So I'm getting the error: "CANNOT REFER TO A NON-FINAL VARIABLE ROLE INSIDE AN INNERCLASS DEFINED IN A DIFFERENT METHOD". I want to be able to set the string roletype to whatever get's selected in that Dropdown. How can I do this if not in the way I'm trying below, or am I simply making some stupid error in the code I'm trying?
Thanks, Ravin
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import javax.swing.*;
import javax.swing.event.*;
public class Funclass extends JFrame {
FlowLayout layout = new FlowLayout();
String[] skillz = {"Analytical", "Numerical", "Leadership",
"Communication", "Organisation", "Interpersonal"};
String[] rolez = {"Developer", "Sales", "Marketing"};
String[] Industries = {"Consulting", "Tech"};
String R1, R2, R3, R4, roletype;
public Funclass() {
super("Input Interface");
setLayout(layout);
JTextField Company = new JTextField("Company Name");
JComboBox TYPE = new JComboBox(Industries);
JList skills = new JList(skillz);
JComboBox role = new JComboBox(rolez);
skills.setSelectionMode(ListSelectionModel.MULTIPLE_INTERVAL_SELECTION);
add(TYPE);
add(skills);
add(role);
add(Company);
ROLE.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent event) {
if (event.getStateChange() == ItemEvent.SELECTED) {
roletype = rolez[role.getSelectedIndex()];
}
}
});
}
}
您需要将role
变量声明为final
以便内部类( ItemListener
)可以访问它,如下所示:
final JComboBox role = new JComboBox(rolez);
import java.awt.event.*;
import javax.swing.*;
public class Funclass extends JFrame {
private static final long serialVersionUID = 1L;
private String[] rolez = {"Developer", "Sales", "Marketing"};
private String roletype;
private JComboBox role;
public Funclass() {
role = new JComboBox(rolez);
role.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent event) {
if (event.getStateChange() == ItemEvent.SELECTED) {
roletype = role.getSelectedItem().toString();
}
}
});
}
}
To access variables in the outer class from an inner class, they must be declared final
. So in this case, role
must be final
.
EDIT: roletype
does not need to be declared final
even though it's accessed in the innerclass because it is a class variable, not a method variable.
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