SwingPropertyChangeSupport para actualizar dinámicamente JTextArea

Resuelto Robert asked hace 12 años • 3 respuestas

Estoy intentando aprovechar la respuesta a una pregunta sobre SwingPropertyChangeSupport

Estoy intentando modificar el código proporcionado aquí en una respuesta del muy útil Hovercraft Full Of Eels: WindowListener no funciona como se esperaba. , para permitir que una matriz mostrada se actualice cuando se ingresan cambios a través de un cuadro de diálogo de entrada.

La matriz se actualiza correctamente pero no se actualiza en la GUI. Esperaba que alguien pudiera decirme dónde me equivoqué.

aquí está el código:

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusListener;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.event.SwingPropertyChangeSupport;

public class Main {
public static void main(String[] arg) {
    GuiForUpdate display = new GuiForUpdate();
    display.setVisible(true);
}
}

class GuiForUpdate extends JFrame implements ActionListener {

/**
 * 
 */
private static final long serialVersionUID = 1L;
private FocusListener focusListener;
private String mList;
private JButton changeArrayButton;
private JTextArea codeIn, displayOutput;
private int arrayIndex;
private JPanel displayPanel;
private ArrayForUpdating arrayForUpdate = new ArrayForUpdating();

public GuiForUpdate() {
    setSize(224, 180);
    layoutLeft();
    layoutDisplay();
    layoutBottom();
}

/**
 * adds a display area for array
 */
public void layoutDisplay() {
    displayPanel = new JPanel();
    add(displayPanel, BorderLayout.CENTER);
    displayOutput = new JTextArea();
    displayPanel.add(displayOutput);
    displayOutput.addFocusListener(focusListener);

    mList = arrayForUpdate.getBoundProperty();

    arrayForUpdate.addPropertyChangeListener(new PropertyChangeListener() {

        @Override
        public void propertyChange(PropertyChangeEvent pcEvt) {
            if (pcEvt.getPropertyName().equals(
                    ArrayForUpdating.BOUND_PROPERTY)) {
                mList = (pcEvt.getNewValue().toString());
            }
        }
    });

    displayOutput.setText(mList);
}

/**
 * adds left hand side elements to left of GUI
 */
public void layoutLeft() {
    JPanel left = new JPanel();
    add(left, BorderLayout.WEST);
    codeIn = new JTextArea(2, 2);
    left.add(codeIn);
    codeIn.addFocusListener(focusListener);
}

/**
 * adds bottom elements to bottom of GUI
 */
public void layoutBottom() {
    JPanel bottom = new JPanel();
    changeArrayButton = new JButton("Modify array");
    changeArrayButton.addActionListener(this);
    bottom.add(changeArrayButton);
    add(bottom, BorderLayout.SOUTH);
}

/**
 * Process button clicks
 */
public void actionPerformed(ActionEvent ae) {

    if (ae.getSource() == changeArrayButton) {

        // first check if any code entered
        if (codeIn.getText().trim().length() != 0) {

            // call modifyMemory() method
            modifyArray();

        } else
            JOptionPane.showMessageDialog(null,
                    "Please enter something first.");
    }
}

/**
 * method to process modify array
 */
public void modifyArray() {

    // show dialog to retrieve entered address
    String addressToModify = (String) JOptionPane
            .showInputDialog("At which location?");

    // confirm if a string was entered
    if ((addressToModify != null) && (addressToModify.length() > 0)) {

        // convert to integer if decimal address entered
        arrayIndex = Integer.parseInt(addressToModify);
    }
    // pass as integer
    processInput(arrayIndex);
}

public void processInput(int a) {

    String newValue = codeIn.getText();
    arrayForUpdate.instructionsIn(newValue, a);
}
}

class ArrayForUpdating {

public static final String BOUND_PROPERTY = "bound property";
private String boundProperty = "";

private SwingPropertyChangeSupport spcSupport = new SwingPropertyChangeSupport(
        this);
private StringBuilder mList;
private int[] myArray;

public ArrayForUpdating() {

    myArray = new int[5];
    for (int i = 0; i < myArray.length; i++) {
        myArray[i] = 0;
    }
    setArrayyDisplayString();
}

/** 
 * method to create formatted string of array
 */
public void setArrayyDisplayString() {

    // create StringBuilder for display in memory tab
    mList = new StringBuilder();
    for (int i = 0; i < myArray.length; i++) {

        mList.append(String.format("%10s %02d %10s %02d", "Pos:   ", i,
                "Value:  ", myArray[i]));
        mList.append("\n");
    }
    setBoundProperty(mList.toString());
}

/**
 * This method takes in a string passed through from the GUI
 */
public void instructionsIn(String codeIn, int loc) {

    String code = codeIn.trim();
    int oc = Integer.parseInt(code);

    // add the data to the array
    setArrayData(loc, oc);
    loc++;
}

/**   
 * method to add data to the array
 */
public void setArrayData(int a, int memData) {
    myArray[a] = memData;

    // print array to console for checking
    for (int i = 0; i < myArray.length; i++) {
        System.out.println("location: " + i + " value: " + myArray[i]);
    }
    setArrayyDisplayString();
}

public SwingPropertyChangeSupport getSpcSupport() {
    return spcSupport;
}

public void setSpcSupport(SwingPropertyChangeSupport spcSupport) {
    this.spcSupport = spcSupport;
}

public String getBoundProperty() {
    return boundProperty;
}

public void setBoundProperty(String boundProperty) {
        String oldValue = this.boundProperty;
        System.out.println("old = " + oldValue);
        String newValue = boundProperty;
        System.out.println("new = " + newValue);
        this.boundProperty = newValue;
        spcSupport.firePropertyChange(BOUND_PROPERTY, oldValue, newValue);
    }

    public void addPropertyChangeListener(PropertyChangeListener listener) {
    spcSupport.addPropertyChangeListener(listener);
    }
}

-EDITAR- Con suerte se eliminaron los errores de compilación.

Robert avatar Aug 06 '12 18:08 Robert
Aceptado

A continuación se muestra un ejemplo completo que se utiliza ObservedPanelen un diálogo no modelo.

public class PropertyChangeDialog extends JPanel {

    private JLabel label = new JLabel("null", JLabel.CENTER);
    private ObservedPanel observed = new ObservedPanel();

    public PropertyChangeDialog() {
        this.setBorder(BorderFactory.createTitledBorder("Observer"));
        this.add(label);
        observed.addPropertyChangeListener(new PropertyChangeListener() {

            @Override
            public void propertyChange(PropertyChangeEvent e) {
                if (e.getPropertyName().equals(ObservedPanel.PHYSICIST)) {
                    String value = e.getNewValue().toString();
                    label.setText(value);
                }
            }
        });
    }

    private void display() {
        JFrame f = new JFrame("PropertyChangeDialog");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(this);
        f.pack();
        f.setLocationByPlatform(true);
        f.setVisible(true);
        JDialog dialog = new JDialog(f);
        dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
        dialog.add(observed);
        dialog.pack();
        dialog.setLocationRelativeTo(null);
        dialog.setVisible(true);
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                new PropertyChangeDialog().display();
            }
        });
    }
}
trashgod avatar Aug 06 '2012 17:08 trashgod

El código parece más o menos correcto (es decir, no pude encontrar ningún error obvio). Deberías intentar ejecutarlo en el depurador y hacer una nueva pregunta cuando te quedes atascado al depurar el código.

Aaron Digulla avatar Aug 06 '2012 12:08 Aaron Digulla

Cuando introduje displayOutput.setText(mList)el propertyChangemétodo, funcionó:

@Override
public void propertyChange(PropertyChangeEvent pcEvt) {
    if (pcEvt.getPropertyName().equals(
        ArrayForUpdating.BOUND_PROPERTY)) {
        mList = (pcEvt.getNewValue().toString());
        displayOutput.setText(mList);
    }
}

Gracias a todos por su ayuda y especialmente su paciencia.

Robert avatar Aug 06 '2012 23:08 Robert