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POUnable to add object to ArrayList throught input by jtextField()
 

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    <p>When you press the <code>JButton</code> <kbd>Ny</kbd> the user input is supposed to be added as an object(class <code>Deltagare</code>) in an <code>ArrayList</code>, and when the user later press the <code>JButton</code> <kbd>Visa</kbd>, it should show up in the <code>JTextArea</code>.</p> <p>The problem is that the textArea only displays an empty Arraylist, somehow the input isn't added to the Arraylist.</p> <pre><code>import java.awt.*; import java.awt.event.*; import java.util.ArrayList; import javax.swing.*; class Tävling extends JFrame { public static ArrayList&lt;Deltagare&gt; list = new ArrayList&lt;Deltagare&gt;(); JTextArea text = new JTextArea(); JRadioButton rb1 = new JRadioButton("Startnr", true); JRadioButton rb2 = new JRadioButton("Namn", false); JRadioButton rb3 = new JRadioButton("Ålder", false); JRadioButton rb4 = new JRadioButton("Tid", false); Tävling() { super ("DSV Kista Marathon"); setLayout(new BorderLayout()); //NORTH JPanel north = new JPanel(); north.add(new JLabel("DSV Kista Marathon")); add(north, BorderLayout.NORTH); //CENTER add(new JScrollPane(text), BorderLayout.CENTER); text.setEditable(false); //EAST JPanel east = new JPanel(); east.setLayout(new BoxLayout(east, BoxLayout.Y_AXIS)); east.add(new JLabel("Sortering")); east.add(rb1); east.add(rb2); east.add(rb3); east.add(rb4); ButtonGroup group = new ButtonGroup(); group.add(rb1); group.add(rb2); group.add(rb3); group.add(rb4); add(east, BorderLayout.EAST); //SOUTH JPanel south = new JPanel(); JButton b1 = new JButton("Ny"); b1.addActionListener(new B1()); south.add(b1); JButton b2 = new JButton("Visa"); b2.addActionListener(new B2()); south.add(b2); JButton b3 = new JButton("Tid"); b3.addActionListener(new B3()); south.add(b3); add(south, BorderLayout.SOUTH); //Set setLocation(500,200); setDefaultCloseOperation(EXIT_ON_CLOSE); setSize(300,350); setVisible(true); } //Metod för att skapa startnr public int getStartnr() { int startnr = list.size()+1; return startnr; } public static void main(String[] args) { new Tävling(); } //Huvudklass slut ------------------------------------------------------ //b1 - Ny class B1 implements ActionListener { public void actionPerformed(ActionEvent ave) { new F1(); } } //b2 - Visa class B2 implements ActionListener { public void actionPerformed(ActionEvent ave) { if (rb1.isSelected()) text.append(list.toString() + "\n"); else if (rb2.isSelected()) text.setText("Namn"); else if (rb3.isSelected()) text.setText("Ålder"); else if (rb4.isSelected()) text.setText("Tid"); } } //b3 - Tid class B3 implements ActionListener { public void actionPerformed(ActionEvent ave) { new F2(); } } //JOptionPane - Ny (Deltagare) class F1 implements ActionListener { JTextField nfield = new JTextField(12); JTextField cfield = new JTextField(12); JTextField afield = new JTextField(3); F1() { JPanel form = new JPanel(); form.add(new JLabel("Startnr "+ getStartnr())); form.setLayout(new BoxLayout(form, BoxLayout.Y_AXIS)); JPanel r1 = new JPanel(); r1.add(new JLabel ("Namn:")); r1.add(nfield); form.add(r1); nfield.addActionListener(this); JPanel r2 = new JPanel(); r2.add(new JLabel ("Land:")); r2.add(cfield); form.add(r2); cfield.addActionListener(this); JPanel r3 = new JPanel(); r3.add(new JLabel ("Ålder:")); r3.add(afield); form.add(r3); afield.addActionListener(this); JOptionPane.showConfirmDialog(null, form, "Ny Tävlande" , JOptionPane.OK_CANCEL_OPTION); } public void actionPerformed(ActionEvent ave) { String name = nfield.getText(); String country = cfield.getText(); int age = Integer.parseInt(afield.getText()); int startnr = getStartnr(); list.add(new Deltagare(name, country, age, startnr)); } } //JOptionPane - Tid (Registrera ny) class F2 { JTextField field1 = new JTextField(6); JTextField field2 = new JTextField(6); F2() { JPanel form = new JPanel(); form.setLayout(new BoxLayout(form, BoxLayout.Y_AXIS)); JPanel r1 = new JPanel(); r1.add(new JLabel ("Startnr:")); r1.add(field1); form.add(r1); JPanel r2 = new JPanel(); r2.add(new JLabel ("Tid:")); r2.add(field2); form.add(r2); JOptionPane.showConfirmDialog(null, form, "Registrera Tid" , JOptionPane.OK_CANCEL_OPTION); } } } </code></pre> <p>And the Class Deltagare:</p> <pre><code>public class Deltagare { public String name,country; public int age,startnr; public Deltagare(String n, String c, int a, int b) { this.name = "n"; this.country = "c"; this.age = a; this.startnr = b; } public void setStartnr(int b) { startnr = b; } public int getStartnr() { return startnr; } public String getName() { return name; } public String getCountry() { return country; } public int getAge() { return age; } public String toString() { return startnr + "" + name + " " + country + " " + age; } } </code></pre>
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