();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.pack();
f.setVisible(true);
}
});
}
}
class MainPanel extends JPanel {
Panel1 p1 = new Panel1();
Panel2 p2 = new Panel2();
public int i = 1; //this is being changed later by clicking JButton
// I use this setter later in actionPerformed in order to change i
public void setI(int i) {
this.i = i;
}
public void refreshMe() {
checkPanel();
revalidate();
repaint();
// Need some help here:
// I don't know what should I write, how to make a repaint of myPanel?
System.out.println("just test, if the method refreshMe working by clicking some button");
}
public void checkPanel() {
if (i == 1) {
this.add(p1);
this.remove(p2);//or it will remain there as this is default flowlayout
} else if (i == 2) {
this.add(p2);
this.remove(p1);
}
}
}
class Panel1 extends JPanel {
public Panel1() {
this.setBackground(Color.BLUE);
// a lot of drawing stuff going on here
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
class Panel2 extends JPanel {
public Panel2() {
this.setBackground(Color.GREEN);
// a lot of drawing stuff going on here
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
However Id suggest something simpler, fortunately you have 2 choices:
1) Use CardLayout which will allow you to flip between multiple components on a single JFrame/container.
Here is an example I made:
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class Test {
private final static String PANEL1 = "panel 1";
private final static String PANEL2 = "panel 2";
public Test() {
initComponents();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Test();
}
});
}
private void initComponents() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel1 = new JPanel();
panel1.add(new JLabel("Panel 1"));
JPanel panel2 = new JPanel();
panel2.add(new JLabel("Panel 2"));
//Create the panel that contains the "cards".
final JPanel cards = new JPanel(new CardLayout());
cards.add(panel1, PANEL1);
cards.add(panel2, PANEL2);
//create button to allow chnage to next card
JButton buttonNext = new JButton(">");
buttonNext.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
CardLayout cl = (CardLayout) (cards.getLayout());//get cards
cl.next(cards);
}
});
//create button to allow chnage to previous card
JButton buttonPrev = new JButton("<");
buttonPrev.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
CardLayout cl = (CardLayout) (cards.getLayout());//get cards
cl.previous(cards);
}
});
//create panel to hold buttons which will allow switching between cards
JPanel buttonPanel = new JPanel();
buttonPanel.add(buttonPrev);
buttonPanel.add(buttonNext);
frame.add(cards);
frame.add(buttonPanel, BorderLayout.SOUTH);
frame.pack();
frame.setVisible(true);
}
}
2) Use removeAll() technique i.e call frame.getContentPane().removeAll() which will remove all components currently on JFrame and than add the new content and call revalidate() and repaint() (also might want to add pack() in there) on JFrame instance to reflect changes. Though Id recommend CardLayout.

I think you can just use CardLayout to implement your function. Please refer to here