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Java Swing GridLayout

I am making a GUI application, and I made a JPanel with JScrollPane. The problem is that when adding elements to it, first few elements taking all available space, which looks ugly. How can I prevent them from that?
Here is the code:
import javax.swing.*;
import java.awt.*;
public class VersionPanel extends JPanel {
private final JPanel panel;
public VersionPanel() {
this.setLayout(new BorderLayout());
this.panel = new JPanel(new GridLayout(0, 1));
JScrollPane scrollPane = new JScrollPane(this.panel);
scrollPane.setPreferredSize(new Dimension(400, 300));
this.add(scrollPane, BorderLayout.CENTER);
}
public void addVersionLabel(VersionLabel label) {
this.panel.add(label);
this.panel.revalidate();
int height = (int) this.panel.getPreferredSize().getHeight();
this.panel.scrollRectToVisible(new Rectangle(0, height, 10, 10));
}
}
Here is the code of VersionLabel:
import javax.swing.*;
import javax.swing.border.BevelBorder;
import java.awt.*;
import java.awt.event.ActionListener;
public class VersionLabel extends JPanel {
private final ActionListener launch;
private final ActionListener delete;
private final ActionListener install;
public VersionLabel(String versionNumber, boolean installed, ActionListener launch, ActionListener delete, ActionListener install) {
this.launch = launch;
this.delete = delete;
this.install = install;
this.setLayout(new GridLayout(1, 2));
this.add(this.getLeftPanel(versionNumber, installed));
this.add(this.getRightPanel(installed));
this.setBorder(new BevelBorder(BevelBorder.RAISED, Color.RED, Color.RED)); //test border
this.setMaximumSize(this.getMinimumSize());
}
private JPanel getLeftPanel(String versionNumber, boolean installed) {
return new JPanel() {{
this.setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
this.add(new JLabel(versionNumber));
this.add(new JLabel(installed ? "Installed" : "Not Installed"));
}};
}
private JPanel getRightPanel(boolean installed) {
return new JPanel(new FlowLayout(FlowLayout.RIGHT)) {{
if(installed) {
this.add(new JButton("Launch") {{ this.addActionListener(launch); }});
this.add(new JButton("Delete") {{ this.addActionListener(delete); }});
} else {
this.add(new JButton("Install") {{ this.addActionListener(install); }});
}
}};
}
}

Thanks to #DontKnowMuchButGettingBetter! I added a new JPanel to my code:
public VersionPanel() {
this.setLayout(new BorderLayout());
this.panel = new JPanel(new GridLayout(0, 1));
JPanel bPanel = new JPanel(new BorderLayout());
bPanel.add(this.panel, BorderLayout.PAGE_START);
JScrollPane scrollPane = new JScrollPane(bPanel);
scrollPane.setPreferredSize(new Dimension(400, 300));
this.add(scrollPane, BorderLayout.CENTER);
}

How to pass JTextfield info from a JDialog into a JFrame (separate classes)

I have been trying to pass the info of my JTextField that is in a JDialog into my JFrame. Both the JDialog and JFrame are in separate classes. I have tried to store the JTextField into a JLable using the .setText and .getText and then passing the JLable into the JFrame but with no luck.
I know there are many similar questions but I have tried many different approaches but still no luck. I am relatively new to Java and do not know all the in's and out's. Any help is very appreciated!
My code for the JFrame:
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.JPanel;
public class StockApp extends JFrame implements PropertyChangeListener {
private JPanel main = new JPanel();
private JPanel north = new JPanel();
private JPanel center = new JPanel();
private JPanel south = new JPanel();
private JButton buyStock = new JButton("Buy Stock");
private JButton sellStock = new JButton("Sell Stock");
public TestTest variables = new TestTest();
private JLabel stockNameNorth = new JLabel("Stock Name");
private JLabel stockPriceNorth = new JLabel("Stock Price");
String stockName = variables.getStockName();
String stockPrice = variables.getStockPrice();
public StockApp() {
setTitle("StockApp");
getContentPane().setBackground(Color.white);
setSize(400,400);
setLocation(500,200);
setVisible(true);
main.setLayout(new BorderLayout());
north.setLayout(new FlowLayout());
center.setLayout(new FlowLayout());
south.setLayout(new FlowLayout());
stockNameNorth.setText(stockName);
stockPriceNorth.setText(stockPrice);
add(main);
north.add(stockNameNorth);
north.add(stockPriceNorth);
south.add(buyStock);
south.add(sellStock);
main.add(north, BorderLayout.NORTH);
main.add(center, BorderLayout.CENTER);
main.add(south, BorderLayout.SOUTH);
}
}
And Dialog:
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class TestTest extends JDialog implements ActionListener {
private JPanel main = new JPanel();
private JPanel north = new JPanel();
private JPanel center = new JPanel();
private JPanel south = new JPanel();
private JLabel stockNameLabel = new JLabel("Stock name: ");
private JLabel stockPriceLabel = new JLabel("Stock price(£): ");
private JTextField stockNameIn = new JTextField(5);
private JTextField stockPriceIn = new JTextField(5);
private JButton buttonOK = new JButton("OK");
public JLabel stockPrice = new JLabel();
public JLabel stockName = new JLabel();
public TestTest() {
getContentPane().setBackground(Color.white);
setSize(400,400);
setLocation(500,200);
setModal(false);
setVisible(true);
getRootPane().setDefaultButton(buttonOK);
main.setLayout(new BorderLayout());
north.setLayout(new FlowLayout());
center.setLayout(new FlowLayout());
south.setLayout(new FlowLayout());
add(main);
north.add(stockNameLabel);
north.add(stockNameIn);
center.add(stockPriceLabel);
center.add(stockPriceIn);
south.add(buttonOK);
main.add(north, BorderLayout.NORTH);
main.add(center, BorderLayout.CENTER);
main.add(south, BorderLayout.SOUTH);
buttonOK.addActionListener(this);
}
public void actionPerformed(ActionEvent e) {
if (e.getSource() == buttonOK){
stockName.setText(stockNameIn.getText());
stockPrice.setText(stockPriceIn.getText());
dispose();
new StockApp();
}
}
public String getStockName() {
return stockNameIn.getText();
}
public String getStockPrice() {
return stockPriceIn.getText();
}
}
I am trying to pass the stockName and stockPrice variables from the JDialog into the JFrame. I then want the name and price to display at the top of the JFrame.

For demonstration, what the problem is, we need less Fields and Buttons.
So far, no component of StockApp needs to be accessed from different methods, so there is no need to make them visible outside of the ctor.
More explanations in the code.
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JPanel;
public class StockApp extends JFrame {
public StockApp() {
// move those unreferenced panels here, so we don't have to reason about them:
JPanel main = new JPanel();
JPanel north = new JPanel();
JPanel center = new JPanel();
JPanel south = new JPanel();
// add price later, when name works
JButton buyStock = new JButton("Buy Stock");
JLabel stockNameNorth = new JLabel("Stock Name");
// critical change: Make the label, which you like to update,
// accessible by whom it should be updated:
TestTest variables = new TestTest (stockNameNorth);
setTitle ("StockApp");
getContentPane().setBackground(Color.white);
setSize (600,400);
setLocation (500,200);
setVisible (true);
// make the close-frame action terminate the program:
setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
main.setLayout (new BorderLayout());
north.setLayout (new FlowLayout());
center.setLayout (new FlowLayout());
south.setLayout (new FlowLayout());
add (main);
north.add (stockNameNorth);
south.add (buyStock);
main.add (north, BorderLayout.NORTH);
main.add (center, BorderLayout.CENTER);
main.add (south, BorderLayout.SOUTH);
}
// Main method to start the damn thing
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new StockApp ();
}
});
}
}
// no need to make this class public in a short test:
class TestTest extends JDialog implements ActionListener {
// this are elements, visible outside the construction phase,
// we need to have access to from more than one method.
// Make this important distinction visible to the reader:
JLabel name;
JTextField stockNameIn = new JTextField (5);
JButton buttonOK = new JButton ("OK");
// add the JLabel to update to the ctor, so that it can't be forgotten
// to be set
public TestTest (JLabel pname) {
// we copy the reference to the label, to have access to it in
// the actionPerformed method.
name = pname;
JPanel main = new JPanel();
JPanel north = new JPanel();
JPanel center = new JPanel();
JPanel south = new JPanel();
JLabel stockNameLabel = new JLabel ("Stock name: ");
getContentPane().setBackground(Color.white);
// different size/location than frame, so that they don't hide
// each other completly
setSize (400,600);
setLocation (700,300);
setModal (false);
setVisible (true);
getRootPane().setDefaultButton(buttonOK);
main.setLayout (new BorderLayout());
north.setLayout (new FlowLayout());
center.setLayout (new FlowLayout());
south.setLayout (new FlowLayout());
add (main);
north.add (stockNameLabel);
north.add (stockNameIn);
south.add (buttonOK);
main.add (north, BorderLayout.NORTH);
main.add (center, BorderLayout.CENTER);
main.add (south, BorderLayout.SOUTH);
buttonOK.addActionListener(this);
}
// here we need access to the button - was it the OK-Button, clicked?
// and the textfield stockNameIn, to read the text
// and the name field from the frame, to set the text
public void actionPerformed(ActionEvent e) {
if (e.getSource () == buttonOK) {
name.setText (stockNameIn.getText());
dispose();
}
}
}

How to set Jbuttons to a specific place when you have a background in JLabel : code below

How to set Jbuttons to a specific place when you have a background in JLabel : code below
i can't get the jlabel to stay at the top and the buttons to stay south(bottom) ??
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ButtonsClass extends JFrame
implements ActionListener {
JButton b1 = new JButton("button1");
JButton b2 = new JButton("button2");
JButton b3 = new JButton("button3");
JButton b4 = new JButton("button4");
JLabel label = new JLabel("buttons:");
public static void main(String[] args) {
new ButtonsClass();
}
public Jukebox() {
setLayout(new BorderLayout());
setContentPane(new JLabel(new ImageIcon("image.png")));
setLayout(new FlowLayout());
setSize(500,150);
setTitle("Backgroundwithbuttons");
setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE);
JPanel top = new JPanel();
top.add(label);
add("North", top);
JPanel bottom = new JPanel();
bottom.add(b1);
bottom.add(b2);
bottom.add(b3);
bottom.add(b4);
add("South", bottom);
setVisible(true);
}
}

" i can't get the jlabel to stay at the top and the buttons to stay south(bottom)"
That's because you set the layout the BorderLayout, then immediately set it to FlowLayout. With FlowLayout, your BorderLayout positioning will do nothing.
setLayout(new BorderLayout());
setContentPane(new JLabel(new ImageIcon("image.png")));
setLayout(new FlowLayout());
Just get rid of the setLayout(new FlowLayout());
Also your constructor is wrong
public Jukebox() {
-Should be-
public ButtonClass() {
Also you need to set the layout of the JLabel that you set as the content pane. Yout constructor should look like this
public ButtonClass() {
JLabel background = new JLabel(new ImageIcon("image.png"));
background.setLayout(new BorderLayout());
setContentPane(background);
setTitle("Background with buttons");
setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE);
JPanel top = new JPanel();
top.add(label);
add(top, BorderLayout.NORTH);
JPanel bottom = new JPanel();
bottom.add(b1);
bottom.add(b2);
bottom.add(b3);
bottom.add(b4);
add(bottom, BorderLayout.SOUTH);
//pack();
setVisible(true);
}
Also, add("North", top); is a deprecated method. Instead use add(top, BorderLayout.NORTH) and same for add(bottom, BorderLayout.SOUTH)
Also, Swing apps should be run on the Event Dispatch Thread. You can do so by wrapping the code in your main with a SwingUtilities.invokeLater...
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new ButtonClass();
}
});
}
Also, you should set the panel's opaque property to false, if you want the image to show behind them.
top.setOpaque(false);
bottom.setOpaque(false);
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ButtonClass extends JFrame
implements ActionListener {
JButton b1 = new JButton("button1");
JButton b2 = new JButton("button2");
JButton b3 = new JButton("button3");
JButton b4 = new JButton("button4");
JLabel label = new JLabel("buttons:");
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new ButtonClass();
}
});
}
public ButtonClass() {
label.setForeground(Color.WHITE);
JLabel background = new JLabel(new ImageIcon(getClass().getResource("/resources/space.png")));
background.setLayout(new BorderLayout());
setContentPane(background);
setTitle("Background with buttons");
setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE);
JPanel top = new JPanel();
top.setOpaque(false);
top.add(label);
add(top, BorderLayout.NORTH);
JPanel bottom = new JPanel();
bottom.setOpaque(false);
bottom.add(b1);
bottom.add(b2);
bottom.add(b3);
bottom.add(b4);
add(bottom, BorderLayout.SOUTH);
setSize(400, 300);
setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {}
}

Try using:
add(bottom, BorderLayout.SOUTH);
instead of:
add("South", bottom);
BorderLayout tutorial

Dynamically add components to a JDialog on button click

I want to know how to add components dynamically to a JDialog. I know there is a similar question on SO here, but as you can see, I have his solution as a part of my code.
So the idea is that on click of the button, I need to add a component on the dialog. The sample code is below:
import java.awt.Container;
import java.awt.Dialog;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class Test extends JFrame {
/**
*
*/
private static final long serialVersionUID = 1L;
public static void main(String args[]) {
Test test = new Test();
test.createDialog();
}
public void createDialog() {
DynamicDialog dialog = new DynamicDialog(this);
dialog.setSize(300, 300);
dialog.setVisible(true);
}
}
class DynamicDialog extends JDialog {
/**
*
*/
private static final long serialVersionUID = 1L;
public DynamicDialog(final JFrame owner) {
super(owner, "Dialog Title", Dialog.DEFAULT_MODALITY_TYPE);
final JPanel mainPanel = new JPanel();
mainPanel.setLayout(new BoxLayout(mainPanel, BoxLayout.Y_AXIS));
final JPanel panel = new JPanel();
panel.setLayout(new BoxLayout(panel, BoxLayout.X_AXIS));
panel.add(Box.createRigidArea(new Dimension(3, 10)));
panel.add(createLabel("Click on add"));
panel.add(Box.createRigidArea(new Dimension(23, 10)));
panel.add(createLabel("To add another line of text"));
panel.add(Box.createHorizontalGlue());
mainPanel.add(panel);
mainPanel.add(Box.createRigidArea(new Dimension(3, 10)));
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new BoxLayout(buttonPanel, BoxLayout.Y_AXIS));
buttonPanel.add(Box.createHorizontalGlue());
JButton button = new JButton();
button.setText("Add another line");
buttonPanel.add(button);
mainPanel.add(buttonPanel);
mainPanel.add(Box.createRigidArea(new Dimension(3, 10)));
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
Container contentPane = owner.getContentPane();
JPanel _panel = new JPanel();
_panel.setLayout(new BoxLayout(_panel, BoxLayout.X_AXIS));
_panel.add(Box.createHorizontalGlue());
_panel.add(createLabel("Added!"));
contentPane.add(_panel);
contentPane.validate();
contentPane.repaint();
owner.pack();
}
});
pack();
setLocationRelativeTo(owner);
this.add(mainPanel);
}
JLabel createLabel(String name) {
JLabel label = new JLabel(name);
return label;
}
}

If you add it to the main panel it will work, you were adding it to the content pane of the frame which it seems it does not show up anywhere.
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
JPanel _panel = new JPanel();
_panel.setLayout(new BoxLayout(_panel, BoxLayout.X_AXIS));
_panel.add(Box.createHorizontalGlue());
_panel.add(createLabel("Added!"));
mainPanel.add(_panel);
mainPanel.validate();
mainPanel.repaint();
owner.pack();
}
})

Java swing; How to toggle panel's visibility?

i made this code to navigate trough panel1 and panel2
with buttons.
(button1 and button2) but when i run my code the frame stays empty.
Can somebody explain me what i'm doing wrong and how i can accomplish
toggling between panel1 and panel2 in this way? Starting with panel1 first
Code:
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JFrame;
public class togglepanel {
public static void main(String[] args) {
final JFrame frame = new JFrame();
final JPanel panel1 = new JPanel();
final JPanel panel2 = new JPanel();
JButton button1 = new JButton("previous frame!");
JButton button2 = new JButton("next frame");
frame.setLocationRelativeTo(null);
frame.setResizable(true);
frame.setVisible(true);
frame.setSize(600, 400);
frame.add(panel1);
frame.add(panel2);
panel1.add(button2);
panel1.setVisible(true);
panel2.add(button1);
panel2.setVisible(false);
button1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
panel1.setVisible(true);
panel2.setVisible(false);
}
});
button2.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
panel1.setVisible(false);
panel2.setVisible(true);
}
});
}
}
thanks in advance

Use a layout manager.
frame.setLayout(new FlowLayout());

Another useful way to do this, and I think better is to use a CardLayout and to add both JPanels to a container that uses this CardLayout. You can then easily swap views by calling the CardLayout methods.
e.g.,
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class TogglePanel {
public static void main(String[] args) {
final CardLayout cardlayout = new CardLayout();
final JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
final Container contentPane = frame.getContentPane();
contentPane.setLayout(cardlayout);
final JPanel panel1 = new JPanel();
final JPanel panel2 = new JPanel();
JButton button1 = new JButton("previous frame!");
JButton button2 = new JButton("next frame");
contentPane.setPreferredSize(new Dimension(600, 400));
contentPane.add(panel1, "Panel 1");
contentPane.add(panel2, "Panel 2");
frame.pack();
frame.setLocationRelativeTo(null);
frame.setResizable(true);
frame.setVisible(true);
panel1.add(button2);
panel2.add(button1);
ActionListener btnListener = new ActionListener() {
public void actionPerformed(ActionEvent e) {
cardlayout.next(contentPane);
}
};
button1.addActionListener(btnListener);
button2.addActionListener(btnListener);
}
}