Develop Reference

Modifying a jPanel using buttons on another jPanel

I've just approached Java and I'm working on a project for my University class.
I'm working on a Milionaire game but I'm stuck.
I've got a JFrame class in which I have 2 panels. The first one is made of buttons, the second one is the panel I want to change by pressing the buttons. Buttons have their own class with their constructor and the same is for the panels cause they have a different layout. I need to create a method in the button class to remove the second panel from the frame and add a third panel (described in another more JPanel class). So I technically need to acess from button class method to my JFrame class constructor. Is there a way to do it?
I've got my first Panel class and my Button class with its ClickListener method.
Now I need to know how can i modify my JFrame class in my Button method to close the first Panel at click, opening in the same position another one.
Button Method
public class ClickListenerD1 implements ActionListener
{
public void actionPerformed(ActionEvent event)
{
buttonPressed();
}
private void buttonPressed()
{
JPanel panel3 = new Domanda1();
}
}
Main JFrame class
package nuovaPartita;
import java.awt.BorderLayout;
import java.awt.Color;
import javax.swing.JFrame;
import javax.swing.JPanel;
/**
* Visualizza la finestra di gioco.
*/
public class NuovaPartitaViewer extends JFrame
{
private static final int FRAME_LUNGH = 1600;
private static final int FRAME_ALT = 900;
JPanel panel1 = new NuovaPartitaComp1();
JPanel panel2 = new Start();
/**
* Costruisce una finestra di gioco su cui vengono visualizzati due
pannelli.
*/
public NuovaPartitaViewer()
{
setSize(FRAME_LUNGH, FRAME_ALT);
setTitle("CHI VUOL ESSER MILIONARIO?");
setVisible(true);
setLocationRelativeTo(null);
setResizable(false);
BorderLayout layout = new BorderLayout();
getContentPane().setLayout(layout);
getContentPane().setBackground(Color.BLACK);
add(panel1, BorderLayout.WEST);
add(panel2, BorderLayout.CENTER);
}
}
Thanks

You can just set the panel corresponding to a button in the button's action listener.
public class NuovaPartitaViewer extends JFrame {
public NuovaPartitaViewer() {
JPanel p1 = new JPanel();
p1.add(new JLabel("Panel 1"));
JPanel p2 = new JPanel();
p2.add(new JLabel("Panel 2"));
JPanel p3 = new JPanel();
p3.add(new JLabel("Panel 3"));
JPanel p4 = new JPanel();
p4.add(new JLabel("Panel 4"));
JButton b1 = new JButton("Button 1");
b1.addActionListener(e -> setPanel(p1));
JButton b2 = new JButton("Button 2");
b2.addActionListener(e -> setPanel(p2));
JButton b3 = new JButton("Button 3");
b3.addActionListener(e -> setPanel(p3));
JButton b4 = new JButton("Button 4");
b4.addActionListener(e -> setPanel(p4));
JPanel buttonsPanel = new JPanel(new GridLayout(2, 2));
buttonsPanel.add(b1);
buttonsPanel.add(b2);
buttonsPanel.add(b3);
buttonsPanel.add(b4);
BorderLayout layout = new BorderLayout();
getContentPane().setLayout(layout);
getContentPane().setBackground(Color.BLACK);
add(buttonsPanel, BorderLayout.WEST);
add(p1, BorderLayout.CENTER);
setTitle("CHI VUOL ESSER MILIONARIO?");
pack();
setLocationRelativeTo(null);
setResizable(false);
setVisible(true);
}
private void setPanel(JPanel p) {
add(p, BorderLayout.CENTER);
revalidate();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> new NuovaPartitaViewer());
}
}
If all your buttons are customized (extends JButton) then you can add the action listener code directly in that class. Pass the corresponding JPanel in the constructor so you can use it in the action listener.
Additionally:
Don't set the size of the frame, use pack() instead.
Call setVisible(true) as the last thing you do in the method.

Content is being add horizontally to JScrollPane

im starting to work with java Swing and i was trying to make a system to show something like a Map :
But when i try to add another entry to the JSCrollPane it's being added horizontally intead of vertically, i have tried everything i don't what i mithgt be doing wrong but i can't manage do fix it.
Here i create the Frame :
JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.setResizable(false);
JPanel panel = new JPanel();
final JPanel content = new JPanel();
new DataEntry("", 0).create(content);
final JScrollPane scrollPane = new JScrollPane(content, JScrollPane.VERTICAL_SCROLLBAR_ALWAYS, JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
scrollPane.setWheelScrollingEnabled(true);
panel.add(scrollPane);
scrollPane.setMinimumSize(new Dimension(400, 60));
final JButton add = new JButton("Add");
add.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
new DataEntry("", 0).create(content);
}
});
panel.add(add);
frame.setContentPane(panel);
frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
frame.pack();
frame.setVisible(true);
And this is how i create the Entry :
public JPanel create(final JPanel content) {
final JPanel panel = new JPanel();
final JPanel fields = new JPanel();
fields.add(new JLabel("Variable"));
fields.add(variable);
fields.add(new JLabel("Row"));
fields.add(row);
panel.add(fields);
JButton remove = new JButton("Remove");
remove.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
content.remove(panel);
content.revalidate();
}
});
panel.add(remove);
content.add(panel, BorderLayout.CENTER);
content.revalidate();
return panel;
}
At the start i was wondering why it wasn't displaying any new Entry, then i tried changing HORIZONTAL_SCROLLBAR_NEVER > HORIZONTAL_SCROLLBAR_AS_NEEDED and then i realized that the variables were being add horizontally.
Here is a gif to see what's going on (Couldn't manage to take a proper photo) : GIF

BorderLayout not working JFrame

For some reason I can't get the BorderLayout to set the way it's supposed to. Just would like to know where I'm going wrong.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ColorFactory extends JFrame
{
final int width = 500;
final int height = 300;
private JPanel buttonPanel;
private JPanel radioButtonPanel;
private JLabel msgChangeColor;
public ColorFactory()
{
setTitle("Color Factory");
setSize(width, height);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new BorderLayout());
createTopPanel();
add(buttonPanel, BorderLayout.NORTH);
createBottomPanel();
add(radioButtonPanel, BorderLayout.SOUTH);
msgChangeColor = new JLabel("Top buttons change the panel color and bottom radio buttons change the text color.");
add(msgChangeColor, BorderLayout.CENTER);
pack();
}
private void createTopPanel()
{
buttonPanel = new JPanel();
setLayout(new FlowLayout());
JButton redButton = new JButton("Red");
redButton.setBackground(Color.RED);
redButton.addActionListener(new ButtonListener());
redButton.setActionCommand("R");
JButton orangeButton = new JButton("Orange");
orangeButton.setBackground(Color.ORANGE);
orangeButton.addActionListener(new ButtonListener());
orangeButton.setActionCommand("O");
JButton yellowButton = new JButton("Yellow");
yellowButton.setBackground(Color.YELLOW);
yellowButton.addActionListener(new ButtonListener());
yellowButton.setActionCommand("Y");
buttonPanel.add(redButton);
buttonPanel.add(orangeButton);
buttonPanel.add(yellowButton);
}
private void createBottomPanel()
{
radioButtonPanel = new JPanel();
setLayout(new FlowLayout());
JRadioButton greenRadioButton = new JRadioButton("Green");
greenRadioButton.setBackground(Color.GREEN);
greenRadioButton.addActionListener(new RadioButtonListener());
greenRadioButton.setActionCommand("G");
JButton blueRadioButton = new JButton("Blue");
blueRadioButton.setBackground(Color.BLUE);
blueRadioButton.addActionListener(new RadioButtonListener());
blueRadioButton.setActionCommand("B");
JButton cyanRadioButton = new JButton("Cyan");
cyanRadioButton.setBackground(Color.CYAN);
cyanRadioButton.addActionListener(new RadioButtonListener());
cyanRadioButton.setActionCommand("C");
radioButtonPanel.add(greenRadioButton);
radioButtonPanel.add(blueRadioButton);
radioButtonPanel.add(cyanRadioButton);
}
private class ButtonListener implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
String actionColor = e.getActionCommand();
if(actionColor.equals("R"))
{
buttonPanel.setBackground(Color.RED);
radioButtonPanel.setBackground(Color.RED);
}
if(actionColor.equals("O"))
{
buttonPanel.setBackground(Color.ORANGE);
radioButtonPanel.setBackground(Color.ORANGE);
}
if(actionColor.equals("Y"))
{
buttonPanel.setBackground(Color.YELLOW);
radioButtonPanel.setBackground(Color.YELLOW);
}
}
}
private class RadioButtonListener implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
String actionTextColor = e.getActionCommand();
if(actionTextColor.equals("G"))
{
msgChangeColor.setForeground(Color.GREEN);
}
if(actionTextColor.equals("B"))
{
msgChangeColor.setForeground(Color.BLUE);
}
if(actionTextColor.equals("C"))
{
msgChangeColor.setForeground(Color.CYAN);
}
}
}
public static void main(String[] args)
{
ColorFactory run = new ColorFactory();
run.setVisible(true);
}
}

The problem is you are changing the layout manager for the frame when you create your top and bottom panels...
private void createTopPanel() {
buttonPanel = new JPanel();
setLayout(new FlowLayout()); // <--- This is call setLayout on the frame
This is why it's dangerous to...
Extend from something like JFrame directly...
Dynamically build components
It's all to easy to lose context and start effecting components you didn't actually want to...

Another problem (besides the one posted by MadProgrammer) is that you add your components to the JFrame itself.
You should add content to the content pane of the frame which you can get by calling JFrame.getContentPane().
Example:
JFrame f = new JFrame("Test");
Container c = f.getContentPane();
c.add(new JButton("In Center"), BorderLayout.CENTER);
c.add(new JButton("At the Bottom"), BorderLayout.SOUTH);
c.add(new JButton("At the Top"), BorderLayout.NORTH);
c.add(new JButton("On the Left"), BorderLayout.WEST);
c.add(new JButton("On the Right"), BorderLayout.EAST);
You can set/change the content panel by calling JFrame.setContentPane(). The default content panel already has BorderLayout so you don't even need to change it nor to set a new panel.

How to set component size inside container with BoxLayout

I'm facing a problem with using BoxLayout.
In my example, I try to decrease the height of the text field and change the width of the buttons (as shown in green marker in the picture at the bottom). I know about the techniques setPreferredSize() and setMaximumSize(), but it did not work as it should. The line add(Box.createHorizontalGlue()) also did not help.
Thanks for any ideas.
public class Testy extends JPanel {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
constructGUI();
}
});
}
private static void constructGUI() {
JFrame frame = new JFrame("Testy");
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
JPanel centerPanel = new JPanel();
centerPanel.setBackground(Color.DARK_GRAY);
centerPanel.setPreferredSize(new Dimension(100, 400));
frame.add(centerPanel, BorderLayout.CENTER);
Testy eastPanel = new Testy();
frame.add(eastPanel, BorderLayout.EAST);
frame.pack();
frame.setVisible(true);
}
public Testy() {
setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
JButton button = new JButton("Button ...... 1");
//button.setPreferredSize(...);
//button.setMaximumSize(...);
add(button);
button = new JButton("Button 2");
//button.setPreferredSize(...);
//button.setMaximumSize(...);
add(button);
button = new JButton("Button ........... 3");
//button.setPreferredSize(...);
//button.setMaximumSize(...);
add(button);
JLabel label = new JLabel("Label");
//label.setPreferredSize(...);
//label.setMaximumSize(...);
add(label);
JTextField textField = new JTextField();
//textField.setPreferredSize(...);
//textField.setMaximumSize(...);
add(textField);
button = new JButton("Button 4");
//button.setPreferredSize(...);
//button.setMaximumSize(...);
add(button);
//add(Box.createHorizontalGlue());
}
}

First you have to realize that component position and size in Java Swing depends on Layout manager (if layout manager is set) not on the component itself. The component requests the manager for size.
For this case I would use different layout - combination of GridLayout and BorderLayout is enough and very simple and straightforward. But if want use BoxLayout, then...
Documentation says:
BoxLayout pays attention
to a component's requested minimum, preferred, and maximum sizes.
While you are fine-tuning the layout, you might need to adjust these
sizes. ... For example, a button's maximum size is generally the
same as its preferred size. If you want the button to be drawn wider
when additional space is available, then you need to change its
maximum size.
Then set components maximum size: c.setMaximumSize(new Dimension(Integer.MAX_VALUE, c.getMinimumSize().height)); (c means button, label and textField in your example)
Edit 1:
Here is working source code:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;
public class Testy extends JPanel {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
constructGUI();
}
});
}
private static void constructGUI() {
JFrame frame = new JFrame("Testy");
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
JPanel centerPanel = new JPanel();
centerPanel.setBackground(Color.DARK_GRAY);
centerPanel.setPreferredSize(new Dimension(100, 400));
frame.add(centerPanel, BorderLayout.CENTER);
Testy eastPanel = new Testy();
frame.add(eastPanel, BorderLayout.EAST);
frame.pack();
frame.setVisible(true);
}
public Testy() {
setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
JButton button = new JButton("Button ...... 1");
//button.setPreferredSize(...);
button.setMaximumSize(new Dimension(Integer.MAX_VALUE, button.getMinimumSize().height));
add(button);
button = new JButton("Button 2");
//button.setPreferredSize(...);
button.setMaximumSize(new Dimension(Integer.MAX_VALUE, button.getMinimumSize().height));
add(button);
button = new JButton("Button ........... 3");
//button.setPreferredSize(...);
button.setMaximumSize(new Dimension(Integer.MAX_VALUE, button.getMinimumSize().height));
add(button);
JLabel label = new JLabel("Label");
//label.setPreferredSize(...);
label.setMaximumSize(new Dimension(Integer.MAX_VALUE, label.getMinimumSize().height));
add(label);
JTextField textField = new JTextField();
//textField.setPreferredSize(...);
textField.setMaximumSize(new Dimension(Integer.MAX_VALUE, textField.getMinimumSize().height));
add(textField);
button = new JButton("Button 4");
//button.setPreferredSize(...);
button.setMaximumSize(new Dimension(Integer.MAX_VALUE, button.getMinimumSize().height));
add(button);
// add(Box.createVerticalGlue());
}
}
Edit 2:
If you want laid out Button 4 at the bottom of right column add this line add(Box.createVerticalGlue()); between add(textField); and button = new JButton("Button 4");.

As a quick remedy, you can use nested layouts, in the sense, that on the right side, create a JPanel with BorderLayout, put a JPanel(say compPanel) at the CENTER and a JPanel(say buttonPanel) at PAGE_END location. Now use a new JPanel(say panel) with GridLayout and put all the components on it, and place this compPanel inside centerPanel. Place JButton(button4) inside buttonPanel as is.
BoxLayout on the contrary, respects the preferred size of a given JComponent, which is usually calculated based on the content the JComponent holds or given explicity, hence components do not tend to align well with respect to other given components.
Here is the working example :
import java.awt.*;
import javax.swing.*;
public class Testy extends JPanel {
private JPanel panel;
private JPanel buttonPanel;
public Testy() {
setLayout(new BorderLayout(5, 5));
JPanel compPanel = new JPanel();
panel = new JPanel(new GridLayout(6, 1, 5, 5));
JButton button = new JButton("Button ...... 1");
//button.setPreferredSize(...);
//button.setMaximumSize(...);
panel.add(button);
button = new JButton("Button 2");
//button.setPreferredSize(...);
//button.setMaximumSize(...);
panel.add(button);
button = new JButton("Button ........... 3");
//button.setPreferredSize(...);
//button.setMaximumSize(...);
panel.add(button);
JLabel label = new JLabel("Label");
//label.setPreferredSize(...);
//label.setMaximumSize(...);
panel.add(label);
JTextField textField = new JTextField();
//textField.setPreferredSize(...);
//textField.setMaximumSize(...);
panel.add(textField);
compPanel.add(panel);
buttonPanel = new JPanel();
button = new JButton("Button 4");
buttonPanel.add(button);
add(compPanel, BorderLayout.CENTER);
add(buttonPanel, BorderLayout.PAGE_END);
}
private void constructGUI() {
JFrame frame = new JFrame("Testy");
frame.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
JPanel centerPanel = new JPanel();
frame.getContentPane().setLayout(new BorderLayout(5, 5));
centerPanel.setBackground(Color.DARK_GRAY);
frame.add(centerPanel, BorderLayout.CENTER);
frame.add(this, BorderLayout.LINE_END);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Testy().constructGUI();
}
});
}
}
OUTPUT :

This should get close, based on your draw, just need to work on that component
below the JLabel (using setPreferredSize()):
JPanel main = new JPanel(new GridLayout(1, 2));
JPanel left = new JPanel();
//left.setPreferredSize(some size);
JPanel right = new JPanel(new GridLayout(6, 1));
//right.setPreferredSize(some size);
right.add(new JButton("Button 1"));
//...
right.add(new JButton("Button 4"));
main.add(left);
main.add(right);

Calling a JPanel inside a split panel Java

Hi I'm having trouble in my code. I can't call or display my JPanel(TruthTable) inside my splitpane in the Minimize class when I click the button and Keypressed(Enter).The problem is in the class Minimize
*UPDATE: I'have solved my problem regarding to diplaying the panel my next problem is when I call the constructor the text in the panel should be updated.I also change the setText to append 'coz they say that JPanel doesnt support setText.I've already used,validate,repaint method but no luck in updating the textArea.
Heres my code for class Minimize:
package splashdemo;
public class Minimize extends JPanel implements ClipboardOwner
{
simButton.addActionListener(new ActionListener()
{ public void actionPerformed(ActionEvent ae)
{
LogicGates lg= new LogicGates();
lg.geth();
sim s=new sim();
s.InputExp(lg.g,lg.g1);
s.menu();
s.setSize(700,700);
s.setVisible(false);
Frame f = new Frame();
Panel panel = new Panel();
f.add(BorderLayout.SOUTH, panel);
f.add(BorderLayout.CENTER, new sim());
f.add(BorderLayout.SOUTH, panel);
f.setSize(580, 500);
panel.add(s.button);
f.show();
f.setVisible(false);
JOptionPane.showMessageDialog(null, b);
ex=b;
cAppend();
JOptionPane.showMessageDialog(null, ex1);
InToPost(ex1);
foutput= doTrans();
JOptionPane.showMessageDialog(null, foutput);
TruthTable_1 kl = new TruthTable_1(foutput);
Minimize mi = new Minimize();
s.InputExp(lg.g,lg.g1);
s.menu();
lg.gatessplit = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, mi, lg.p1);
//here's the splitpane where I should display the TruthTable_1 panel but it doesn't diplay
lg.p1.add(lg.gatessplit = new JSplitPane(JSplitPane.VERTICAL_SPLIT, s,kl));
lg.gatessplit.setOneTouchExpandable(true);
lg.gatessplit.setDividerLocation(250);
lg.gatessplit.setPreferredSize(new Dimension(900, 500));
lg.createAndShowGUI();
}});
}
Heres my code the TruthTable_1:constructors
public TruthTable_1() {
super();
tableArea.append("This is a Test");
//setBackground(Color.black);
createg();
setVisible(true);
}
public void createg(){
setLayout(new BorderLayout());
line= 0;
truth= 'T';
fallacy= 'F';
final JPanel top= new JPanel();
input= new TextField(35);
TFCheck= new Checkbox("Select for \"1/0\" (default\"T/F\")");
check= new JButton("Check");
check.addActionListener(this);
top.add(input);
top.add(TFCheck);
top.add(check);
top.setVisible(false);
tableArea= new JTextArea(16, 40);
tableArea.setEditable(false);
tableArea.setFont(new Font("Lucida Console", Font.PLAIN, 14));
// all letters are the same width in this font
go= new JButton("Do it to it!");
go.addActionListener(this);
input.addActionListener(this);
go.setVisible(false);
add(top, BorderLayout.NORTH);
scrolls= new JScrollPane(tableArea);// add scroll buttons to the area
add(scrolls, BorderLayout.CENTER);
add(go, BorderLayout.SOUTH);
setSize(535, 500);
//setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLocation(100, 100);
}
public TruthTable_1(String f){
createg();
tableArea.append(run(f));
}