I'm writing this swing application and I'm using multiple panels in a BoxLayout format, but it seems to be that the empty space between the panels is being divided up between them and it looks really ugly. How do you adjust and customize how much space is put between panels? Sorry if this is a repost; I was unable to find an older post.
import java.awt.*;
import java.awt.datatransfer.Clipboard;
import java.awt.datatransfer.StringSelection;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
class gui extends JFrame implements ActionListener{
JFrame frame = new JFrame("Ark Admin Spawn Commands");
JPanel panel = new JPanel();
JComboBox dinos;
JComboBox corruptedDinos;
public JSlider dinoLevel;
JLabel input;
JLabel dino;
JLabel title;
gui(){
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel mainPanel = new JPanel();
mainPanel.setLayout(new BoxLayout(mainPanel, BoxLayout.Y_AXIS));
JPanel panelOne = new JPanel();
JPanel panelTwo = new JPanel();
JPanel panelThree = new JPanel();
mainPanel.add(panelOne);
mainPanel.add(panelTwo);
mainPanel.add(panelThree);
title = new JLabel("Spawning Dinos");
String[] dinoNames= {"The Island:"};
String[] corruptedDinoNames = {"Extinction:"};
dinos = new JComboBox(dinoNames);
corruptedDinos = new JComboBox(corruptedDinoNames);
dinoLevel = new JSlider(JSlider.HORIZONTAL, 1, 600, 400);
dinoLevel.setMajorTickSpacing(20);
dinoLevel.setPaintTicks(true);
input = new JLabel("Select Level: ");
event e = new event();
dinoLevel.addChangeListener(e);
dinos.addActionListener(this);
corruptedDinos.addActionListener(this);
panelOne.add(title);
panelTwo.add(input);
panelTwo.add(dinoLevel);
panelThree.add(dinos);
panelThree.add(corruptedDinos);
this.getContentPane().add(mainPanel);
this.setTitle("Ark Admin Spawn Commands");
this.setSize(600, 600);
this.setVisible(true);
}
public static void main (String args[]) {
new gui();
}
public class event implements ChangeListener{
#Override
public void stateChanged(ChangeEvent e) {
int value = dinoLevel.getValue();
input.setText("Level: " + value);
}
}
#Override
public void actionPerformed(ActionEvent arg0) {
}
}
but it seems to be that the empty space between the panels is being divided up between them
Correct. A BoxLayout will attempt to allocate extra space to all components.
However, it will respect the maximum size of each panel.
So to prevent the panels height from growing you can use code like:
JPanel panelOne = new JPanel()
{
#Override
public dimension getMaximumSize()
{
Dimension d = getPreferredSize()
d.width = Integer.MAX_VALUE;
return d;
}
};
Or because the default layout manager of the frame is a BorderLayout, you can just use:
//this.getContentPane().add(mainPanel);
add(mainPanel, BorderLayout.PAGE_START); // getContentPane() is not needed
The PAGE_START of the BorderLayout respects the preferred height of the component.
Related
I am trying to resize the center panel of my BorderLayout but the size is not changing. It keeps filling the rest of the frame that is available. I have tried setting the preferred size but has no effect. I would like how size of the frame but only need a portion of the center to be actually a panel for later use.
import javax.swing.*;
import javax.swing.border.Border;
import java.awt.*;
public class Gui extends JFrame {
Border blackline = BorderFactory.createLineBorder(Color.black);
private JPanel board;
private JPanel buttons;
private JButton setMissing, by4, by8;
public Gui(){
setUpGui();
}
public void setUpGui(){
this.setSize(1000,1000);
this.setTitle("Comp361 Assignment One");
addButtons();
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
board = new JPanel();
board.setPreferredSize(new Dimension(400,400));
this.add(board, BorderLayout.CENTER);
//Sboard.setBackground(Color.Gray);
board.setBorder(blackline);
this.setVisible(true);
}
public void addButtons(){
buttons = new JPanel(new FlowLayout());
setMissing = new JButton("Set X");
by4 = new JButton("4 by 4");
by8 = new JButton("8 by 8");
buttons.add(setMissing);
buttons.add(by4);
buttons.add(by8);
this.add(buttons,BorderLayout.PAGE_START);
}
public static void main (String[] args){
new Gui();
}
}
For extra padding around the central panel, you might put it to a panel with GridBagLayout (with no constraint) to center it, then add the GBL panel to the CENTER of the BorderLayout.
I have problem with displaying components on my JFrame. I'm closing my current window and opening new one and want to display jLabel on it but nothing is happening. Code is below :
Frame[] nF = DBChooser.getFrames();
nF[0].setVisible(false);
JFrame windoow = new JFrame("Processing");
JPanel pan = new JPanel();
windoow.setPreferredSize(new Dimension(400, 150));
pan.setPreferredSize(new Dimension(400, 150));
JLabel textLabel = new JLabel ("Processing...");
textLabel.setLayout(null);
pan.setLayout(null);
windoow.setLayout(null);
pan.add(textLabel);
pan.revalidate();
pan.repaint();
windoow.getContentPane().add(pan);
windoow.setLocationRelativeTo(null);
windoow.pack();
windoow.setVisible(true);
I appreciate any help
Why you need so many setLayout(null); ? I remove them and it worked
public class DBChooser extends Frame {
public static void main(String args[]) {
Frame[] nF = DBChooser.getFrames();
// nF[0].setVisible(false);
JFrame windoow = new JFrame("Processing");
JPanel pan = new JPanel();
windoow.setPreferredSize(new Dimension(400, 150));
pan.setPreferredSize(new Dimension(400, 150));
JLabel textLabel = new JLabel("Processing...");
// textLabel.setLayout(null);
// pan.setLayout(null);
// windoow.setLayout(null);
pan.add(textLabel);
pan.revalidate();
pan.repaint();
windoow.getContentPane().add(pan);
windoow.setLocationRelativeTo(null);
windoow.pack();
windoow.setVisible(true);
}
}
It is because you set a null layout to window and panel without specifying any width, lenght or position, either use some LayoutManager or set these properties (eg. bounds). A null LayoutManager means that you need to set everything yourself, because there is nothing (no LayoutManager) that would place your elements automatically. This example uses a BorderLayout, which creates a nice effect:
the code:
import java.awt.BorderLayout;
import java.awt.Dimension;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class Test {
public static void main(String[] args) {
JFrame windoow = new JFrame("Processing");
JPanel pan = new JPanel();
windoow.setPreferredSize(new Dimension(400, 150));
pan.setPreferredSize(new Dimension(400, 150));
JLabel textLabel = new JLabel("Processing...");
textLabel.setLayout(null);
pan.setLayout(new BorderLayout());
windoow.setLayout(new BorderLayout());
pan.add(textLabel);
pan.revalidate();
pan.repaint();
windoow.getContentPane().add(pan);
windoow.setLocationRelativeTo(null);
windoow.pack();
windoow.setVisible(true);
}
}
What would be the best way for me to move the buttons so they are under each other instead of beside each other (see image below)?
The code for this class is as follows. The Main method is in a different class.
package guiplay;
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class MainGUI extends JFrame {
private JButton openReportSelection = new JButton("Open Report Viewer");
private JButton closeButton = new JButton("Close Program");
private JButton getCloseButton(){
return closeButton;
}
private JButton getOpenReportSelection(){
return openReportSelection;
}
public MainGUI(){
mainInterface();
}
private void mainInterface(){
setTitle("Program Information Application");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel centerPanel = new JPanel(new FlowLayout());
centerPanel.add(openReportSelection);
openReportSelection.addActionListener(new ActionListener(){
#Override
public void actionPerformed(ActionEvent e){
JFrame reports = new JFrame();
new ReportGUI();
}
});
centerPanel.add(closeButton);
getCloseButton().addActionListener(new Listener());
add(centerPanel, BorderLayout.CENTER);
setSize(700,200);
setVisible(true);
}
}
You can use a BoxLayout as it aligns all elements either horizontally or vertically. Simply set BoxLayout's axis to BoxLayout.Y_AXIS.
Example:
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.BoxLayout;
import javax.swing.JButton;
public class BoxLayoutExample extends JFrame {
private static final long serialVersionUID = 1L;
private JPanel contentPane;
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
BoxLayoutExample frame = new BoxLayoutExample();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public BoxLayoutExample() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 180, 150);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(new BoxLayout(contentPane, BoxLayout.Y_AXIS));
JButton btnOpenReportViewer = new JButton("Open Report Viewer");
contentPane.add(btnOpenReportViewer);
JButton btnCloseProgram = new JButton("Close Program");
contentPane.add(btnCloseProgram);
}
}
If you want to control the size so that they are similar to each other, you can use a grid layout by setting the JFrame's content pane to a GridLayout:
contentPane.setLayout(new GridLayout(0, 1, 0, 0)); // the value of 1 here means 1 column
Don't put the JButtons in a container that uses FlowLayout but rather one that uses another layout that allows stacking of components. A GridLayout comes to mind if the buttons are to be the same size, or if they need to be different sizes, a BoxLayout.
Check out the Layout Manager Tutorial.
You could try using a BoxLayout instead of a FlowLayout. In that case, you could have:
JPanel centerPanel = new JPanel(new BoxLayout());
centerPanel.setLayout(new BoxLayout(centerPanel, BoxLayout.Y_AXIS)); // Y_AXIS will cause the components to be added vertically
centerPanel.add(openReportSelection);
centerPanel.add(closeButton);
centerPanel.setMaximumSize(new Dimension(100, 60)); // Set the maximum horizontal and vertical distances used, as BoxLayouts expand to fill the provided area
Or as Hovercraft said, you could use a GridLayout, in which case you would specify it as follows:
JPanel centerPanel = new JPanel(new GridLayout(1,0); // The "0" parameter specifies as many rows as needed, but only one column
centerPanel.add(openReportSelection);
centerPanel.add(closeButton);
centerPanel.setMaximumSize(new Dimension(100, 60)); // GridLayouts will also expand to fill the entire area, so you'll probably want some size parameters.
You could also see this link for more on BoxLayouts, or this link for more on GridLayouts.
What I am trying to achieve is
Create a custom component (mypanel) that extends JPanel with JLabels and JButtons in it arranged via GridBagLayout.
Have a JFrame that would display multiple mypanel in a vertical stack and have its height change accordingly, depending on the number of mypanels added to it (width of the JFrame = width of mypanel).
When the JFrame's height becomes greater than the screen height, have a vertical scrollbar appear for scrolling
I have created mypanel successfully but having lot of trouble with the adding to the JFrame and setting its size, scrollbars part.
this is the code for my jframe
this.window = new JFrame("ADesktop Notifications");
this.window_panel = new JPanel();
this.window_panel_scroll = new JScrollPane(this.window_panel);
this.window.setBounds(this.top_left_x,this.top_left_y, this.width, this.height);
this.window_panel.setLayout(new FlowLayout());
this.window_panel.setAutoscrolls(true);
this.window.add(this.window_panel);
Try this example out (for dynamic expanding JFrame).
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class DynaFrame extends JFrame{
private JPanel basePnl = new JPanel();
public DynaFrame(){
this.setTitle("Dynamic panel addition");
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//this.setSize(600, 700);
this.add(getMainPanel());
this.setLocationRelativeTo(null);
this.pack();
this.setVisible(true);
}
public static void main(String[] args){
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new DynaFrame();
}
});
}
public JPanel getMainPanel(){
basePnl.setLayout(new BoxLayout(basePnl, BoxLayout.Y_AXIS));
basePnl.add(getRowPanel());
return basePnl;
}
public JPanel getRowPanel(){
JPanel pnl = new JPanel();
GridLayout gLayout = new GridLayout();
gLayout.setColumns(4);
gLayout.setRows(1);
pnl.setLayout(gLayout);
pnl.add(new JLabel("Filetype"));
pnl.add(new JTextField());
pnl.add(new JButton("Browse"));
JButton addBtn = new JButton("Add");
addBtn.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
basePnl.add(getRowPanel());
DynaFrame.this.pack();
}
});
pnl.add(addBtn);
return pnl;
}
}
I am new to Java and mostly CardLayout. I want to simply switch "windows" represented by JPanels. I read somewhere that job for CardLayout. But my problem is, when add chatPanel to mainPanel (this is the CardLayout one), it shifts the content of connectPanel several pixels to the top, away from its centered position. Is I skip in my code createChatPanel(), its where it should be.
I have this code:
package App;
import java.awt.CardLayout;
import java.awt.Dimension;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
import Validators.*;
public class GUI {
private JFrame mainFrame = null;
private JPanel mainPanel = null;
private CardLayout cl = new CardLayout();
public GUI(){
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
}
catch (UnsupportedLookAndFeelException e) {
}
catch (ClassNotFoundException e) {
}
catch (InstantiationException e) {
}
catch (IllegalAccessException e) {
}
mainFrame = new JFrame("MainChat");
mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
mainFrame.setSize(640,480);
mainFrame.setLocationRelativeTo(null);
mainFrame.setResizable(false);
mainFrame.setLayout(new GridBagLayout());
JMenuBar menuBar = new JMenuBar();
JMenu menuFile = new JMenu("Soubor");
JMenu menuHelp = new JMenu("Nápověda");
menuBar.add(menuFile);
menuBar.add(menuHelp);
menuFile.add(new JMenuItem("Nové Připojení"));
menuFile.add(new JSeparator());
menuFile.add(new JMenuItem("Konec"));
menuHelp.add(new JMenuItem("O programu"));
mainFrame.setJMenuBar(menuBar);
createMainPanel();
createConnectPanel();
createChatPanel();
mainFrame.setVisible(true);
}
public void createMainPanel() {
mainPanel = new JPanel(cl);
mainFrame.add(mainPanel);
}
public void createConnectPanel() {
JPanel connectPanel = new JPanel();
mainPanel.add(connectPanel,"connectPanel");
JTextField ip = new JTextField();
ip.setDocument(new JTextFieldLimit(15));
ip.setColumns(11);
JLabel iplabel = new JLabel("IP:");
connectPanel.add(iplabel);
connectPanel.add(ip);
JButton connect = new JButton("Connect");
connect.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
cl.show(mainPanel,"chatPanel");
}
});
connectPanel.add(connect);
}
public void createChatPanel(){
JPanel chatPanel = new JPanel();
mainPanel.add(chatPanel,"chatPanel");
JTextArea chatbox = new JTextArea();
chatbox.setPreferredSize(new Dimension(200,200));
chatPanel.add(chatbox);
}
}
Please, what I messed up? Thanks.
Since you are adding two JPanels to your main JPanel,
these two panels both need to fit within the main panel.
If one of the inner panels is much larger than the other one,
the main panel will adjust to fit the larger one.
E.g. commenting this line:
chatbox.setPreferredSize(new Dimension(200,200));
would cause your text field to stay put. This is because the
chatbox would not cause the container to resize.
Also note that the main panel is not initially the same size as your
main frame, since you have not set the size of the main panel.
If you would set the size of the connectPanel to the same size
as your main frame, the connectPanel would not
be automatically resized when adding the chatPanel (as a
consequence of the mainPanel being resized)
So what you could do is add the middle line in:
JPanel connectPanel = new JPanel();
connectPanel.setSize(640, 480);
mainPanel.add(connectPanel, "connectPanel");
, which probably would solve your problem.
Although this would work, I definitely recommend using
MIG Layout for
all your GUI designing. It will save you plenty of time if
you take an hour to learn it. It will also save you from
having to set sizes manually (and thereby saving you from
having to rewrite half your GUI code with every design change).
If you want a JPanel centered in another, place your connectPanel in another JPanel that acts as a dumb container, and have this container use GridBagLayout. Then if you add the connectPanel to the container without any GridBagConstraints, it will be added to the default position for GridBagLayout which is centered. You can then add this container JPanel to your mainPanel using the same constant that you would have used for your connectPanel.
I would tend to let the layouts determine the size of components and avoid using setSize and even setPreferredSize, and would definitely call pack() on my JFrame prior to setting it visible. You definitely don't want to set the size or preferredSize of your JTextField, but rather set its columns and rows and place it in a JScrollPane, and then add that JScrollPane to the view.
Edit:
Here's an example that shows placement of something like your connect panel at the top, middle and bottom of a small gui. Just press the "Next" button to see what I mean:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
#SuppressWarnings("serial")
public class GUI2 extends JPanel {
public static final String CONNECT_NORTH = "connect north";
public static final String CONNECT_CENTER = "connect center";
private static final String CONNECT_SOUTH = "connect south";
private static final String CHAT_PANEL = "chat panel";
private CardLayout cardlayout = new CardLayout();
public GUI2() {
setLayout(cardlayout);
add(createConnectPanel(BorderLayout.NORTH), CONNECT_NORTH);
add(createConnectPanel(BorderLayout.CENTER), CONNECT_CENTER);
add(createConnectPanel(BorderLayout.SOUTH), CONNECT_SOUTH);
add(createChatPanel(), CHAT_PANEL);
}
public void nextPanel() {
cardlayout.next(this);
}
private JPanel createConnectPanel(String borderlayoutLocation) {
JPanel innerPanel = new JPanel();
innerPanel.add(new JLabel("IP:"));
innerPanel.add(Box.createHorizontalStrut(5));
innerPanel.add(new JTextField(11));
innerPanel.add(Box.createHorizontalStrut(5));
innerPanel.add(new JButton(new AbstractAction("Next") {
#Override
public void actionPerformed(ActionEvent arg0) {
GUI2.this.nextPanel();
}
}));
JPanel innerPanel2 = new JPanel(new GridBagLayout());
innerPanel2.add(innerPanel);
JPanel connectPanel = new JPanel(new BorderLayout());
connectPanel.add(innerPanel2, borderlayoutLocation);
return connectPanel;
}
private JPanel createChatPanel() {
JPanel chatPanel = new JPanel(new BorderLayout(5, 5));
chatPanel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
chatPanel.add(new JScrollPane(new JTextArea(15, 30)), BorderLayout.CENTER);
chatPanel.add(new JTextField(), BorderLayout.SOUTH);
return chatPanel;
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createGui();
}
});
}
private static void createGui() {
JFrame frame = new JFrame("App");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new GUI2());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}