JButton 대신 JComboBox를 사용하여 JTable 채우기

Question

저는 자바 초보자입니다. JButton을 사용하여 데이터베이스의 데이터로 채워진 JTable을 보게되어 기쁩니다. 나는 학생 세 테이블을 가지고, 교사, & 감독은입니다. 3 개의 JButton (각 테이블마다 1 개)을 사용하여 JTable의 필드를 보는 데 모든 것이 잘 작동합니다. 그러나 다른 JButton을 클릭 할 때마다 JTable은 지워지지 않고 대신 JTable의 기존 정보에 데이터를 추가합니다.

이제 3 JButton을 JComboBox로 대체하여 선택하는 옵션이 테이블 이름이고 해당 내용을 JTable에 표시하려고합니다. 나는 이것을 어떻게하는지에 대해 전혀 모른다. 이 정보로 도움을 주시고 모든 의견을 정말로 기분 좋게 보내 주시기 바랍니다.

감사합니다.

다음은 내가 사용하는 코드입니다. 나는 또한 몇몇 자막을 포함했다.

import java.sql.*; 
import java.util.logging.Level; 
import java.util.logging.Logger; 
import javax.swing.DefaultComboBoxModel; 
import javax.swing.table.DefaultTableModel; 

public class tests extends javax.swing.JFrame { 

/** 
* Creates new form tests 
*/ 
public tests() { 
    initComponents(); 
} 

@SuppressWarnings("unchecked") 
// <editor-fold defaultstate="collapsed" desc="Generated Code"> 
private void initComponents() { 

    jScrollPane1 = new javax.swing.JScrollPane(); 
    dataTable = new javax.swing.JTable(); 
    students = new javax.swing.JButton(); 
    teachers = new javax.swing.JButton(); 
    directors = new javax.swing.JButton(); 

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); 

    dataTable.setModel(new javax.swing.table.DefaultTableModel(
     new Object [][] { 

     }, 
     new String [] { 
      "ID", "Name", "Surname", "Age" 
     } 
    )); 
    jScrollPane1.setViewportView(dataTable); 

    students.setText("Students"); 
    students.addActionListener(new java.awt.event.ActionListener() { 
     public void actionPerformed(java.awt.event.ActionEvent evt) { 
      studentsActionPerformed(evt); 
     } 
    }); 

    teachers.setText("Teachers"); 
    teachers.addActionListener(new java.awt.event.ActionListener() { 
     public void actionPerformed(java.awt.event.ActionEvent evt) { 
      teachersActionPerformed(evt); 
     } 
    }); 

    directors.setText("Directors"); 
    directors.addActionListener(new java.awt.event.ActionListener() { 
     public void actionPerformed(java.awt.event.ActionEvent evt) { 
      directorsActionPerformed(evt); 
     } 
    }); 

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); 
    getContentPane().setLayout(layout); 
    layout.setHorizontalGroup(
     layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
     .addGroup(layout.createSequentialGroup() 
      .addContainerGap() 
      .addComponent(students) 
      .addGap(57, 57, 57) 
      .addComponent(teachers) 
      .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 66, Short.MAX_VALUE) 
      .addComponent(directors) 
      .addGap(40, 40, 40)) 
     .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 0, Short.MAX_VALUE) 
    ); 
    layout.setVerticalGroup(
     layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
     .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup() 
      .addContainerGap() 
      .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) 
       .addComponent(students) 
       .addComponent(teachers) 
       .addComponent(directors)) 
      .addGap(18, 18, 18) 
      .addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 274, Short.MAX_VALUE)) 
    ); 

    pack(); 
}// </editor-fold> 

private void studentsActionPerformed(java.awt.event.ActionEvent evt) { 
    DefaultTableModel model = (DefaultTableModel) dataTable.getModel(); 
    String sql = "select * from students"; 
    try { 
     try { 
      Class.forName("com.mysql.jdbc.Driver"); 
     } catch (ClassNotFoundException ex) { 
      Logger.getLogger(tests.class.getName()).log(Level.SEVERE, null, ex); 
     } 
     Connection connect = (Connection) DriverManager.getConnection("jdbc:mysql://localhost:3306/datavisibility","root",""); 
     Statement statmnt = connect.createStatement(); 
     ResultSet rslt = statmnt.executeQuery(sql); 
     while(rslt.next()){ 
      String id = rslt.getString("ID"); 
      String name = rslt.getString("Name"); 
      String surname = rslt.getString("Surname"); 
      String age = rslt.getString("Age"); 
      model.addRow(new Object[]{id,name,surname,age}); 
     } 
    } catch(SQLException e){ 
     e.printStackTrace(); 
    } 
} 

private void teachersActionPerformed(java.awt.event.ActionEvent evt) { 
    DefaultTableModel model = (DefaultTableModel) dataTable.getModel(); 
    String sql = "select * from teachers"; 
    try { 
     try { 
      Class.forName("com.mysql.jdbc.Driver"); 
     } catch (ClassNotFoundException ex) { 
      Logger.getLogger(tests.class.getName()).log(Level.SEVERE, null, ex); 
     } 
     Connection connect = (Connection) DriverManager.getConnection("jdbc:mysql://localhost:3306/datavisibility","root",""); 
     Statement statmnt = connect.createStatement(); 
     ResultSet rslt = statmnt.executeQuery(sql); 
     while(rslt.next()){ 
      String id = rslt.getString("ID"); 
      String name = rslt.getString("Name"); 
      String surname = rslt.getString("Surname"); 
      String age = rslt.getString("Age"); 
      model.addRow(new Object[]{id,name,surname,age}); 
     } 
    } catch(SQLException e){ 
     e.printStackTrace(); 
    } 
} 

private void directorsActionPerformed(java.awt.event.ActionEvent evt) { 
    DefaultTableModel model = (DefaultTableModel) dataTable.getModel(); 
    String sql = "select * from directors"; 
    try { 
     try { 
      Class.forName("com.mysql.jdbc.Driver"); 
     } catch (ClassNotFoundException ex) { 
      Logger.getLogger(tests.class.getName()).log(Level.SEVERE, null, ex); 
     } 
     Connection connect = (Connection) DriverManager.getConnection("jdbc:mysql://localhost:3306/datavisibility","root",""); 
     Statement statmnt = connect.createStatement(); 
     ResultSet rslt = statmnt.executeQuery(sql); 
     while(rslt.next()){ 
      String id = rslt.getString("ID"); 
      String name = rslt.getString("Name"); 
      String surname = rslt.getString("Surname"); 
      String age = rslt.getString("Age"); 
      model.addRow(new Object[]{id,name,surname,age}); 
     } 
    } catch(SQLException e){ 
     e.printStackTrace(); 
    } 
} 

/** 
* @param args the command line arguments 
*/ 
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(tests.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); 
    } catch (InstantiationException ex) { 
     java.util.logging.Logger.getLogger(tests.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); 
    } catch (IllegalAccessException ex) { 
     java.util.logging.Logger.getLogger(tests.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); 
    } catch (javax.swing.UnsupportedLookAndFeelException ex) { 
     java.util.logging.Logger.getLogger(tests.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 tests().setVisible(true); 
     } 
    }); 
} 
// Variables declaration - do not modify 
private javax.swing.JTable dataTable; 
private javax.swing.JButton directors; 
private javax.swing.JScrollPane jScrollPane1; 
private javax.swing.JButton students; 
private javax.swing.JButton teachers; 
// End of variables declaration 
} 

캡션을 사전에 here.

감사를 참조하십시오.

Answer 1

그냥 대신이 같은 JButton의의 JComboBox에 추가 도움이 필요하면 코드를 게시

ActionListener actionListener = new ActionListener() { 
    public void actionPerformed(ActionEvent actionEvent) { 
    //System.out.println("Selected: " + cb.getSelectedItem()); 
    if(cb.getSelectedItem() == "student"){ 

     //Perform the action for student 

    } 

     //Repeat this for all items 

    } 
}; 
cb.addActionListener(actionListener); 

이것은 당신이 기대하는 것을 할 것입니다 ....

Answer 2

JCombobox 용 ActionListener를 추가하기 만하면됩니다. actionListener에서 getSelectedItem()에 의해 반환 된 값을 기반으로 테이블의 데이터를 변경합니다.

,

String[] items = {"students", "teachers", "directors"}; 
JComboBox cb = new JComboBox(items); 
cb.setEditable(true); 

이 같은 콤보하는 리스너 클래스를 추가, 그것을 쓰는 시도하고 당신이