Reputation: 71
I am trying to get this code to work, such that I have a cardlayout container and each panel be defined in its own class and actual file. This code is not 100% my own and is a modified version of my previous stuff by another Stack overflow user. It is more or less what I need, but I need it such that it isn't automated and I can write 15 different panels with decisions made inside each one. The Main and Arrow class was modified by said user, and Imagepanel is my attempt to write a class that will be accepted by the working part of the code. The issue is the Imagepanel I insert into the container will register as existing, but nothing shows up on the panel, it's blank. The commented out portion in ImagePanel is my code that I set on the back burner in favor of the established stuff previously used in the Arrow class.
Here is the Main class
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.*;
import javax.swing.*;
public class Main extends JPanel {
private Arrow arrow = new Arrow(); //creates a new Arrow object
public Main() {
JPanel btnPanel = new JPanel();
btnPanel.add(new JButton(new NextAction("Next")));
setLayout(new BorderLayout());
add(arrow, BorderLayout.NORTH);
add(btnPanel, BorderLayout.PAGE_END);
}
private class NextAction extends AbstractAction {
public NextAction(String name) {
super(name);
}
@Override
public void actionPerformed(ActionEvent e) {
arrow.next(); // *** call arrow's public next method that you created
// no need to make a new CardLayout instance
}
}
private static void createAndShowGui() {
Main mainPanel = new Main();
JFrame frame = new JFrame("Iowa Budget Simulation");
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(() -> createAndShowGui());
}
}
Here is the Arrow class where the container is created
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridBagLayout;
import javax.swing.*;
class Arrow extends JPanel {
private static final long serialVersionUID = 1L;
private CardLayout cardLayout = new CardLayout(); // make me a field
private JPanel cardHolder = new JPanel(cardLayout); //creates a master JPanel
public Arrow() {
for (int i = 0; i < 5; i++) {
cardHolder.add(createCard(i), "card " + i);
}
ImagePanel pear = new ImagePanel();
cardHolder.add(pear, "Pear");
setLayout(new BorderLayout());
add(cardHolder, BorderLayout.NORTH);
}
// public method that other objects can call
public void next() {
cardLayout.next(cardHolder); // call next on the correct object
}
// simply creates a "pretty" new JPanel
private JComponent createCard(int i) {
JLabel label = new JLabel("Card " + i);
label.setFont(label.getFont().deriveFont(Font.BOLD, 50f));
float h = (float)Math.random();
Color c = Color.getHSBColor(h, 1f, 1f);
label.setForeground(c.darker());
JPanel panel = new JPanel(new GridBagLayout());
panel.add(label);
panel.setBorder(BorderFactory.createLineBorder(c.darker(), 20));
panel.setBackground(c.brighter().brighter());
panel.setPreferredSize(new Dimension(400, 300));
return panel;
}
Here is ImagePanel, my attempt at a 3rd, individual panel/class
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridBagLayout;
import javax.swing.*;
class ImagePanel extends JPanel {
private static final long serialVersionUID = 1L;
private String imgString;
private JLabel imgLabel;
public JComponent ImagePanel() {
/*
setName("Pear");
JLabel john = new JLabel("Pear");
float h = (float)Math.random();
Color c = Color.getHSBColor(h, 1f, 1f);
john.setForeground(c.darker());
JPanel panel = new JPanel(new GridBagLayout());
panel.add(john);
panel.setBorder(BorderFactory.createLineBorder(c.darker(), 20));
panel.setBackground(c.brighter().brighter());
// Ensure size is correct even before any image is loaded.
setPreferredSize(new Dimension(400, 300));
return panel;
*/
JLabel label = new JLabel("Pear");
label.setFont(label.getFont().deriveFont(Font.BOLD, 50f));
float h = (float)Math.random();
Color c = Color.getHSBColor(h, 1f, 1f);
label.setForeground(c.darker());
JPanel panel = new JPanel(new GridBagLayout());
panel.add(label);
panel.setBorder(BorderFactory.createLineBorder(c.darker(), 20));
panel.setBackground(c.brighter().brighter());
panel.setPreferredSize(new Dimension(400, 300));
return panel;
}
There is no error to post, it simply displays a blank panel. Thank you for any assistance I might receive, and I apologize in advance as I am learning Java Swing GUI through YouTube and stack overflow.
Upvotes: 0
Views: 440
Reputation: 347214
public JComponent ImagePanel() {
isn't a constructor, it's a method, to make it work in your code you would have to change ImagePanel pear = new ImagePanel();
to JComponent pear = new ImagePanel().ImagePanel();
, but frankly that just doesn't make much sense.
Instead, change public JComponent ImagePanel() {
to public ImagePanel() {
, now it's the class's constructor
Next, change...
JPanel panel = new JPanel(new GridBagLayout());
panel.add(label);
panel.setBorder(BorderFactory.createLineBorder(c.darker(), 20));
panel.setBackground(c.brighter().brighter());
panel.setPreferredSize(new Dimension(400, 300));
return panel;
to
setLayout(new GridBagLayout());
add(label);
setBorder(BorderFactory.createLineBorder(c.darker(), 20));
setBackground(c.brighter().brighter());
//panel.setPreferredSize(new Dimension(400, 300));
//return panel;
Don't get me started on why setPreferredSize
is a bad idea
Now you can simply use
ImagePanel pear = new ImagePanel();
cardHolder.add(pear, "Pear");
Upvotes: 2