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Use multiple layout manager in JAVA

I want to place the button below the "898 Food Restaurant" Jlabel. The setLocation() for button not working.
public class MainMenu extends JPanel{
JLabel picLabel,title;
JButton button;
public MainMenu() throws IOException
{
JPanel panel = new JPanel(new BorderLayout());
BufferedImage myPicture = ImageIO.read(new File("C:\\Users\\seng\\workspace\\FoodOrderingSystem\\ramen-noodles.png"));
Image scaled = myPicture.getScaledInstance(170,170,Image.SCALE_SMOOTH);
picLabel = new JLabel(new ImageIcon(scaled));
title = new JLabel("898 Food Restaurant");
title.setFont(new Font("Serif",Font.ITALIC+Font.BOLD,18));
title.setForeground(Color.BLUE);
button = new JButton("Order Food Now >>");
button.setLocation(40,380);
button.setSize(40,80);
panel.add(picLabel,BorderLayout.CENTER);
panel.add(title,BorderLayout.SOUTH);
JPanel buttonPanel = new JPanel();
buttonPanel.add(button);
add(buttonPanel);
add(panel);
button.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
OrderMainPage order = new OrderMainPage();
}
});
}
public static void main(String args[]) throws IOException
{
MainMenu main = new MainMenu();
JFrame frame = new JFrame();
frame.setTitle("898 Food Ordering System");
frame.add(main);
// frame.setSize(120,130);
frame.pack(); // size
frame.setLocationRelativeTo(null); // place frame in center
frame.setVisible(true);
}
}

Each JComponent such as JPanel can only have one layout manager at a time. But since JComponents can be nested you can have different layout managers in your JFrame. Usually that is how you create complex layouts.
Now for your question about button placement. The setLocation won't do anything since your button is in JPanel and it by default uses FlowLayout that ignores location attribute. First step is to set buttonPanel layout to null. But that still might not be enough since the buttonPanel is positioned by another flow layout that will set it's bounds not within the location coordinates of the nested button.
You can always see your JPanel bounds by setting it's background to a different color.
My advice to always try to position your components using layout managers and avoid absolute positioning.

you can use BoxedLayout in place of FrameLayout :
import java.awt.*;
import javax.swing.*;
import java.io.*;
import java.awt.image.*;
import javax.imageio.*;
class MainMenu extends Frame {
JLabel picLabel,title;
JButton button;
public MainMenu () {
JPanel panel = new JPanel(new BorderLayout());
try{
BufferedImage myPicture = ImageIO.read(new File("C:\\Users\\seng\\workspace\\FoodOrderingSystem\\ramen-noodles.png"));
Image scaled = myPicture.getScaledInstance(170,170,Image.SCALE_SMOOTH);
picLabel = new JLabel(new ImageIcon(scaled));}catch(Exception e){}
title = new JLabel("898 Food Restaurant");
title.setFont(new Font("Serif",Font.ITALIC+Font.BOLD,18));
title.setForeground(Color.BLUE);
button = new JButton("Order Food Now >>");
panel.add(picLabel,BorderLayout.CENTER);
panel.add(title,BorderLayout.SOUTH);
JPanel buttonPanel = new JPanel();
buttonPanel.add(button);
add(panel);
add(buttonPanel);
setLayout (new BoxLayout (this, BoxLayout.Y_AXIS));
setSize(400,400);
setVisible(true);
}
public static void main(String args[]){
MainMenu main = new MainMenu();
}
}

JFrame strange white stripe on top of background image

I have a strange white stripe (see below) appearing on top of my background image. The code is quite simple. How to get rid of the white stripe?
//Graphics side of the game
public class GUI extends JFrame {
private final int larghezza = 1280;
private final int altezza = 720;
private final String name = "Sette e Mezzo";
private final ImageIcon backgroundImage;
private JLabel bgImageLabel;
private JPanel backgroundPanel, borderLayoutPanel, topGridLayout, botGridLayout;
public GUI () {
backgroundImage = new ImageIcon ("assets/background.png");
bgImageLabel = new JLabel (backgroundImage);
//Panels
borderLayoutPanel = new JPanel (new BorderLayout ());
topGridLayout = new JPanel (new GridLayout (1, 3));
botGridLayout = new JPanel (new GridLayout (1, 3));
backgroundPanel = new JPanel ();
backgroundPanel.add (bgImageLabel);
//Frame
this.setName (name);
this.setPreferredSize (new Dimension(larghezza, altezza));
this.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
//Adding to frame and panels
borderLayoutPanel.add (topGridLayout, BorderLayout.NORTH);
borderLayoutPanel.add (botGridLayout, BorderLayout.SOUTH);
this.add (borderLayoutPanel);
this.add (backgroundPanel);
this.pack ();
this.setLocationRelativeTo (null);
this.setVisible (true);
}
}

Don't use setPreferredSize() when you really mean to override getPreferredSize(). In this case, the specified Dimension probably doesn't quite match the size of "assets/background.png". This allows some portion of another panel to show, perhaps backgroundPanel.
In the example below,
The default layout of JPanel is FlowLayout, which has a "default 5-unit horizontal and vertical gap." A touch of Color.blue makes the gap stand out; resize the enclosing frame to see the behavior.
As the default layout of JFrame is BorderLayout, you may not need borderLayoutPanel at all.
Because the two GridLayout panels have no content, they remain invisible. Add content to each or override getPreferredSize() in each to see the effect.
Construct and manipulate Swing GUI objects only on the event dispatch thread.
import java.awt.*;
import java.net.URL;
import javax.swing.*;
public class GUI {
private static final String TITLE = "Title";
private static ImageIcon IMAGE_ICON;
private void display() {
//Panels
JPanel topGridLayout = new JPanel(new GridLayout(1, 3));
JPanel botGridLayout = new JPanel(new GridLayout(1, 3));
JPanel backgroundPanel = new JPanel();
backgroundPanel.setBackground(Color.blue);
backgroundPanel.add(new JLabel(IMAGE_ICON));
//Frame
JFrame f = new JFrame(TITLE);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Add components
f.add(topGridLayout, BorderLayout.NORTH);
f.add(backgroundPanel);
f.add(botGridLayout, BorderLayout.SOUTH);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
public static void main(String[] args) throws Exception {
IMAGE_ICON = new ImageIcon(new URL("http://i.imgur.com/mowekvC.jpg"));
EventQueue.invokeLater(new GUI()::display);
}
}

How can I properly adjust the size and location of a button in JFrame?

I am attempting to make a PC Application using Java and JFrame. I'm trying to format 2 transparent buttons, each sized half of the full screen shown (vertically). The top half of the screen will hold to option to debate someone and the bottom half of the screen will hold the option to spectate a debate if clicked on. Here is what I have so far:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
class BackgroundImageJFrame extends JFrame {
JButton b1;
JButton b2;
JPanel j1;
JPanel j2;
public BackgroundImageJFrame() {
setTitle("Background Color for JFrame");
setSize(340,563);
setLocationRelativeTo(null);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setVisible(true);
setLayout(null);
/*
One way
-----------------
setLayout(new BorderLayout());
JLabel background=new JLabel(new ImageIcon("C:\\Users\\Computer\\Downloads\\colorful design.png"));
add(background);
background.setLayout(new FlowLayout());
l1=new JLabel("Here is a button");
b1=new JButton("I am a button");
background.add(l1);
background.add(b1);
*/
// Another way
setLayout(new BorderLayout());
setContentPane(new JLabel(new ImageIcon("C:\\Users\\MLH-User\\Downloads\\Front.jpg")));
setLayout(new FlowLayout());
j1 = new JPanel();
j1.setLayout(null);
b1 = new JButton("Spectate");
//b1.setBounds(0,0,50,50);
b1.setOpaque(false);
b1.setContentAreaFilled(false);
b1.setBorderPainted(false);
j1.add(b1);
b2 = new JButton("Debate");
b2.setLocation(0,0);
b2.setOpaque(false);
b2.setContentAreaFilled(false);
b2.setBorderPainted(false);
j1.add(b2);
add(j1);
// Just for refresh :) Not optional!
setSize(339,562);
setSize(340,563);
}
public static void main(String args[]) {
new BackgroundImageJFrame();
}
}
This is some stuff I experimented with so far, can anyone help me out about where I went wrong?

You should use a layout manager. Here is an example with GridLayout:
public class Example extends JFrame {
private static final int SIZE = 300;
public Example() {
setLayout(new GridLayout(2, 1, 0, 5));
getContentPane().setBackground(Color.WHITE);
JButton debate = new JButton("DEBATE") {
public Dimension getPreferredSize() {
return new Dimension(SIZE, SIZE);
}
};
Font font = debate.getFont().deriveFont(30f);
debate.setFont(font);
// debate.setBorderPainted(false);
debate.setBackground(Color.BLUE.brighter());
debate.setForeground(Color.WHITE);
JButton spectate = new JButton("SPECTATE") {
public Dimension getPreferredSize() {
return new Dimension(SIZE, SIZE);
}
};
spectate.setFont(font);
// spectate.setBorderPainted(false);
spectate.setBackground(Color.RED.brighter());
spectate.setForeground(Color.WHITE);
add(debate);
add(spectate);
setDefaultCloseOperation(EXIT_ON_CLOSE);
pack();
setVisible(true);
}
public static void main(final String[] args) {
SwingUtilities.invokeLater(() -> new Example());
}
}
Notes:
You have to realize that screen sizes vary. Setting SIZE to 300 was an arbitrary choice for presentation, screens might not have the required size. You can also set the insets or an empty border instead of specifying the size of the component directly.
You can consider creating a class for these buttons if you have more of them.

This is an example of setting the sizes. I don't know about the location part though.
JFrame frame = new JFrame("test");
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
JPanel panel = new JPanel(new GridLayout(4,4,4,4));
for(int i=0 ; i<16 ; i++){
JButton btn = new JButton(String.valueOf(i));
btn.setPreferredSize(new Dimension(40, 40));
panel.add(btn);
}
frame.setContentPane(panel);
frame.pack();
frame.setVisible(true);

Remove huge gaps between check boxes on panel

Its pretty basic UI, but I cannot setup the JCheckBox buttons so that they are placed immediately after one another (vertically) without any spacing. How would I reduce the spacing seen below?
JPanel debugDrawPanel = new JPanel(new GridLayout(0,1));
JPanel eastPanel = new JPanel(new GridLayout(1,0));
JTabbedPane tab = new JTabbedPane();
click = new ClickPanel(this);
setSettings(new Settings());
for (Setting setting: getSettings().getAll()){
JCheckBox checkBox = new JCheckBox(setting.name);
checkBox.setName(setting.name);
checkBox.addItemListener(new CheckBoxItemListener(this));
debugDrawPanel.add(checkBox);
}
tab.addTab("Object Parameters", click);
tab.addTab("Debug Draw", debugDrawPanel);

It appears that the minimum vertical size is being set by the content of another tab. One way to get around that is to put the GridLayout in the PAGE_START of a BorderLayout before putting the panel with border layout into the tabbed pane.
The panel with GridLayout has an orange BG.
The panel with BorderLayout has a yellow BG.
import java.awt.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
import javax.swing.border.EmptyBorder;
public class TopAlignedComponents {
private JComponent ui = null;
TopAlignedComponents() {
initUI();
}
public void initUI() {
if (ui!=null) return;
ui = new JPanel(new BorderLayout(4,4));
ui.setBorder(new EmptyBorder(4,4,4,4));
JTabbedPane tb = new JTabbedPane();
ui.add(tb);
Image spacer = new BufferedImage(300, 100, BufferedImage.TYPE_INT_RGB);
tb.addTab("Spacer", new JLabel(new ImageIcon(spacer)));
String[] labels = {"Shapes", "Joints", "AABBs"};
JPanel checkPanel = new JPanel(new GridLayout(0, 1, 4, 4));
checkPanel.setBackground(Color.ORANGE);
for (String label : labels) {
checkPanel.add(new JCheckBox(label));
}
JPanel checkConstrain = new JPanel(new BorderLayout());
checkConstrain.setBackground(Color.YELLOW);
checkConstrain.add(checkPanel, BorderLayout.PAGE_START);
tb.addTab("Check", checkConstrain);
}
public JComponent getUI() {
return ui;
}
public static void main(String[] args) {
Runnable r = new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception useDefault) {
}
TopAlignedComponents o = new TopAlignedComponents();
JFrame f = new JFrame("Top Aligned Components");
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
f.setLocationByPlatform(true);
f.setContentPane(o.getUI());
f.pack();
f.setMinimumSize(f.getSize());
f.setVisible(true);
}
};
SwingUtilities.invokeLater(r);
}
}

If i remember correctly, its because of your layout!
GridLayout divides your windowsize into equal parts, so i think you should either unset your windows size and use pack() or you could switch to a different layout.
( I assume your window's size is or minimum-size is set somewhere )

Java CardLayout JPanel moves up, when second JPanel added

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);
}
}