public class actionPerformed(ActionEvent e)
    { 
      int count,temp;
      temp=ch.getSelectedIndex();
      if(e.getSource()==btn1)
      {
        ch.select(--temp);
        count=temp;
        content.setText(String.valueOf(add1[temp]+ope2[temp]+add2[temp])+"=");
        radio1.setLabel(String.valueOf(answer[temp][0]));
        radio2.setLabel(String.valueOf(answer[temp][1]));
        radio3.setLabel(String.valueOf(answer[temp][2]));
        radio4.setLabel(String.valueOf(answer[temp][3]));
        if(count==0)
          {
            btn1.setEnabled(false);
          }
          btn2.setEnabled(true);        
        txt1.setText("");      
        check1.setState(false);
        correctLab.setVisible(false);
      }
      if(e.getSource()==btn2)
      { 
        ch.select(++temp);
        count=temp;
        content.setText(String.valueOf(add1[temp]+ope2[temp]+add2[temp])+"=");
        radio1.setLabel(String.valueOf(answer[temp][0]));
        radio2.setLabel(String.valueOf(answer[temp][1]));
        radio3.setLabel(String.valueOf(answer[temp][2]));
        radio4.setLabel(String.valueOf(answer[temp][3]));
       if(count==9)
          {
            btn2.setEnabled(false);
          }
          btn1.setEnabled(true);       
       txt1.setText("");
       check1.setState(false);
       correctLab.setVisible(false);     
      }
      count=temp;      
      if(e.getSource()==txt1)
      {
        String name=txt1.getText();
        if(name.equals(radio1.getLabel()))
         {
           radio1.setState(true);
         }
        if(name.equals(radio2.getLabel()))
         {
          radio2.setState(true);
         }
        if(name.equals(radio3.getLabel()))
         {
          radio3.setState(true);
         }
        if(name.equals(radio4.getLabel()))
         {
          radio4.setState(true);
         }
      }
    }
    public void itemStateChanged(ItemEvent e)
    {
      int count,temp;
      if(e.getItemSelectable()==ch)
       {
        temp=ch.getSelectedIndex();
         count=temp;
         content.setText(String.valueOf(add1[temp]+ope2[temp]+add2[temp])+"=");
         radio1.setLabel(String.valueOf(answer[temp][0]));
         radio2.setLabel(String.valueOf(answer[temp][1]));
         radio3.setLabel(String.valueOf(answer[temp][2]));
         radio4.setLabel(String.valueOf(answer[temp][3]));
         if(count==0)
          {
            btn1.setEnabled(false);
          }
          btn2.setEnabled(true);
         if(count==9)
          {
            btn2.setEnabled(false);
          }
          btn1.setEnabled(true);        
         txt1.setText("");
         check1.setState(false);
         correctLab.setVisible(false); 
       }
      if(e.getItemSelectable()==radio1)
       {
        txt1.setText(radio1.getLabel());
       }
      if(e.getItemSelectable()==radio2)
       {
        txt1.setText(radio2.getLabel());
       }
      if(e.getItemSelectable()==radio3)
       {
        txt1.setText(radio3.getLabel());
       }
      if(e.getItemSelectable()==radio4)
       {
         txt1.setText(radio4.getLabel());
       }
      if(e.getItemSelectable()==check1)
       {
      if(e.getStateChange()==e.SELECTED)
       {
         
         correctLab.setVisible(true);
         temp=ch.getSelectedIndex();
         correctLab.setText("正確答案是："+String.valueOf(correct[temp]));
       }
      else if(e.getStateChange()==e.DESELECTED)
       {
        correctLab.setVisible(false);
       }
      }
    }
  }
  public class xhks120
   {
     public static void main(String args[])
    {
      Myframe fr=new Myframe("");
    }
   }