java-JTabbedPane中的选项卡不反映按钮按下时的更改
作者：互联网
在我的GUI的选项卡中,允许用户编辑员工的姓名.该名称也用作选项卡的标签,因此,确认更改后,应更新选项卡以反映此更改,并将新数据写入数据文件.
员工存储在“员工”类的HashMap中.通过迭代遍历ArrayList< String>来填充选项卡.员工姓名,这是通过调用Employees.getNames()方法获得的.用户可以从GUI中输入新名称,然后按更改名称按钮.按钮的ActionListener调用方法changeName(),该方法将HashMap中的旧名称替换为新名称,并更新数据文件.
用户第一次要更改员工姓名时,此方法可以正常工作,但随后的更改会产生错误.似乎包含JTextFields的JPanel(请参见下面的getEmployeeInfoPanel())没有更新参数名称.此参数是员工的当前名称,而新名称是从JTextField获得的.
下面是一个说明此问题的示例.本质上,这些步骤是：
1. old name = Mary is provided when the program starts
2. User changes name in JTextField, so oldName = Mary and newName = Mary S.
3. At this point, oldName should update to Mary S. as it is the new key.
However, oldName remains as Mary so the HashMap cannot be updated again.
该特定屏幕的层次结构为：
JFrame (entire application)
|
-- JPanel EmployeesPanel (this screen)
| |
| -- JPanel (for custom menu bar)
| |
| -- JTabbedPane (one tab for each employee)
| |
| -- JPanel (contains JLabels, JTextField, etc for this employee)
|
-- .....
这是GUI中的相关代码：
public class EmployeesPanel {
private JTabbedPane pane;
private Employees employees;
...
public EmployeesPanel(JPanel panel, Container cards) {
...
pane = new JTabbedPane();
getEmployees();
}
private void getEmployees() {
...
employees = new Employees(properties, EMPLOYEES_TXT);
//ArrayList of all employees' names
names = employees.getNames();
for(String name : names) {
pane.addTab(name, getEmployeeInfoPanel(name));
}
pane.addTab("NEW EMPLOYEE", addEmployeePanel());
}
public JPanel addEmployeePanel() {
...
}
private JPanel getEmployeeInfoPanel(final String name) throws EmployeeException {
JPanel infoPanel = new JPanel();
infoPanel.setLayout(new BoxLayout(infoPanel, BoxLayout.PAGE_AXIS));
JLabel nameLabel = new JLabel("Employee name");
JLabel wageLabel = new JLabel("Employee wage");
final JTextField nameField = new JTextField(name, 30);
final JTextField wageField = new JTextField(employees.getWage(name).toString(), 30);
JButton changeNameButton = new JButton("CHANGE NAME");
JButton changeWageButton = new JButton("CHANGE WAGE");
changeNameButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
try {
String newName = nameField.getText();
employees.changeName(name, newName);
panel.validate();
} catch (EmployeeException e) {
// TODO create popup warning
}
}
});
...
return infoPanel;
}
}
这是Employees类中更改HashMap的代码：
public void changeName(String oldName, String newName) throws EmployeeException {
System.out.println("old name = " + oldName + ", new name = " + newName);
if(employees.containsKey(oldName)) {
BigDecimal wage = employees.get(oldName);
employees.remove(oldName);
employees.put(newName, wage);
names.remove(oldName);
names.add(newName);
prop.remove(oldName);
prop.setProperty(newName, wage.toString());
saveProperties();
System.out.println(names);
} else {
throw new EmployeeException("Could not change name because employee does not exist.");
}
}
这是一个例子.第一个屏幕截图来自程序启动时；员工姓名将填充到适当的选项卡中.第二个屏幕快照是在尝试更改员工姓名之后.如您所见,选项卡的标签没有更改,我认为对validate()的调用可以做到.
(之前)
(按下按钮后)
最后,产生两次按下更改名称按钮的输出,显示名称已在ArrayList中更改：
old name = Mary, new name = Mary S.
[Jane, Bob, Sue, Mary S.]
old name = Mary, new name = Mary S.
653647 [AWT-EventQueue-0] ERROR employees.EmployeeException - Could not change name because employee does not exist.
解决方法:
您可能正在寻找setTitleAt()方法.
附录：为了比较,这是一个sscce,允许进行多次编辑.
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import javax.swing.AbstractAction;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import javax.swing.JTextField;
/**
* @see https://stackoverflow.com/a/11007109/230513
*/
public class TabEdit extends JPanel {
private static final int MAX = 5;
private static final String NAME = "Tab ";
private final JTabbedPane pane = new JTabbedPane();
public TabEdit() {
for (int i = 0; i < MAX; i++) {
pane.add(NAME + String.valueOf(i), new TabContent(i));
}
this.add(pane);
}
private class TabContent extends JPanel {
private TabContent(final int i) {
final JTextField jtf = new JTextField(
"Please edit the name of " + NAME + String.valueOf(i));
this.add(jtf);
jtf.addActionListener(new AbstractAction() {
@Override
public void actionPerformed(ActionEvent e) {
pane.setTitleAt(i, jtf.getText());
}
});
}
@Override
public Dimension getPreferredSize() {
return new Dimension(320, 120);
}
}
private void display() {
JFrame f = new JFrame("TabEdit");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(this);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
new TabEdit().display();
}
});
}
}
标签：jtabbedpane,java,user-interface,swing 来源： https://codeday.me/bug/20191012/1896940.html