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JScroll Pane not visible in JPanel.[JAVA]

I am trying to add scrollbar to panel2 in the following code which contains an image in it. The problem is even though i add JScrollPane, i am getting no scrollbar in the output and it doesn't scroll either and i only see half of the image. Please help .
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.awt.image.*;
public class manga extends JPanel{
public static void main(String[] args) {
JFrame frame = new JFrame("Swing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel=new JPanel();
panel.setLayout(new BoxLayout(panel, BoxLayout.X_AXIS));
JPanel panel1=new JPanel();
JPanel panel2=new JPanel();
JButton button1=new JButton("PlAY");
button1.setBounds(100,300,70,30);
String path="01.jpg";
ImageIcon imageIcon = new ImageIcon(path);
JLabel label = new JLabel(imageIcon);
panel.setPreferredSize(new Dimension(1000,1000));
JScrollPane scroll = new JScrollPane(label);
scroll.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
panel2.add(scroll);
panel2.add(label);
panel1.setBackground(new Color(255,255,255));
panel2.setBackground(new Color(0,0,0));
panel1.add(button1);
panel.add(panel1);
panel.add(panel2);
frame.add(panel);
frame.setTitle("MANGA READER 0.1");
frame.setSize(1366,768);
frame.setVisible(true);
}
}
I think the error lies in the following code.
panel.setPreferredSize(new Dimension(1000,1000));
JScrollPane scroll = new JScrollPane(label);
scroll.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
panel2.add(scroll);
I am not sure.Please help

In Java Swing a component can have only one parent.
That means that by executing
panel2.add(scroll);
panel2.add(label);
you remove the label from the scroll pane.
Your don't need to add the label to the panel itself, so just drop that line and write only
panel2.add(scroll);

Resize JFrame to JPanels inside JLayeredPane

I'm working on a Swing GUI using the JLayeredPane. The JFrame has a JLayeredPane which contains two JPanels. Later I want to display some components in the JPanels, I cut this part of the code to make it shorter for you.
How do I resize the JFrame to the sizes of the JPanels? frame.pack() does not work and without the line setting the preferred size the GUI will show with minimal size.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridBagLayout;
import javax.swing.JFrame;
import javax.swing.JLayeredPane;
import javax.swing.JPanel;
public class TestGUI {
private JFrame frame;
private JLayeredPane layeredPane;
private JPanel panelBottom;
private JPanel panelTop;
private MainMenuBar menuBar;
public TestGUI() {
// panel bottom:
panelBottom = new JPanel();
panelBottom.setSize(1000, 500);
panelBottom.setBackground(new Color(0, 100, 0, 100));
panelBottom.setLayout(new GridBagLayout());
// panel top:
panelTop = new JPanel();
panelTop.setSize(950, 450);
panelTop.setBackground(new Color(0, 0, 100, 100));
panelTop.setLayout(new GridBagLayout());
// layered pane:
layeredPane = new JLayeredPane();
layeredPane.add(panelBottom, 1);
layeredPane.add(panelTop, 0);
// frame building:
frame = new JFrame();
menuBar = new MainMenuBar();
frame.setJMenuBar(menuBar);
frame.setLayout(new BorderLayout());
frame.setPreferredSize(new Dimension(1100, 600)); // <-- Without this the GUI will be very small
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(layeredPane, BorderLayout.CENTER);
frame.pack(); // <-- does not work!
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
new TestGUI();
}
}
EDIT: I could just change the preferred size line to fit the biggest JPanel, but i ask the question because I want the JFrame to resize depending on the size of the JPanels dynamically.

As suggested in How to Use Layered Panes: Laying Out Components in a Layered Pane, "Although a layered pane has no layout manager by default, you can still assign a layout manager to the layered pane." Use OverlayLayout, seen here, for overlapping panels.
Alternatively, use JInternalFrame, which does allow you to pack() the internal frames individually, as shown here and here.

Switch between different sized JPanels

To keep things short, I know how to switch between different JPanels using CardLayout and only using one JFrame but I want to know how, if it is possible, to have different sized JPanels occupying the JFrame. CardLayout uses the largest of the panels but I was wondering if there was any way to suppress that or override so that I could add different JPanels to a JFrame that were different sizes. Here is my code:
import java.awt.CardLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class View {
//Views
private JFrame frame;
private JPanel container;
private JPanel panel1;
private JPanel panel2;
private CardLayout layout;
private final int WIDTH = 1280;
private final int HEIGHT = 720;
public View(){
init();
frame = new JFrame();
frame.setResizable(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
frame.add(container);
frame.pack();
frame.setVisible(true);
}
private void init(){
JButton button = new JButton();
layout = new CardLayout();
container = new JPanel(layout);
panel1 = new JPanel();
panel2 = new JPanel();
panel1.setBackground(Color.WHITE);
panel1.setPreferredSize(new Dimension(500, 500));
panel1.add(button);
panel2.setBackground(Color.BLACK);
panel2.setPreferredSize(new Dimension(500, 500));
container.add(panel1, "panel1");
container.add(panel2, "panel2");
button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
layout.show(container, "panel2");
}
});
}
public static void main(String [] args){
View view = new View();
}
}
I put the JButton in the init method because I need it for future use and wanted to make sure now that it could be done.

For a quick solution try two separate JFrames, or resize the frame to the size of the panel on button press.

The only way it seems to work with the cardLayout is by setting the preferred size of the container panel after the button is clicked.
button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
layout.show(container, "panel2");
container.setPreferredSize(new Dimension(100, 100));
frame.pack();
}
});
It's not a very great solution but it's pretty simple.
If a login window is what you need I would definitely recommend using 2 frames, just seems more logical.

You can't use a CardLayout. So you need to manage the visible panel yourself.
The logic would be something like:
JPanel content = (JPanel)frame.getContentPane();
content.removeAll();
content.add( theOtherPanel );
frame.pack();
So the idea is you only have one panel added to the content pane at a time and you need to swap it by doing the remove and add before you pack the frame so the frame is displayed at the size of each panel.
The question is why do you want to do this? Users don't like to see the size of the frame continually changing.

Moving JButtons

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.

How to make this layout with Java swing?

I have the following layout:
The red, blue and green parts are JPanel. In the red part I have four JLabel. Now if I resize the JFrame, the title labels always stay in the center. But I would prefer if they are evenly distributed horizontaly in the red part. Which layout should I use for that?

Use a GridLayout(1, 0) for the top JPanel. The two numbers means 1 row and variable number of columns. If you are using JLabels, this will be sufficient, especially if you set the JLabels alignment constant to SwingConstants.CENTER. If you are using components that fill the grid slots, such as JButtons, then you may need to use other variants of the GridLayout constructor, such as GridLayout(1, 0, ?, 0) Where the ? is a number that tells the GridLayout how much horizontal separation there should be between slots.
The overall GUI would use a BorderLayout of course.
For more and better information on this, please check out Lesson: Laying Out Components Within a Container and A Visual Guide to Layout Managers
For example:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import javax.swing.*;
public class LayoutEg {
private static void createAndShowGui() {
String[] labelStrings = {"One", "Two", "Three", "Four"};
JPanel topPanel = new JPanel(new GridLayout(1, 0));
for (String labelString : labelStrings) {
// create labels and center the text
topPanel.add(new JLabel(labelString, SwingConstants.CENTER));
}
topPanel.setBackground(Color.red);
JPanel centerPanel = new JPanel();
centerPanel.setBackground(Color.blue);
// setting preferred size for demonstration purposes only
centerPanel.setPreferredSize(new Dimension(700, 400));
JPanel bottomPanel = new JPanel();
bottomPanel.setBackground(Color.green);
// main panel uses BorderLayout
JPanel mainPanel = new JPanel(new BorderLayout());
mainPanel.add(centerPanel, BorderLayout.CENTER);
mainPanel.add(topPanel, BorderLayout.PAGE_START);
mainPanel.add(bottomPanel, BorderLayout.PAGE_END);
JFrame frame = new JFrame("LayoutEg");
frame.setDefaultCloseOperation(JFrame.EXIT_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();
}
});
}
}

Use a BorderLayout for the frame's content pane, and use a GridLayout with 1 row and four columns for the title panel.
See http://docs.oracle.com/javase/tutorial/uiswing/layout/border.html and http://docs.oracle.com/javase/tutorial/uiswing/layout/grid.html for tutorials.
If you don't want the same width assigned to each label, but in fact want the same space between every label, you may also use a BoxLayout, and add a glue between each label (and between the border of the panel and the label:
p.setLayout(new BoxLayout(p, BoxLayout.X_AXIS));
p.add(Box.createHorizontalGlue());
p.add(new JLabel("Label"));
p.add(Box.createHorizontalGlue());
p.add(new JLabel("Long Label"));
p.add(Box.createHorizontalGlue());
p.add(new JLabel("Very long Label"));
p.add(Box.createHorizontalGlue());
p.add(new JLabel("Extremely long Label"));
p.add(Box.createHorizontalGlue());

Use a BorderLayout for the main frame and use the NORTH, CENTER and SOUTH places.
To create empty space like in the bottom panel, use Box.createVerticalStrut(size).
Use BoxLayout to place the labels packed in a row.
Finally use GridBagLayout to center a panel in another Panel.
Here is a short example:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridBagLayout;
import javax.swing.BorderFactory;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class Prototype extends JFrame {
public Prototype() {
JPanel labelPanel = new JPanel();
labelPanel.setLayout(new BoxLayout(labelPanel, BoxLayout.LINE_AXIS));
labelPanel.add(new JLabel("First"));
labelPanel.add(Box.createHorizontalStrut(10));
labelPanel.add(new JLabel("Second"));
labelPanel.setBorder(BorderFactory.createEmptyBorder(4, 4, 4, 4));
labelPanel.setOpaque(false);
JPanel bottomPanel = new JPanel();
bottomPanel.add(Box.createVerticalStrut(15));
bottomPanel.setBackground(Color.GREEN);
JPanel centerPanel = new JPanel();
centerPanel.add(Box.createRigidArea(new Dimension(200, 300)));
centerPanel.setBackground(Color.BLUE);
JPanel northPanel = new JPanel(new GridBagLayout());
northPanel.add(labelPanel);
northPanel.setBackground(Color.RED);
JPanel panel = new JPanel(new BorderLayout());
panel.add(northPanel, BorderLayout.NORTH);
panel.add(centerPanel, BorderLayout.CENTER);
panel.add(bottomPanel, BorderLayout.SOUTH);
add(panel);
pack();
setDefaultCloseOperation(EXIT_ON_CLOSE);
setVisible(true);
}
public static void main(String[] args) {
new Prototype();
}
}

Use a MigLayout.
No, seriously, I used to go crazy trying to get Java layouts working. Then I started maintaining some software that uses MigLayouts, and after a week or so I could do anything I wanted. There is an excellent cheat sheet that looks pretty intimidating, but it's incredibly helpful.
With a MigLayout, to have evenly spread labels in a JPanel you would:
// the "fillx" means that the layout will expand to take up all available horizontal space
JPanel panel = new JPanel(new Miglayout("fillx"));
// the "growx" means that the component will expand to take up all available horizontal space
add(new JLabel("Work items"), "growx");
add(new JLabel("Change set"), "growx");
add(new JLabel("Files"), "growx");
add(new JLabel("Source code"), "growx");

gridLayout, put the labels into the grid layout and set rows to 1 and columns to 4 (1 row for each Label)
http://www.javabeginner.com/java-swing/java-gridlayout-class-example

GridBagLayout is one approach. Set the weightx value to 1.0.

For labels to be distributed evenly horizantally - in the red panel - use BoxLayout with X_AXIS direction and put 'glue' between each label - More here -
http://docs.oracle.com/javase/tutorial/uiswing/layout/box.html