我无法理解为什么这段代码不起作用，下面是我尝试在JTable上调用单元格值的代码中的方法。单击该行时，代码将获取该行并使用该行中的信息，并且应该使用该信息填充JTextBoxes。调试器没有帮助，因为它只指向第一个getValueAt（）并将其称为NullPointerException。
private void editInfoButtonActionPerformed(java.awt.event.ActionEvent evt) {
System.out.println("Opening 'Edit Info' window.");
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new editPatientDialogBox().setVisible(true);
}
});
editPatientDialogBox.roomNumberField.setText(bedboard.patientInfoTable.getValueAt(bedboard.patientInfoTable.getSelectedRow(),0).toString());
editPatientDialogBox.nameField.setText(bedboard.patientInfoTable.getValueAt(bedboard.patientInfoTable.getSelectedRow(),1).toString());
editPatientDialogBox.genderField.setSelectedItem(bedboard.patientInfoTable.getValueAt(bedboard.patientInfoTable.getSelectedRow(),2).toString());
editPatientDialogBox.dateAdmittedField.setText(bedboard.patientInfoTable.getValueAt(bedboard.patientInfoTable.getSelectedRow(),3).toString());
editPatientDialogBox.ageField.setText(bedboard.patientInfoTable.getValueAt(bedboard.patientInfoTable.getSelectedRow(),4).toString());
editPatientDialogBox.isolationField.setSelectedItem(bedboard.patientInfoTable.getValueAt(bedboard.patientInfoTable.getSelectedRow(),5).toString())
这是它正在调用的类本身
public class editPatientDialogBox extends javax.swing.JFrame {
public editPatientDialogBox() {
initComponents();
}
@SuppressWarnings("unchecked")
private void initComponents() {
roomNumberField = new javax.swing.JTextField();
roomNumberLabel = new javax.swing.JLabel();
nameField = new javax.swing.JTextField();
nameLabel = new javax.swing.JLabel();
genderField = new javax.swing.JComboBox();
genderLabel = new javax.swing.JLabel();
acceptButton = new javax.swing.JButton();
isolationField = new javax.swing.JComboBox();
isolationLabel = new javax.swing.JLabel();
ageField = new javax.swing.JTextField();
dateAdmittedField = new javax.swing.JTextField();
cancelButton = new javax.swing.JButton();
dateAdmittedLabel = new javax.swing.JLabel();
ageLabel = new javax.swing.JLabel();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
roomNumberLabel.setText("Room Number");
nameLabel.setText("Patient Name");
genderField.setMaximumRowCount(2);
genderField.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "Male", "Female" }));
genderLabel.setText("Gender");
acceptButton.setText("Accept");
acceptButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
acceptButtonActionPerformed(evt);
}
});
isolationField.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "Yes", "No" }));
isolationLabel.setText("Isolation");
ageField.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
ageFieldActionPerformed(evt);
}
});
dateAdmittedField.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
dateAdmittedFieldActionPerformed(evt);
}
});
cancelButton.setText("Cancel");
cancelButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
cancelButtonActionPerformed(evt);
}
});
dateAdmittedLabel.setText("Date Admitted (YYYY/MM/DD)");
ageLabel.setText("Date of Birth (YYYY/MM/DD)");
private void acceptButtonActionPerformed(java.awt.event.ActionEvent evt) {
if(bedboard.patientInfoTable.getValueAt(bedboard.patientInfoTable.getSelectedRow(),bedboard.patientInfoTable.getSelectedRow()) == null)
{
System.out.println("None selected, try again.");
}
else
{
String get = null;
info.setRoom(roomNumberField.getText());
info.setPatientName(nameField.getText());
info.setGender(genderField.getSelectedItem().toString());
info.setDateAd(dateAdmittedField.getText());
info.setAge(ageField.getText());
info.setIso(isolationField.getSelectedItem().toString());
setVisible(false);
System.out.println("*********************************************************************************************");
System.out.println("REVISED PATIENT");
System.out.println("Patient Name: " + nameField.getText());
System.out.println("Room Number: " + roomNumberField.getText());
System.out.println("Gender: " + genderField.getSelectedItem());
System.out.println("Date Admitted: " + dateAdmittedField.getText());
System.out.println("Age: " + ageField.getText());
System.out.println("Isolation: " + isolationField.getSelectedItem());
System.out.println("*********************************************************************************************");
bedboard.setValue(info.getRoom(get),bedboard.patientInfoTable.getSelectedRow(),0);
bedboard.setValue(info.getPatientName(get),bedboard.patientInfoTable.getSelectedRow(),1);
bedboard.setValue(info.getGender(get),bedboard.patientInfoTable.getSelectedRow(),2);
bedboard.setValue(info.getDateAd(get),bedboard.patientInfoTable.getSelectedRow(),3);
bedboard.setValue(info.getAge(get),bedboard.patientInfoTable.getSelectedRow(),4);
bedboard.setValue(info.getIso(get),bedboard.patientInfoTable.getSelectedRow(),5);
}
}
private void ageFieldActionPerformed(java.awt.event.ActionEvent evt) {
}
private void dateAdmittedFieldActionPerformed(java.awt.event.ActionEvent evt) {
}
private void cancelButtonActionPerformed(java.awt.event.ActionEvent evt) {
System.out.println("Revise patient canceled.");
setVisible(false);
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
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(editPatientDialogBox.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(editPatientDialogBox.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(editPatientDialogBox.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(editPatientDialogBox.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new editPatientDialogBox().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JButton acceptButton;
public static javax.swing.JTextField ageField;
private javax.swing.JLabel ageLabel;
private javax.swing.JButton cancelButton;
public static javax.swing.JTextField dateAdmittedField;
private javax.swing.JLabel dateAdmittedLabel;
public static javax.swing.JComboBox genderField;
private javax.swing.JLabel genderLabel;
public static javax.swing.JComboBox isolationField;
private javax.swing.JLabel isolationLabel;
public static javax.swing.JTextField nameField;
private javax.swing.JLabel nameLabel;
public static javax.swing.JTextField roomNumberField;
private javax.swing.JLabel roomNumberLabel;
// End of variables declaration
}
老实说，我不知道该怎么做。如果您需要更多信息，请发表评论
答案 0 :(得分：2)
为什么使用invokeLater(...) ???
该方法将代码添加到Event Dispatch Thread的末尾，这意味着它在所有setText（）语句之后执行。摆脱invokeLater（）。
此外，editPatientDialogBox变量在哪里初始化。您的代码只调用new EditPatientDialogBox()，但不会将创建的对象分配给任何变量。
我希望代码应该是：
EditPatientDialogBox editPatiendDialogBox = new EditPatientDialogBox(); // note the capital "E" of the class name.
editPatientDialogBox.roomNumberField.setText(bedboard.patientInfoTable.getValueAt(bedboard.patientInfoTable.getSelectedRow(),0).toString());
...
editPatientDialogBox.setVisible(true);
此外，类名应以大写字母开头。修复你的班级名称。