nxn - matriz dinamica java

Java no puede encontrar el símbolo, ¿Java no puede encontrar mi símbolo en una matriz?

Question

Este es el error que recibo cuando escribo esta línea de código.

symbol  : variable isSeletecd
location: class java.lang.String
if (dorm[0].isSeletecd && meal[0].isSeletecd())
           ^

if (dorm[0].isSeletecd && meal[0].isSeletecd())
totalCharges.setText("2150.00");

Programa:

import java.awt.BorderLayout; 
import java.awt.event.ActionEvent; 
import java.awt.event.ActionListener; 
import javax.swing.JButton; 
import javax.swing.JComboBox; 
import javax.swing.JFrame; 
import javax.swing.JLabel; 
import javax.swing.JPanel; 
import javax.swing.JTextField; 

/** 

The Main class creates the GUI for the Dorm and 
Meal charges. 
*/ 

public class Main extends JFrame 
{ 
private JPanel dormPanel; 
private JComboBox dormBox; 
private JPanel mealPanel; 
private JComboBox mealBox; 
private JPanel totalChargesPanel; 
private JPanel selectedMealPanel; 
private JPanel buttonPanel; 
private JButton calcButton; 
private JLabel label1; 
private JTextField totalCharges; 

private String[] dorm = { "Allen Hall: $1,500 per semester", 
"Pike Hall: $1,600 per semester", 
"Farthing Hall: $1,200 per semester", 
"University Suites: $1,800 pe r semester"}; 

private String[] meal = { "7 meals per week: $650 per semester", 
"14 meals per week: $1,095 per semester", 
"Unlimited meals: $1,500 per semester"}; 

/** 
Constructor 
*/ 
public Main() 
{ 
super("Dormitory and Meal Plan"); 

// Specify an action for the close button. 
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 

// Create a BorderLayout manager. 
setLayout(new BorderLayout()); 

// Create the dorm and meal panel. 
buildDormPanel(); 
buildMealPanel(); 
buildSelectedTotalChargesPanel(); 
buildButtonPanel(); 

// Add the components to the content pane. 
add(dormPanel, BorderLayout.WEST); 
add(mealPanel, BorderLayout.EAST); 
add(totalChargesPanel, BorderLayout.SOUTH); 
add(buttonPanel, BorderLayout.NORTH); 

// Pack the contents of the window and display it. 
pack(); 
setVisible(true); 
} 

// The buildDormPanel method builds the dorm panel. 
private void buildDormPanel() 
{ 
// Create the dorm panel. 
dormPanel = new JPanel(); 
dormBox = new JComboBox(dorm); 

// Register the action listener. 
dormBox.addActionListener(new ComboBoxListener()); 

// Add the dorm panel to the panel. 
dormPanel.add(dormBox); 
} 

// The buildMealPanel method builds the meal panel. 
private void buildMealPanel() 
{ 
// Create the meal panel. 
mealPanel = new JPanel(); 
mealBox = new JComboBox(meal); 

// Register the action listener. 
mealBox.addActionListener(new ComboBoxListener()); 

// Add the meal panel to the panel. 
mealPanel.add(mealBox); 
} 

// The buttonPanel method builds the bottun panel. 
private void buildButtonPanel() 
{ 
// Create a panel. 
buttonPanel = new JPanel(); 

// Create a button. 
calcButton = new JButton("Calculate"); 

// Register an action listener with the button. 
calcButton.addActionListener(new ButtonListener()); 

// Add the button to the panel. 
buttonPanel.add(calcButton); 
} 

// The buildSelectedDormPanel builds the selected totalCharges panel. 
private void buildSelectedTotalChargesPanel() 
{ 
// Create the totalChargesPanel for the label. 
totalChargesPanel = new JPanel(); 
label1 = new JLabel("Total charges per semester: "); 

// Create the totalCharges textfield. 
totalCharges = new JTextField (25); 
totalCharges.setEditable(false); 

// Add the totalChargesPanel to the panel. 
totalChargesPanel.add(label1); 
totalChargesPanel.add(totalCharges); 
} 

/** Private inner class that handles the event when the user 
selects the dorm and meal boxes. 
*/ 
private class ComboBoxListener implements ActionListener 
{ 
public void actionPerformed(ActionEvent e) 
{ 
// Variables to hold the dorm, meal, and total charges. 
String dorm = (String) dormBox.getSelectedItem(); 
String meal = (String) mealBox.getSelectedItem(); 

// Calculates the total. 
totalCharges.setText(meal + dorm); 
} 
} 

private class ButtonListener implements ActionListener 
{ 
public void actionPerformed(ActionEvent e) 
{ 
if (dorm[0].isSeletecd && meal[0].isSeletecd())
totalCharges.setText("2150.00");
} 
} 

public static void main(String[] args) 
{ 
new Main(); 
} 
} 

Answer 1

dorm y la meal son matrices de cadenas, no hay campos isSelected() o isSelected() en java.lang.String .

Answer 2

dorm y meal son matrices de cuerdas

No hay isSelected() método isSelected() para la clase String , pero hay un método getSelectedIndex() para JComboBox que se puede usar para obtener el índice no del elemento seleccionado actualmente en el componente JComboBox .

Al reemplazar la condición en la instrucción if en su clase ButtonListener

de

if (dorm[0].isSeletecd && meal[0].isSeletecd())

a

if(dormBox.getSelectedIndex()==0 && mealBox.getSelectedIndex()==0)

resolverá tu problema

Entonces su clase ButtonListener ahora será

private class ButtonListener implements ActionListener { 
    public void actionPerformed(ActionEvent e) { 
        if(dormBox.getSelectedIndex()==0 && mealBox.getSelectedIndex()==0)
            totalCharges.setText("2150.00");
    } 
} 

getSelectedIndex() para más información.