Java 如何使用自定义组件属性？_Java_User Interface

Java 如何使用自定义组件属性？

java user-interface

Java 如何使用自定义组件属性？,java,user-interface,Java,User Interface,如果我使用自定义组件属性，我在尝试用java创建事件时遇到问题。我创建了一个数字时钟，我有一个闹钟，我想抛出一个事件，但当我运行我的程序时，它没有，因为一个异常： Exception in thread "Timer-0" java.lang.NullPointerException at proyectoreloj.ProyectoReloj$1.run(ProyectoReloj.java:73) at java.util.TimerThread.mainLoop(Timer.java:55

如果我使用自定义组件属性，我在尝试用java创建事件时遇到问题。我创建了一个数字时钟，我有一个闹钟，我想抛出一个事件，但当我运行我的程序时，它没有，因为一个异常：

Exception in thread "Timer-0" java.lang.NullPointerException
at proyectoreloj.ProyectoReloj$1.run(ProyectoReloj.java:73)
at java.util.TimerThread.mainLoop(Timer.java:555)
at java.util.TimerThread.run(Timer.java:505)

我的代码是：

public class ProyectoReloj extends JLabel implements Serializable
{

int hora, minutos;
boolean formato24h = false;
private Alarma alarma;
private AlarmaInterfaz alarmaInterfaz;

public ProyectoReloj()
{}


public Alarma getAlarma() {
    return alarma;
}


public void setAlarma(Alarma alarma) {
    this.alarma = alarma;
}


public boolean isFormato24h() {
    return formato24h;
}

public void setFormato24h(boolean formato24h) {
    this.formato24h = formato24h;
}


public void setAlarmaInterfaz(AlarmaInterfaz alarmaInterfaz) {
    this.alarmaInterfaz = alarmaInterfaz;
}


public void start()
{
    Timer timer = new Timer();
    timer.schedule(new TimerTask()
    {
        @Override
        public void run()
        {
            Calendar calendario = Calendar.getInstance();
            hora = Calendar.HOUR;
            minutos = Calendar.MINUTES;
            if(formato24h == false)
            {

                SimpleDateFormat formato = new SimpleDateFormat("hh:mm:ss");
                setText(formato.format(calendario.getTime()));
            }
            else
            {
                SimpleDateFormat formato = new SimpleDateFormat("HH:mm:ss");
                setText(formato.format(calendario.getTime()));
            }

            if((hora == getAlarma().getHora()) && (minutos == getAlarma().getMinutos()))
            {
                alarmaInterfaz.ejecutaAlarma();
            }
        }
    },0,1000);
}
}

下面的类是我检查组件的地方

/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/

package relojprueba;

import proyectoreloj.AlarmaInterfaz;

/**
 *
 * @author Amaro
 */
public class NewJFrame extends javax.swing.JFrame {

/**
 * Creates new form NewJFrame
 */
public NewJFrame() {
    initComponents();
    proyectoReloj2.start();
    proyectoReloj2.setAlarmaInterfaz(new AlarmaInterfaz()
    {
        @Override
        public void ejecutaAlarma()
        {
            System.out.println("Esto es la alarma");                    
        }
    });
}

/**
 * This method is called from within the constructor to initialize the form.
 * WARNING: Do NOT modify this code. The content of this method is always
 * regenerated by the Form Editor.
 */
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">                          
private void initComponents() {

    proyectoReloj1 = new proyectoreloj.ProyectoReloj();
    proyectoReloj2 = new proyectoreloj.ProyectoReloj();

    proyectoReloj1.setText("proyectoReloj1");

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

    proyectoReloj2.setText("proyectoReloj2");

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addGap(149, 149, 149)
            .addComponent(proyectoReloj2, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addContainerGap(178, Short.MAX_VALUE))
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addGap(131, 131, 131)
            .addComponent(proyectoReloj2, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addContainerGap(155, Short.MAX_VALUE))
    );

    pack();
}// </editor-fold>                        

/**
 * @param args the command line arguments
 */
public static void main(String args[]) {
    /* Set the Nimbus look and feel */
    //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
    /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
     * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
     */
    try {
        for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
            if ("Nimbus".equals(info.getName())) {
                javax.swing.UIManager.setLookAndFeel(info.getClassName());
                break;
            }
        }
    } catch (ClassNotFoundException ex) {
        java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (InstantiationException ex) {
        java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (IllegalAccessException ex) {
        java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    }
    //</editor-fold>

    /* Create and display the form */
    java.awt.EventQueue.invokeLater(new Runnable() {
        public void run() {
            new NewJFrame().setVisible(true);
        }
    });
}

// Variables declaration - do not modify                     
private proyectoreloj.ProyectoReloj proyectoReloj1;
private proyectoreloj.ProyectoReloj proyectoReloj2;
// End of variables declaration                   
}

/*
*要更改此许可证标题，请在“项目属性”中选择“许可证标题”。
*要更改此模板文件，请选择工具|模板
*然后在编辑器中打开模板。
*/
包装重新包装；
进口proyectoreloj.AlarmaInterfaz；
/**
*
*@作者阿马罗
*/
公共类NewJFrame扩展了javax.swing.JFrame{
/**
*创建新表单NewJFrame
*/
公共NewJFrame（）{
初始化组件（）；
proyectoReloj2.start（）；
ProyectorObj2.setAlarmaInterfaz（新的AlarmaInterfaz（）
{
@凌驾
public void ejectaarma（）
{
System.out.println（“Esto es la alarma”）；
}
});
}
/**
*从构造函数中调用此方法来初始化表单。
*警告：不要修改此代码。此方法的内容始终为
*由表单编辑器重新生成。
*/
@抑制警告（“未选中”）
//                           
私有组件（）{
proyectoReloj1=新建proyectoreloj.proyectoreloj（）；
proyectoReloj2=新建proyectoreloj.proyectoreloj（）；
proyectoReloj1.setText（“proyectoReloj1”）；
setDefaultCloseOperation（javax.swing.WindowConstants.EXIT_ON_CLOSE）；
proyectoReloj2.setText（“proyectoReloj2”）；
javax.swing.GroupLayout=newjavax.swing.GroupLayout（getContentPane（））；
getContentPane（）.setLayout（布局）；
layout.setHorizontalGroup(
createParallelGroup（javax.swing.GroupLayout.Alignment.LEADING）
.addGroup（layout.createSequentialGroup（）
.addGap（149149149）
.addComponent（proyectorObj2、javax.swing.GroupLayout.PREFERRED\u SIZE、javax.swing.GroupLayout.DEFAULT\u SIZE、javax.swing.GroupLayout.PREFERRED\u SIZE）
.addContainerGap（178，简称最大值））
);
layout.setVerticalGroup(
createParallelGroup（javax.swing.GroupLayout.Alignment.LEADING）
.addGroup（layout.createSequentialGroup（）
.addGap（131131131）
.addComponent（proyectorObj2、javax.swing.GroupLayout.PREFERRED\u SIZE、javax.swing.GroupLayout.DEFAULT\u SIZE、javax.swing.GroupLayout.PREFERRED\u SIZE）
.addContainerGap（155，简称最大值））
);
包装（）；
}//                         
/**
*@param指定命令行参数
*/
公共静态void main（字符串参数[]）{
/*设置Nimbus的外观和感觉*/
//
/*如果Nimbus（在JavaSE6中引入）不可用，请使用默认的外观。
*详情请参阅http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
*/
试一试{
for（javax.swing.UIManager.LookAndFeelInfo:javax.swing.UIManager.getInstalledLookAndFeels（））{
if（“Nimbus”.equals（info.getName（）））{
setLookAndFeel（info.getClassName（））；
打破
}
}
}捕获（ClassNotFoundException ex）{
getLogger（NewJFrame.class.getName（））.log（java.util.logging.Level.SEVERE，null，ex）；
}catch（实例化异常）{
getLogger（NewJFrame.class.getName（））.log（java.util.logging.Level.SEVERE，null，ex）；
}捕获（非法访问例外）{
getLogger（NewJFrame.class.getName（））.log（java.util.logging.Level.SEVERE，null，ex）；
}catch（javax.swing.UnsupportedLookAndFeelException ex）{
getLogger（NewJFrame.class.getName（））.log（java.util.logging.Level.SEVERE，null，ex）；
}
//
/*创建并显示表单*/
invokeLater（new Runnable（））{
公开募捐{
新建NewJFrame（）.setVisible（true）；
}
});
}
//变量声明-不修改
私有proyectoreloj.proyectoreloj proyectoReloj1；
私人项目2；
//变量结束声明
}

ProyectoReloj.alarma

为空。您不能调用

ProyectoReloj.setAlarma

。您需要在启动计时器之前设置它，或者您应该在run方法中选中

getAlarm（）==null

，您有以下代码：

        if((hora == getAlarma().getHora()) && (minutos == getAlarma().getMinutos()))
        {
            alarmaInterfaz.ejecutaAlarma();
        }

我猜getAlarma（）将返回null（您不初始化该值），而getHora调用将导致NPE

此外，与每秒检查一次警报不同，您应该构建计时器，使其仅在警报关闭时唤醒（即从现在到警报关闭时间之间的计算毫秒）

问题的可能重复之处在于，我在AlarmaPanel类中设置了警报，该类警报是一个带有两个JTextField的JPanel，第一个是小时，第二个是分钟。我以为闹钟是在我按下thar JPanel中的“ok”时设置的，所以我不知道如何设置闹钟。

public class AlarmaPanel extends javax.swing.JPanel {

/**
 * Creates new form AlarmaPanel
 */
public AlarmaPanel() {
    initComponents();
}

public Alarma getAlarm()
{
    if(!horasField.getText().equalsIgnoreCase("") && minutosField.getText().equalsIgnoreCase(""))
    {
        int horas = Integer.parseInt(horasField.getText());
        int minutos = Integer.parseInt(minutosField.getText());
        return new Alarma(horas, minutos);
    }
    return null;
}

/**
 * This method is called from within the constructor to initialize the form.
 * WARNING: Do NOT modify this code. The content of this method is always
 * regenerated by the Form Editor.
 */
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">                          
private void initComponents() {

    horasField = new javax.swing.JTextField();
    minutosField = new javax.swing.JTextField();
    jLabel1 = new javax.swing.JLabel();
    jLabel2 = new javax.swing.JLabel();

    horasField.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            horasFieldActionPerformed(evt);
        }
    });

    jLabel1.setText(":");

    jLabel2.setText("ALARMA");

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
    this.setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
            .addComponent(jLabel2)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addComponent(horasField, javax.swing.GroupLayout.PREFERRED_SIZE, 21, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(jLabel1)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(minutosField, javax.swing.GroupLayout.PREFERRED_SIZE, 21, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addGap(55, 55, 55))
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                .addComponent(horasField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addComponent(minutosField, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addComponent(jLabel1)
                .addComponent(jLabel2))
            .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
    );
}// </editor-fold>                        

private void horasFieldActionPerformed(java.awt.event.ActionEvent evt) {                                           
    // TODO add your handling code here:
}                                          


// Variables declaration - do not modify                     
private javax.swing.JTextField horasField;
private javax.swing.JLabel jLabel1;
private javax.swing.JLabel jLabel2;
private javax.swing.JTextField minutosField;
// End of variables declaration                   
}

public class RelojPropertyEditorSupport extends PropertyEditorSupport
{
private AlarmaPanel alarmaPanel = new AlarmaPanel();

@Override
public boolean supportsCustomEditor()
{
    return true;
}

@Override
public Component getCustomEditor()
{
    return alarmaPanel;
}

@Override
public Object getValue()
{
    return alarmaPanel.getAlarm();
}


@Override
public String getJavaInitializationString()
{
    int horas = alarmaPanel.getAlarm().getHora();
    int minutos = alarmaPanel.getAlarm().getMinutos();
    return "new proyectoreloj.Alarma("+horas+","+ minutos+")";
}
}

/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/

package relojprueba;

import proyectoreloj.AlarmaInterfaz;

/**
 *
 * @author Amaro
 */
public class NewJFrame extends javax.swing.JFrame {

/**
 * Creates new form NewJFrame
 */
public NewJFrame() {
    initComponents();
    proyectoReloj2.start();
    proyectoReloj2.setAlarmaInterfaz(new AlarmaInterfaz()
    {
        @Override
        public void ejecutaAlarma()
        {
            System.out.println("Esto es la alarma");                    
        }
    });
}

/**
 * This method is called from within the constructor to initialize the form.
 * WARNING: Do NOT modify this code. The content of this method is always
 * regenerated by the Form Editor.
 */
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">                          
private void initComponents() {

    proyectoReloj1 = new proyectoreloj.ProyectoReloj();
    proyectoReloj2 = new proyectoreloj.ProyectoReloj();

    proyectoReloj1.setText("proyectoReloj1");

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

    proyectoReloj2.setText("proyectoReloj2");

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addGap(149, 149, 149)
            .addComponent(proyectoReloj2, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addContainerGap(178, Short.MAX_VALUE))
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addGap(131, 131, 131)
            .addComponent(proyectoReloj2, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addContainerGap(155, Short.MAX_VALUE))
    );

    pack();
}// </editor-fold>                        

/**
 * @param args the command line arguments
 */
public static void main(String args[]) {
    /* Set the Nimbus look and feel */
    //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
    /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
     * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
     */
    try {
        for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
            if ("Nimbus".equals(info.getName())) {
                javax.swing.UIManager.setLookAndFeel(info.getClassName());
                break;
            }
        }
    } catch (ClassNotFoundException ex) {
        java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (InstantiationException ex) {
        java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (IllegalAccessException ex) {
        java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    }
    //</editor-fold>

    /* Create and display the form */
    java.awt.EventQueue.invokeLater(new Runnable() {
        public void run() {
            new NewJFrame().setVisible(true);
        }
    });
}

// Variables declaration - do not modify                     
private proyectoreloj.ProyectoReloj proyectoReloj1;
private proyectoreloj.ProyectoReloj proyectoReloj2;
// End of variables declaration                   
}

        if((hora == getAlarma().getHora()) && (minutos == getAlarma().getMinutos()))
        {
            alarmaInterfaz.ejecutaAlarma();
        }