Java panel alignment - java

class CipherGUIFrame extends JFrame {
public CipherGUIFrame() {
super("Caesar Cipher GUI");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(400, 600);
JTextArea area1 = new JTextArea();
JTextArea area2 = new JTextArea();
JSpinner myspinner=new JSpinner();
JPanel mainframe = new JPanel();
mainframe.setLayout(new BoxLayout(mainframe, BoxLayout.Y_AXIS));
JPanel p1 = new JPanel();
JPanel p2 = new JPanel();
JPanel p3 = new JPanel();
p1.setLayout(new BoxLayout(p1, BoxLayout.Y_AXIS));
p2.setLayout(new BoxLayout(p2, BoxLayout.Y_AXIS));
p1.setBorder(BorderFactory.createTitledBorder("Cleartext"));
p2.setBorder(BorderFactory.createTitledBorder("Spinner"));
p3.setLayout(new BoxLayout(p3, BoxLayout.Y_AXIS));
p3.setBorder(BorderFactory.createTitledBorder("Ciphertext"));
p1.add(area1);
p2.add(myspinner);
p3.add(area2);
mainframe.add(p1);
mainframe.add(p2);
mainframe.add(p3);
this.add(mainframe);
}
}
It seems that this code produces something which looks similar to this:
I am trying to tidy this up so it looks cleaner; is there a way to shrink the middle panel or to make the others bigger to make it look nicer?

Don't set the sizes of anything, but instead set the columns and rows of your JTextAreas. Don't use BoxLayout when you don't want its behaviors. Put your JTextAreas in JScrollPanes instead. And don't forget to pack() your JFrame.
import java.awt.BorderLayout;
import javax.swing.*;
public class Cipher2 extends JPanel {
public static final int ROWS = 12;
public static final int COLS = 30;
private JTextArea textArea1 = new JTextArea(ROWS, COLS);
private JTextArea textArea2 = new JTextArea(ROWS, COLS);
public Cipher2() {
setLayout(new BoxLayout(this, BoxLayout.Y_AXIS)); // Box OK here
JScrollPane scroll1 = new JScrollPane(textArea1);
add(wrapComponentWithTitle(scroll1, "Fubar"), BorderLayout.PAGE_START);
add(wrapComponentWithTitle(new JSpinner(), "Spinner"), BorderLayout.CENTER);
scroll1 = new JScrollPane(textArea2);
add(wrapComponentWithTitle(scroll1, "Snafu"), BorderLayout.PAGE_END);
}
private JPanel wrapComponentWithTitle(JComponent component, String title) {
// BoxLayout NOT OK here. Use BorderLayout instead
JPanel wrapPanel = new JPanel(new BorderLayout());
wrapPanel.add(component);
wrapPanel.setBorder(BorderFactory.createTitledBorder(title));
return wrapPanel;
}
private static void createAndShowGui() {
Cipher2 mainPanel = new Cipher2();
JFrame frame = new JFrame("Foo");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}

I figured out the answer: change Y_AXIS to X_AXIS.
<3

Related

ScrollPane not showing on JLabel

When I run this program, I don't see a scrollbar on the Label. What am I missing?
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Util1
{
public static void main(String[] args)
{
new Util1();
}
public Util1()
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new ExamplePane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
protected class ExamplePane extends JPanel
{
public ExamplePane()
{
final JPanel panel = new JPanel(new GridBagLayout());
final JLabel message = new JLabel("<html>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello</html>");
message.setPreferredSize(new Dimension(500, 50));
JScrollPane scroller = new JScrollPane( message, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED, JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
scroller.setViewportView(message);
panel.add(scroller);
add(panel);
}
}
}
To see a scrollbar wrap the "message" JLabel into JPanel and then add this JPanel to JScrollPane like bellow:
public ExamplePane() {
final JPanel panel = new JPanel(new GridBagLayout());
final JLabel message = new JLabel("<html>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello<br>Hello</html>");
message.setPreferredSize(new Dimension(500, 50));
final JPanel messagePanel = new JPanel();
messagePanel.add(message);
JScrollPane scroller = new JScrollPane(messagePanel, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED, JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
scroller.setPreferredSize(new Dimension(100, 50));
panel.add(scroller);
add(panel);
}

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

JButtons in JPanel in another JPanel

Is it possible to add a JPanel with JButtons to a Split JPanel? Right now, I have the JPanel with JButtons added to a JFrame, but I want it on a JPanel with other JPanels. When I attempt to do this, I get a completely blank JPanel with dividers.
______________________________________________________________________________
public class Panel extends JPanel implements Runnable, ActionListener {
public Panel(){
JFrame frame = new JFrame();
ctsMenu = new JPanel(new GridLayout(2,2));
ctsMenu.setPreferredSize(new Dimension(500,500));
for (int iRows = 0; iRows < 2 ; iRows++){
for (int iColumns = 0; iColumns < 2; iColumns++){
sGrid[iRows][iColumns] = new JButton ("("+iRows+","+iColumns+")");
ctsMenu.add(sGrid[iRows][iColumns]);
sGrid[iRows][iColumns].addActionListener(this);
panel.add(ctsMenu);
}
}
sGrid[0][0].setText("A");
sGrid[0][1].setText("B");
sGrid[1][0].setText("C");
sGrid[1][1].setText("D");
frame.setContentPane(panel);
frame.pack();
frame.setVisible(true);
}}
____________________________________________________________________
public MainFrame()
{
setTitle( "Split Pane Application" );
setBackground( Color.GREEN );
JPanel topPanel = new JPanel();
topPanel.setLayout( new BorderLayout() );
getContentPane().add( topPanel );
createPanel1();
createPanel2();
createPanel3();
createPanel4();
splitPaneV = new JSplitPane( JSplitPane.VERTICAL_SPLIT );
topPanel.add( splitPaneV, BorderLayout.CENTER );
splitPaneV.setDividerLocation(300);
splitPaneV.setLeftComponent( gamePanel);
// gamePanel.addKeyListener(new KeyListener());
gamePanel.setFocusable(true);
gamePanel.requestFocusInWindow();
splitPaneV.setRightComponent( panel3 );
}
}
public void createPanel1(){
// deleted to take up less space
}
public void createPanel2(){
// deleted to take up less space
}
public void createPanel3(){
panel3 = new Panel();
}
public void createPanel4(){
//deleted to take up less space
}
}
You ask:
Is it possible to add a JPanel with JButtons to a Split JPanel?
Yes, it is most definitely possible to do this. It's something similar to what we do all the time:
import javax.swing.*;
public class SplitPaneEg {
private static void createAndShowGui() {
JPanel panel1 = new JPanel();
panel1.setBorder(BorderFactory.createTitledBorder("Panel 1"));
panel1.add(new JButton("Button 1"));
panel1.add(new JButton("Button 2"));
JPanel panel2 = new JPanel();
panel2.setBorder(BorderFactory.createTitledBorder("Panel 2"));
panel2.add(new JButton("Button 1"));
panel2.add(new JButton("Button 2"));
JSplitPane splitPane = new JSplitPane(JSplitPane.VERTICAL_SPLIT, panel1,
panel2);
JFrame frame = new JFrame("Split Pane Example");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(splitPane);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
You state:
Right now, I have the JPanel with JButtons added to a JFrame, but I want it on a JPanel with other JPanels. When I attempt to do this, I get a completely blank JPanel with dividers.
Then you have an error in your code, but unfortunately based on code you've posted I doubt that any of us can do more than just guess. If you need more specific help, then you will want to post a small runnable example that demonstrates your problem, an sscce.

Keep BoxLayout From Expanding Children

I want to stack some JComponents vertically inside a JPanel so they stack at the top and any extra space is at the bottom. I'm using a BoxLayout. The components will each contain a JTextArea that should allow the text to wrap if necessary. So, basically, I want the height of each of these components to be the minimum necessary for displaying the (possibly wrapped) text.
Here's a contained code example of what I'm doing:
import javax.swing.*;
import java.awt.*;
public class TextAreaTester {
public static void main(String[] args){
new TextAreaTester();
}
public TextAreaTester(){
JFrame frame = new JFrame();
JPanel panel = new JPanel();
panel.setLayout(new BoxLayout(panel,BoxLayout.PAGE_AXIS));
panel.setPreferredSize(new Dimension(100,400));
for(int i = 0; i<3; i++){
JPanel item = new JPanel(new BorderLayout());
JTextArea textarea = new JTextArea("this is a line of text I want to wrap if necessary");
textarea.setWrapStyleWord(true);
textarea.setLineWrap(true);
textarea.setMaximumSize( textarea.getPreferredSize() );
item.add(textarea,BorderLayout.NORTH);
panel.add(item);
}
panel.add(Box.createGlue());
frame.add(panel);
frame.setVisible(true);
frame.pack();
}
}
The child JPanels are expanding to fill the vertical space. I tried using glue because I thought that's what glue was for, but it seems to do nothing at all. Any help?
Note: I have found questions that look almost identical, but none with answers I can apply.
One solution: nest JPanels with the outer JPanel using Borderlayout and adding the BoxLayout using JPanel to this one BorderLayout.NORTH, also known as BorderLayout.PAGE_START:
Edit for Kleopatra:
import javax.swing.*;
import java.awt.*;
public class TextAreaTester {
public static void main(String[] args) {
new TextAreaTester();
}
public TextAreaTester() {
JFrame frame = new JFrame();
JPanel panel = new JPanel();
panel.setLayout(new BoxLayout(panel, BoxLayout.PAGE_AXIS));
// panel.setPreferredSize(new Dimension(100,400));
for (int i = 0; i < 3; i++) {
JPanel item = new JPanel(new BorderLayout());
// item.setLayout(new BoxLayout(item,BoxLayout.LINE_AXIS));
JTextArea textarea = new JTextArea(
"this is a line of text I want to wrap if necessary", 3, 35);
textarea.setWrapStyleWord(true);
textarea.setLineWrap(true);
// textarea.setMaximumSize(textarea.getPreferredSize());
// item.setMaximumSize( item.getPreferredSize() );
item.add(new JScrollPane(textarea), BorderLayout.NORTH);
panel.add(item);
}
panel.add(Box.createGlue());
JPanel mainPanel = new JPanel(new BorderLayout()) {
private final int prefW = 100;
private final int prefH = 400;
#Override
public Dimension getPreferredSize() {
return new Dimension(prefW, prefH);
}
};
// mainPanel.setPreferredSize(new Dimension(100, 400));
mainPanel.add(panel, BorderLayout.PAGE_START);
frame.add(mainPanel);
frame.setVisible(true);
// frame.getContentPane().add(jp);
frame.pack();
}
}
Alternatively, you can use Box.Filler. Just replace your call to panel.add(Box.createGlue()) with
panel.add(new Box.Filler(new Dimension(0, 0),
new Dimension(0, Short.MAX_VALUE),
new Dimension(0, Short.MAX_VALUE)));
If you want to achieve the same for a horizontal layout, just use Short.MAX_VALUE for width instead of height in the Dimension call.

JScrollPane won't work

Hey guys I wanted to create a JScrollPane but it won't work... and I don't know why... here's my code...
public class test extends JFrame{
public test(){
setSize(1000,600);
}
private static JButton[] remove;
private static JPanel p = new JPanel();
public static void main(String[]args){
p.setLayout(null);
JFrame t=new test();
remove = new JButton[25];
for(int i=0;i<25;i++){
remove[i]=new JButton("Remove");
remove[i].setBounds(243,92+35*i,85,25);
p.add(remove[i]);
}
JScrollPane scrollPane = new JScrollPane(p);
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
t.add(scrollPane);
t.setVisible(true);
}
Umm and Im pretty sure the frame isn't big enough for these 25 buttons... But if i delete that p.setLayout(null); A horizontal scroll bar will be created automatically... I don't really know what is wrong with my code... Pls help thank you very much!
You need to set p's preferredSize for this to work.
p.setPreferredSize(new Dimension(800, 2000));
Or you could have p extend JPanel and then override the getPreferredSize() method to return the proper dimension.
And I agree -- get rid of your null layouts. Learn about and use the layout managers if you want to use Swing correctly and have robust Swing GUI's.
e.g.,
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Foo extends JFrame {
private static final int BUTTON_COUNT = 25;
public static void main(String[] args) {
JPanel btnPanel = new JPanel(new GridLayout(0, 1, 0, 20));
btnPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
AbstractAction removeAction = new AbstractAction("Remove") {
#Override
public void actionPerformed(ActionEvent evt) {
JButton src = (JButton) evt.getSource();
JPanel container = (JPanel) src.getParent();
container.remove(src);
container.revalidate();
container.repaint();
}
};
for (int i = 0; i < BUTTON_COUNT; i++) {
JButton removeBtn = new JButton(removeAction);
btnPanel.add(removeBtn);
}
JPanel borderPanel = new JPanel(new BorderLayout());
borderPanel.add(btnPanel, BorderLayout.NORTH);
JScrollPane scrollpane = new JScrollPane(borderPanel,
JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
scrollpane.setPreferredSize(new Dimension(400, 800));
JFrame frame = new JFrame("Foo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(scrollpane);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
The issue is that a scroll pane checks the component inside it for a "preferred size" so a pane with a null layout has a preferred size of (0,0). Which it ignores.
You should do something along the lines of:
p.setPreferredSize(1000,600);
And you should see some scroll bars appear, I'm not sure how accurate they will be though.

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