如何使用java（netbeans）禁用和启用按钮。让我假设我有一个按钮名称LiveMonitoring并在jtextarea上有一些ipadrress输出。我想要的是Live Monitoring应该被禁用到那个程度，直到我选择textarea上的一些ipaddress。我这样做首先我已经通过LiveMonitoring.setEnabled（false）禁用了按钮，并且只要我选择了一些文本
package zeeshannisar210;
import java.awt.List;
import java.awt.event.ActionEvent;
import java.awt.event.MouseEvent;
import java.io.IOException;
import java.net.Socket;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.Scanner;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JCheckBox;
import javax.swing.JOptionPane;
import javax.swing.JTextField;
public class Home extends javax.swing.JFrame {
JCheckBox sh1;
static Socket csocket;
public Home()
{
initComponents();
}
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jPanel2 = new javax.swing.JPanel();
Home = new javax.swing.JButton();
LiveMonitoring = new javax.swing.JButton();
FileView = new javax.swing.JButton();
Logs = new javax.swing.JButton();
Logout = new javax.swing.JButton();
jLabel1 = new javax.swing.JLabel();
Logs1 = new javax.swing.JButton();
Logs2 = new javax.swing.JButton();
jScrollPane1 = new javax.swing.JScrollPane();
jTextArea1 = new javax.swing.JTextArea();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jPanel2.setBackground(new java.awt.Color(70, 130, 180));
Home.setBackground(new java.awt.Color(70, 130, 180));
Home.setFont(new java.awt.Font("Lucida Handwriting", 1, 14)); // NOI18N
Home.setText("Home");
Home.setBorderPainted(false);
Home.setFocusCycleRoot(true);
Home.setFocusPainted(false);
Home.addMouseListener(new java.awt.event.MouseAdapter() {
public void mouseClicked(java.awt.event.MouseEvent evt) {
HomeMouseClicked(evt);
}
public void mouseReleased(java.awt.event.MouseEvent evt) {
HomeMouseReleased(evt);
}
});
Home.addChangeListener(new javax.swing.event.ChangeListener() {
public void stateChanged(javax.swing.event.ChangeEvent evt) {
HomeStateChanged(evt);
}
});
Home.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
HomeActionPerformed(evt);
}
});
LiveMonitoring.setBackground(new java.awt.Color(70, 130, 180));
LiveMonitoring.setFont(new java.awt.Font("Lucida Handwriting", 1, 14)); // NOI18N
LiveMonitoring.setText("Live Monitoring");
LiveMonitoring.setBorderPainted(false);
LiveMonitoring.setFocusCycleRoot(true);
LiveMonitoring.setFocusPainted(false);
LiveMonitoring.setFocusable(false);
LiveMonitoring.addMouseListener(new java.awt.event.MouseAdapter() {
public void mouseReleased(java.awt.event.MouseEvent evt) {
LiveMonitoringMouseReleased(evt);
}
});
LiveMonitoring.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
LiveMonitoringActionPerformed(evt);
}
});
FileView.setBackground(new java.awt.Color(70, 130, 180));
FileView.setFont(new java.awt.Font("Lucida Handwriting", 1, 14)); // NOI18N
FileView.setText("File View");
FileView.setBorderPainted(false);
FileView.setFocusCycleRoot(true);
FileView.setFocusPainted(false);
Logs.setBackground(new java.awt.Color(70, 130, 180));
Logs.setFont(new java.awt.Font("Lucida Handwriting", 1, 14)); // NOI18N
Logs.setText("Logs");
Logs.setBorderPainted(false);
Logs.setFocusCycleRoot(true);
Logs.setFocusPainted(false);
Logout.setBackground(new java.awt.Color(70, 130, 180));
Logout.setFont(new java.awt.Font("Lucida Handwriting", 1, 14)); // NOI18N
Logout.setText("Logout");
Logout.setBorderPainted(false);
Logout.setFocusCycleRoot(true);
Logout.setFocusPainted(false);
Logout.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
LogoutActionPerformed(evt);
}
});
jLabel1.setFont(new java.awt.Font("Lucida Handwriting", 1, 24)); // NOI18N
jLabel1.setText(" Ease Serve");
Logs1.setBackground(new java.awt.Color(70, 130, 180));
Logs1.setFont(new java.awt.Font("Lucida Handwriting", 1, 14)); // NOI18N
Logs1.setText("Help");
Logs1.setBorderPainted(false);
Logs1.setFocusCycleRoot(true);
Logs1.setFocusPainted(false);
Logs2.setBackground(new java.awt.Color(70, 130, 180));
Logs2.setFont(new java.awt.Font("Lucida Handwriting", 1, 14)); // NOI18N
Logs2.setText("Contact Us");
Logs2.setBorderPainted(false);
Logs2.setFocusCycleRoot(true);
Logs2.setFocusPainted(false);
jTextArea1.setBackground(new java.awt.Color(173, 216, 230));
jTextArea1.setColumns(20);
jTextArea1.setRows(5);
jScrollPane1.setViewportView(jTextArea1);
javax.swing.GroupLayout jPanel2Layout = new javax.swing.GroupLayout(jPanel2);
jPanel2.setLayout(jPanel2Layout);
jPanel2Layout.setHorizontalGroup(
jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jPanel2Layout.createSequentialGroup()
.addGap(21, 21, 21)
.addComponent(Home, javax.swing.GroupLayout.PREFERRED_SIZE, 106, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(146, 146, 146)
.addComponent(LiveMonitoring, javax.swing.GroupLayout.PREFERRED_SIZE, 185, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(154, 154, 154)
.addComponent(FileView, javax.swing.GroupLayout.PREFERRED_SIZE, 131, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(179, 179, 179)
.addComponent(Logs, javax.swing.GroupLayout.PREFERRED_SIZE, 108, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(189, 189, 189)
.addComponent(Logs1, javax.swing.GroupLayout.PREFERRED_SIZE, 108, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 177, Short.MAX_VALUE)
.addComponent(Logs2)
.addGap(84, 84, 84))
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanel2Layout.createSequentialGroup()
.addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(Logout, javax.swing.GroupLayout.PREFERRED_SIZE, 119, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(39, 39, 39))
.addComponent(jScrollPane1)
.addGroup(jPanel2Layout.createSequentialGroup()
.addGap(549, 549, 549)
.addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 271, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
);
jPanel2Layout.setVerticalGroup(
jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jPanel2Layout.createSequentialGroup()
.addGap(19, 19, 19)
.addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 37, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGroup(jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jPanel2Layout.createSequentialGroup()
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 103, Short.MAX_VALUE)
.addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 439, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(46, 46, 46)
.addComponent(Logout, javax.swing.GroupLayout.PREFERRED_SIZE, 46, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGroup(jPanel2Layout.createSequentialGroup()
.addGap(30, 30, 30)
.addGroup(jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(Home, javax.swing.GroupLayout.PREFERRED_SIZE, 42, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(LiveMonitoring, javax.swing.GroupLayout.PREFERRED_SIZE, 42, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(FileView, javax.swing.GroupLayout.PREFERRED_SIZE, 44, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(Logs, javax.swing.GroupLayout.PREFERRED_SIZE, 42, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(Logs1, javax.swing.GroupLayout.PREFERRED_SIZE, 42, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(Logs2, javax.swing.GroupLayout.PREFERRED_SIZE, 42, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(0, 0, Short.MAX_VALUE))))
);
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addComponent(jPanel2, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(0, 0, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jPanel2, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
);
pack();
}// </editor-fold>
private void HomeActionPerformed(java.awt.event.ActionEvent evt) {
jTextArea1.setText("Clients ID\t\t\tClients Name\t\t\tClients IPAddress\n");
int i=0;
Connection conn=MySqlConnect.ConnectDB();
String Sql="Select * from clients";
try
{
PreparedStatement pst=conn.prepareStatement(Sql);
ResultSet rs=pst.executeQuery();
while(rs.next())
{
String str=rs.getString("hostname");
String str1=rs.getString("ipaddress");
i=i+1;
jTextArea1.append(i+"\t\t\t"+str+"\t\t\t"+str1+"\n");
}
}
catch(Exception e)
{
JOptionPane.showMessageDialog(null,e);
}
LiveMonitoring.setEnabled(false);
}
private void LiveMonitoringActionPerformed(java.awt.event.ActionEvent evt) {
new LiveMOnitoring().setVisible(true);
this.dispose();
}
private void LogoutActionPerformed(java.awt.event.ActionEvent evt) {
new Login().setVisible(true);
this.dispose();
}
private void LiveMonitoringMouseReleased(java.awt.event.MouseEvent evt) {
}
private void HomeMouseReleased(java.awt.event.MouseEvent evt) {
if (jTextArea1.getSelectedText() != null)
{
LiveMonitoring.setEnabled(true);
String s = jTextArea1.getSelectedText();
}
}
private void HomeStateChanged(javax.swing.event.ChangeEvent evt) {
// TODO add your handling code here:
}
private void HomeMouseClicked(java.awt.event.MouseEvent evt) {
if (jTextArea1.getSelectedText() != null)
{
LiveMonitoring.setEnabled(true);
String s = jTextArea1.getSelectedText();
}
}
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(Home.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(Home.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(Home.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(Home.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 Home().setVisible(true);
}
});
}
// Variables declaration - do not modify
public javax.swing.JButton FileView;
public javax.swing.JButton Home;
javax.swing.JButton LiveMonitoring;
public javax.swing.JButton Logout;
public javax.swing.JButton Logs;
public javax.swing.JButton Logs1;
public javax.swing.JButton Logs2;
private javax.swing.JLabel jLabel1;
private javax.swing.JPanel jPanel2;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JTextArea jTextArea1;
// End of variables declaration
}
);
}
但是虽然我选择了ipaddress
但它仍然没有再次启用按钮答案 0 :(得分：0)
只需删除按钮上的ActionListener，直到JTextArea中存在某些内容。你也可以禁用按钮，但它使按钮看起来略微变灰，因此我更喜欢删除ActionListener的方法。
JButton.setEnabled(false);