Question

在这里，我想在按下按钮时执行动作，这很容易，但主要问题是要在扩展的JPanel中执行。可能有一个简单的解决方案，如添加动作监听器到该特定按钮并调用actionperformed事件，但我的情况不是这样，我有4个按钮（t1，t2，t3，t4）所有这些按钮将在单个ActionPerfomed中运行事件ae（查看代码段）。稍后您可以看到调用另一个JButtons tr和rf调用actionlistener和actionperformed事件的代码。

为了清楚易懂，您可以浏览一下代码......

 class Tracker extends JPanel
{

public static void main(String[] args) {
    new Tracker();    }

public Tracker()
{

JButton tr=new JButton("TRACKER APPLET");
tr.setBounds(720,170,100,20);

JButton rf=new JButton("REFRESH");
rf.setBounds(200,170,100,20);

boolean tc1=false,tc2=false,tc3=false,tc4=false;

JButton t1=new JButton(" ");
t1.addActionListener(this);
JButton t2=new JButton(" ");
t2.addActionListener(this);
JButton t3=new JButton(" ");
t3.addActionListener(this);
JButton t4=new JButton(" ");
t4.addActionListener(this);


public void actionPerformed(ActionEvent ae)
{
    if(ae.getSource()==t1)
    {
            tc1=true;
    }
    if(ae.getSource()==t2)
    {
            tc2=true;
    }
    if(ae.getSource()==t3)
    {
            tc3=true;
    }
    if(ae.getSource()==t4)
    {
            tc4=true;
    }

}


tr.addActionListener(new ActionListener(){
 public void actionPerformed(ActionEvent e){

    EventQueue.invokeLater(new Runnable() {
        @Override
        public void run() {
            try {
                UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
            } catch (ClassNotFoundException ex){}
            catch(InstantiationException ex){}
            catch(IllegalAccessException ex){}
            catch(UnsupportedLookAndFeelException ex) {}

                //some food here....


                           }
                        });
            }
             });        

    rf.addActionListener(new ActionListener(){
 public void actionPerformed(ActionEvent e){

    EventQueue.invokeLater(new Runnable() {
        @Override
        public void run()
        {
            try {
                UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } 
            catch (ClassNotFoundException ex){}
            catch(InstantiationException ex){}
            catch(IllegalAccessException ex){}
            catch(UnsupportedLookAndFeelException ex) {}
                         //some extra work runs here...
        }
    });
 }
    });
add(tr);
add(rf);
add(t1);
add(t2);
add(t3);
add(t4);
}

我的问题是我无法将ActionListener实现为已经扩展JPanel的主类。我只是想尝试使用Jbuttons ::当按时间顺序按下按钮（t1 | t2 | t3 | t4）和JButtons（tr | rf）时，想要执行单个操作。

提前感谢..

Answer 1

class Tracker extends JPanel implements ActionListener

您的代码包含一些方法...

此代码有效：

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class Tracker extends JPanel implements ActionListener {
   public Tracker() {
      tr.setBounds( 720, 170, 100, 20 );
      tr.addActionListener( this );

      rf.setBounds( 200, 170, 100, 20 );
      rf.addActionListener( this );

      t1.addActionListener( this );
      t2.addActionListener( this );
      t3.addActionListener( this );
      t4.addActionListener( this );
      add(tr);
      add(rf);
      add(t1);
      add(t2);
      add(t3);
      add(t4);
   }

   @Override
   public void actionPerformed( ActionEvent e ) {
      Object src = e.getSource();
      if( src == t1 ) {
         tc1 = true;
      }
      else if( src == t2 ) {
         tc2 = true;
      }
      else if( src == t3 ) {
         tc3 = true;
      }
      else if( src == t4 ) {
         tc4 = true;
      }
      else if( src == tr ) {

      }
      else if( src == rf ) {

      }
   }

   private final JButton tr = new JButton( "TRACKER APPLET" );
   private final JButton rf = new JButton( "REFRESH" );
   private final JButton t1 = new JButton( " " );
   private final JButton t2 = new JButton( " " );
   private final JButton t3 = new JButton( " " );
   private final JButton t4 = new JButton( " " );
   boolean tc1 = false, tc2 = false, tc3 = false, tc4 = false;

   public static void main( String[] args ) {
      JFrame frame = new JFrame( "" );
      frame.add( new Tracker());
      frame.pack();
      frame.setLocationRelativeTo( null );
      frame.setVisible( true );
   }
}

在JPanel中执行ActionListener

1 个答案: