我正在尝试使用 xml 节点更新组合框的项目，运行循环时获得节点，但不知何故我无法将它们添加为 ComboBox 的项目
public class XMLtoExcelGUI extends javax.swing.JFrame {
public java.io.File file;
public XMLtoExcelGUI() {
initComponents();
}
public void setProgressBarValue(String s){
jProgressBar1.setString(s);
}
@SuppressWarnings("unchecked")
private void initComponents() {
jLabel1 = new javax.swing.JLabel();
jButton1 = new javax.swing.JButton();
jLabel2 = new javax.swing.JLabel();
jProgressBar1 = new javax.swing.JProgressBar();
jButton3 = new javax.swing.JButton();
jScrollPane1 = new javax.swing.JScrollPane();
jTextPane1 = new javax.swing.JTextPane();
jComboBox1 = new javax.swing.JComboBox();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jLabel1.setText("XMLToExcel");
jButton1.setText("Choose File");
jButton1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jButton1ActionPerformed(evt);
}
});
jLabel2.setText("Select Measures");
jProgressBar1.setStringPainted(true);
jButton3.setText("Get Measure Data");
jScrollPane1.setViewportView(jTextPane1);
jComboBox1.setMaximumRowCount(30);
jComboBox1.setModel(new javax.swing.DefaultComboBoxModel(new String[] {}));
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addContainerGap(137, Short.MAX_VALUE)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 97, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(127, 127, 127))
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addComponent(jProgressBar1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(117, 117, 117))))
.addGroup(layout.createSequentialGroup()
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addComponent(jButton3)
.addGap(0, 0, Short.MAX_VALUE))
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jButton1, javax.swing.GroupLayout.PREFERRED_SIZE, 95, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(jLabel2, javax.swing.GroupLayout.PREFERRED_SIZE, 95, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(27, 27, 27)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jScrollPane1)
.addGroup(layout.createSequentialGroup()
.addComponent(jComboBox1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(0, 0, Short.MAX_VALUE)))))
.addContainerGap())
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 46, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jButton1)
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 65, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(63, 63, 63)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel2, javax.swing.GroupLayout.PREFERRED_SIZE, 22, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(jComboBox1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(28, 28, 28)
.addComponent(jButton3)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 26, Short.MAX_VALUE)
.addComponent(jProgressBar1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap())
);
pack();
}// </editor-fold>
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
final JFileChooser fileDialog = new JFileChooser();
int returnVal = fileDialog.showOpenDialog(this);
if (returnVal == JFileChooser.APPROVE_OPTION) {
file = fileDialog.getSelectedFile();
TestVDT call = new TestVDT(file);
jTextPane1.setText(file.toString());
}
}
public static void main(String args[]) {
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 | InstantiationException | IllegalAccessException | javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(XMLtoExcelGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new XMLtoExcelGUI().setVisible(true);
}
});
}
public javax.swing.JButton jButton1;
public javax.swing.JButton jButton3;
public javax.swing.JComboBox jComboBox1;
public javax.swing.JLabel jLabel1;
public javax.swing.JLabel jLabel2;
public javax.swing.JProgressBar jProgressBar1;
public javax.swing.JScrollPane jScrollPane1;
public javax.swing.JTextPane jTextPane1;
// End of variables declaration
}
public class TestVDT {
public int setNumberOfMeasures = 0;
public String[] Measures = new String[30];
public void setMeasureValues(String S[], int length) {
Vector comboBoxItems = new Vector();
for (int i = 1; i < length; i++) {
comboBoxItems.add(S[i]);
// System.out.println(S[i]);
}
XMLtoExcelGUI call = new XMLtoExcelGUI();
DefaultComboBoxModel defaultComboBoxModel = new DefaultComboBoxModel(comboBoxItems);
call.jComboBox1.setModel(defaultComboBoxModel);
}
public TestVDT(java.io.File FName) {
try {
File f = new File(FName.toString());
FileInputStream fis = new FileInputStream(f);
byte[] ba = new byte[(int) f.length()];
fis.read(ba);
VTDGen vg = new VTDGen();
vg.setDoc(ba);
vg.parse(false);
VTDNav vn = vg.getNav();
FileOutputStream fout = new FileOutputStream("E:\\Data.xls");
HSSFWorkbook workbook = new HSSFWorkbook();
HSSFSheet worksheet = workbook.createSheet("Data");
Row row1 = worksheet.createRow(0);
row1.createCell(0).setCellValue("Measure_id");
row1.createCell(1).setCellValue("Denominator");
row1.createCell(2).setCellValue("Numerator");
row1.createCell(3).setCellValue("exclusion");
row1.createCell(4).setCellValue("performance criteria");
//for(int i=0;i<3;i++)
int rowIndex = 1;
int j = 1;
vn.toElement(VTDNav.FIRST_CHILD);
do {
if (vn.matchElement("practice_data")) {
vn.toElement(VTDNav.FIRST_CHILD);
}
if (vn.matchElement("provider_data")) {
vn.toElement(VTDNav.FIRST_CHILD);
}
if (vn.matchElement("provider_identification")) {
vn.toElement(VTDNav.FIRST_CHILD);
}
if (vn.matchElement("measure")) {
vn.toElement(VTDNav.FIRST_CHILD);
do {
Row row = worksheet.createRow(rowIndex++);
int cellIndex = 0;
String temp = vn.toString(vn.getAttrVal("measure_id"));
System.out.println(temp);
Measures[j] = temp;
row.createCell(cellIndex++).setCellValue(vn.toString(vn.getAttrVal("measure_id")));
System.out.print(" -- ");
System.out.print(vn.toString(vn.getAttrVal("denominator")));
row.createCell(cellIndex++).setCellValue(vn.toString(vn.getAttrVal("denominator")));
System.out.print(" -- ");
System.out.print(vn.toString(vn.getAttrVal("numerator")));
row.createCell(cellIndex++).setCellValue(vn.toString(vn.getAttrVal("numerator")));
System.out.print(" -- ");
System.out.print(vn.toString(vn.getAttrVal("exclusion")));
row.createCell(cellIndex++).setCellValue(vn.toString(vn.getAttrVal("exclusion")));
System.out.print(" -- ");
System.out.println(vn.toString(vn.getAttrVal("performance_rate")));
row.createCell(cellIndex++).setCellValue(vn.toString(vn.getAttrVal("performance_rate")));
setNumberOfMeasures++;
j++;
} while (vn.toElement(VTDNav.NEXT_SIBLING));
}
} while (vn.toElement(VTDNav.NEXT_SIBLING));
System.out.println(setNumberOfMeasures);
workbook.write(fout);
fout.flush();
setMeasureValues(Measures, setNumberOfMeasures);
} catch (Exception e) {
System.out.println("exception occurred ==>" + e);
}
}
@SuppressWarnings("empty-statement")
public static void main(String[] args) {
}
}
默认情况下，Jcombo 框的值为空，当调用函数 setMeasureValues() 时，它应该更新组合框的项目，但事实并非如此
最佳答案
您的 XMLtoExcelGUI 变量(调用)是 setMeasureValues(...) 方法的本地变量。对其引用的对象所做的任何更改都只会反射(reflect)在该本地对象中，而不会反射(reflect)在任何其他类似类型的对象上。猜测，但也许您希望将对显示的 XMLtoExcelGUI 对象的有效引用传递到该方法中。否则，如果这没有帮助，您可能需要通过讲述和展示更多内容来改进您的问题。
是的，我是对的——您正在完全不同的非显示 XMLtoExcelGUI 实例中设置组合框的模型。更改一个实例的状态不会也不应该对另一个实例产生影响。解决方案是更改正确显示实例的状态。
更改此:
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
final JFileChooser fileDialog = new JFileChooser();
int returnVal = fileDialog.showOpenDialog(this);
if (returnVal == JFileChooser.APPROVE_OPTION) {
file = fileDialog.getSelectedFile();
TestVDT call = new TestVDT(file);
jTextPane1.setText(file.toString());
}
}
像这样:
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
final JFileChooser fileDialog = new JFileChooser();
int returnVal = fileDialog.showOpenDialog(this);
if (returnVal == JFileChooser.APPROVE_OPTION) {
file = fileDialog.getSelectedFile();
TestVDT call = new TestVDT(this, file); // ****** changed
jTextPane1.setText(file.toString());
}
然后是这个
public class TestVDT {
public int setNumberOfMeasures = 0;
public String[] Measures = new String[30];
public TestVDT(java.io.File FName) {
类似:
public class TestVDT {
public int setNumberOfMeasures = 0;
public String[] Measures = new String[30];
private XMLtoExcelGUI gui;
public TestVDT(XMLtoExcelGUI gui, java.io.File FName) {
this.gui = gui;
这样您的方法就可以使用对实际显示的 GUI 的引用:
public void setMeasureValues(String S[], int length) {
Vector comboBoxItems = new Vector();
for (int i = 1; i < length; i++) {
comboBoxItems.add(S[i]);
}
// XMLtoExcelGUI call = new XMLtoExcelGUI(); // **** no!
DefaultComboBoxModel defaultComboBoxModel = new DefaultComboBoxModel(comboBoxItems);
// give XMLtoExcelGUI a public method that sets
// its own combo box's model
gui.setComboModel(defaultComboBoxModel);
}
关于java - JComboBox动态更新值，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/30821942/