一旦按下按钮，我希望能够更改选项卡式面板的选项卡上显示的 jpanel 内容。问题是，在动作侦听器内部，我无法访问 JPanel 以禁用它们并启用新的 Jpanel，如果我创建一个方法来调用以创建更改，则构造函数之外的方法无法访问我的 Jpanel。有任何想法吗？
编辑：我已将 declerations 移到构造函数上方，但即使如此，也没有检测到令牌：
编辑2：好吧，在构造函数之外声明它允许我在听众内部使用它们。虽然我不能在构造函数之外使用它们，但侦听器就足够了。谢谢你
公共类 MainFrame 扩展 JFrame {
private JTabbedPane tabPane;
// Add Swing components to content pane
JPanel p1 = new JPanel(new BorderLayout());
JPanel p2 = new JPanel(new BorderLayout());
JPanel p3 = new JPanel(new BorderLayout());
JPanel p4 = new JPanel(new BorderLayout());
//Add subpanels for buttons
JPanel sp1 = new JPanel();
JPanel sp2 = new JPanel();
JPanel sp3 = new JPanel();
JPanel sp4 = new JPanel();
public MainFrame(){
如上所示
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowEvent;
import javax.swing.*;
public class MainFrame extends JFrame {
private JTabbedPane tabPane;
public MainFrame(){
this.setTitle("Final Project");
// Add Swing components to content pane
JPanel p1 = new JPanel(new BorderLayout());
JPanel p2 = new JPanel(new BorderLayout());
JPanel p3 = new JPanel(new BorderLayout());
JPanel p4 = new JPanel(new BorderLayout());
//Add subpanels for buttons
JPanel sp1 = new JPanel();
JPanel sp2 = new JPanel();
JPanel sp3 = new JPanel();
JPanel sp4 = new JPanel();
//Creates buttons
JButton buttonA1 = new JButton("LOAD");
JButton buttonA2 = new JButton("SAVE");
JButton buttonB1 = new JButton("ADD");
JButton buttonB2 = new JButton("DELETE");
JButton buttonC1 = new JButton("PRINT BY NAME");
JButton buttonC2 = new JButton("PRINT BY ID");
JButton buttonC3 = new JButton("PRINT BY DATE");
JButton buttonC4 = new JButton("PRINT BY SIZE");
JButton buttonD1 = new JButton("SEARCH BY NAME");
JButton buttonD2 = new JButton("SEARCH BY ID");
//adds buttons to subpanels, then subpanels to mainpanels
sp1.add(buttonA1);
sp1.add(buttonA2);
sp2.add(buttonB1);
sp2.add(buttonB2);
sp3.add(buttonC1);
sp3.add(buttonC2);
sp3.add(buttonC3);
sp3.add(buttonC4);
sp4.add(buttonD1);
sp4.add(buttonD2);
//Creates and adds text to tabs
JLabel text1 = new JLabel(" " +
"Would you like to load or save customers?");
JLabel text2 = new JLabel(" " +
"Would you like to add or delete a customers?");
JLabel text3 = new JLabel(" " +
"Would you like to print a customer(s)?");
JLabel text4 = new JLabel(" " +
"Would you like to search a customer?");
//places the text in the tabs
p1.add(text1, BorderLayout.CENTER);
p1.add(sp1, BorderLayout.SOUTH );
p2.add(text2, BorderLayout.CENTER);
p2.add(sp2, BorderLayout.SOUTH );
p3.add(text3, BorderLayout.CENTER);
p3.add(sp3, BorderLayout.SOUTH);
p4.add(text4, BorderLayout.CENTER);
p4.add(sp4, BorderLayout.SOUTH);
this.tabPane = new JTabbedPane();
this.tabPane.setSize(750, 50);
this.tabPane.setLocation(10, 10);
tabPane.addTab("Load or Save", null, p1, "This is where you can load " +
" or save a file.");
tabPane.addTab("Add or delete",null , p2, "This is where you add " +
"or delete a customer.");
tabPane.addTab("print",null , p3, "this is where you print" +
" one or more customers.");
tabPane.addTab("search",null , p4, "This is where you can " +
"search customers.");
this.setVisible(true);
this.setSize(500, 400);
this.setLocation(400, 300);
this.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
this.setVisible(true);
Container c = getContentPane();
c.add(tabPane);
///////////////////////////////////////////////////////////////
// BUTTON LISTNERS
///////////////////////////////////////////////////////////////
// Add behaviour to button.
buttonA1.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
}
});
// Add behaviour to button.
buttonA2.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
}
});
// Add behaviour to button.
buttonB1.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
//method that would disable the panel
disableP1();
//then would create a new panel to take its place.
}
});
// Add behaviour to button.
buttonB2.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
}
});
// Add behaviour to button.
buttonC1.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
}
});
// Add behaviour to button.
buttonC2.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
}
});
// Add behaviour to button.
buttonC3.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
}
});
// Add behaviour to button.
buttonC4.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
}
});
// Add behaviour to button.
buttonD1.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
}
});
// Add behaviour to button.
buttonD2.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
}
});
}
public void close(){
WindowEvent winClosingEvent = new WindowEvent(this,WindowEvent.WINDOW_CLOSING);
Toolkit.getDefaultToolkit().getSystemEventQueue().postEvent(winClosingEvent);
}
public static void disableP1(){
}
}