Compile Fehler beim Hinzufügen von Action zu Array erstellt GUI

Question

Ich hatte eine riesige Datei für diese GUI Erstellung und ich habe es verkürzt durch Verwendung von Arrays. Ich versuche, eine Action hinzufügen, aber wenn die Arrays hinzugefügt werden und ich erhalte die folgenden Fehler:

/tmp/jc_3531/GUI.java:60: addActionListener(java.awt.event.ActionListener) in javax.swing.AbstractButton cannot be applied to (GUI)
            nButtons[c].addActionListener( this );
                       ^
/tmp/jc_3531/GUI.java:69: cannot find symbol
symbol  : method addActionListener(GUI)
location: class javax.swing.JLabel
            labels[c].addActionListener( this );
                     ^
/tmp/jc_3531/GUI.java:78: addActionListener(java.awt.event.ActionListener) in javax.swing.JTextField cannot be applied to (GUI)
            fields[c].addActionListener( this );
                     ^
/tmp/jc_3531/GUI.java:90: addActionListener(java.awt.event.ActionListener) in javax.swing.AbstractButton cannot be applied to (GUI)
            sButtons[c].addActionListener( this );
                       ^
4 errors

Was mache ich falsch? Gibt es einen einfacheren Weg, sich selbst zu diagnostizieren (wie ein Editor mit integriertem Syntaxführer)?

Hier ist mein Code

// GUI with navigation amd file manipulation buttons
import javax.swing.*; // provides basic window features
import java.awt.event.*;
import java.awt.GridLayout;
import java.awt.BorderLayout;
import java.text.NumberFormat;

public class GUI extends JFrame 
{
    private Inventory inv;      
    private int currentDisplay = 0; 

    private JPanel nButtonJPanel;
    private String nNames[]={"Load","Add","Modify","Delete","Search","Save"};
    private JButton nButtons[];

    private JPanel labelJPanel;
    private String labeled[]={"Item ID","Name","Rating","# in Stock","Price","Inventory Value",
    "Restocking Fee (5%)","Inventory Value with Fee","Total Value with Fee (all DVD's)"};
    private JLabel labels[];

    private JPanel fieldJPanel;
    private String fieldsBlank[]={"","","","","","","","",""};
    private JTextField fields[];

    private JPanel sButtonJPanel;
    private String sNames[]={"First","Prev","","Next","Last"};
    private JButton sButtons[];

   // LabelFrame constructor adds JLabels to JFrame
   public GUI()
   {
      super( "Inventory Program v.5" );
      setLayout( new BorderLayout() ); // set frame layout

        // initialize values
        RatedDVD d1 = new RatedDVD(1, "One Flew Over The Cuckoo's Nest", 3, 9.99, "PG");
        RatedDVD d2 = new   RatedDVD(2, "The Matrix", 1, 13.01, "PG13");
        RatedDVD d3 = new   RatedDVD(3, "Se7en", 7, 11.11, "R");
        RatedDVD d4 = new   RatedDVD(4, "Oceans Eleven", 11, 9.02, "PG13");
        RatedDVD d5 = new   RatedDVD(5, "Hitch Hikers Guide to the Galaxy", 42, 10.00, "G");    
        RatedDVD d6 = new   RatedDVD(6, "The Invisible Man", 0, 4999.59, "G");  

        // create inv and enter values
        inv = new Inventory();
        inv.add(d1);
        inv.add(d2);
        inv.add(d3);
        inv.add(d4);
        inv.add(d5);
        inv.add(d6);

        inv.sort();

        //make nButtons
        nButtonJPanel.setLayout( new GridLayout( 1, nNames.length, 5, 5 ) );
        nButtons=new JButton[nNames.length];
        for(int c=0;c<nButtons.length;c++){
            nButtons[c]=new JButton(nNames[c]);
            nButtons[c].addActionListener( this );
            nButtonJPanel.add(nButtons[c]); }
        add( nButtonJPanel, BorderLayout.NORTH );

        //make labels
        labelJPanel.setLayout( new GridLayout( labeled.length, 1 ));
        labels=new JLabel[labeled.length];  
        for(int c=0;c<labels.length;c++){
            labels[c]=new JLabel(labeled[c]);
            labels[c].addActionListener( this );
            labelJPanel.add(labels[c]);}
        add( labelJPanel, BorderLayout.WEST );

        //make fields
        fieldJPanel.setLayout( new GridLayout( fieldsBlank.length, 1 ));
        fields=new JTextField[fieldsBlank.length];
        for(int c=0;c<fields.length;c++){
            fields[c]=new JTextField(fieldsBlank[c],28);
            fields[c].addActionListener( this );
            fields[c].setEditable(false);
            fieldJPanel.add(fields[c]); }
            populate(currentDisplay);
        add( fieldJPanel, BorderLayout.EAST );

        //make sButtons
        sButtonJPanel.setLayout( new GridLayout( 1, sNames.length, 5, 5 ) );
        sButtons=new JButton[sNames.length];    
        Icon dvd50 = new ImageIcon( getClass().getResource( "dvd50.jpg" ) );
        for(int c=0;c<sButtons.length;c++){
            sButtons[c]=new JButton(sNames[c]);
            sButtons[c].addActionListener( this );
            sButtonJPanel.add(sButtons[c]);}
        sButtons[2].setIcon( dvd50 );       
        add( sButtonJPanel, BorderLayout.SOUTH );
    }// end method

    public void populate(int currentDisplay)
    {
    NumberFormat nf = NumberFormat.getCurrencyInstance();
    fields[0].setText(String.valueOf(inv.get(currentDisplay).getItem()));
    fields[1].setText(inv.get(currentDisplay).getName());
    fields[2].setText(inv.get(currentDisplay).getRating());
    fields[3].setText(String.valueOf(inv.get(currentDisplay).getUnits()));
    fields[4].setText(String.valueOf(nf.format(inv.get(currentDisplay).getPrice())));
    fields[5].setText(String.valueOf(nf.format(inv.get(currentDisplay).value())));
    fields[6].setText(String.valueOf(nf.format(inv.get(currentDisplay).fee())));
    fields[7].setText(String.valueOf(nf.format(inv.get(currentDisplay).feeValue())));
    fields[8].setText(String.valueOf(nf.format(inv.value())));
    }

    public void actionPerformed(ActionEvent e) {


    }

Answer 1

Sie müssen Ihre GUI-Klasse machen Action implementieren, indem

public class GUI extends JFrame 

public class GUI extends JFrame implements ActionListener

Answer 2

Sie müssen nur die Header-Datei importieren .....

import java.awt.event.ActionListener;