12.4简单java计算器

 
import java.awt.FlowLayout;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
 
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.JPasswordField;
import javax.swing.JOptionPane;
 
public class TextFieldFrame extends JFrame 
{
   private JLabel label1;
   private JButton plainJButton; 
   private JTextField textField1;
   private JTextField textField2; 
   private JTextField textField3; 
 
   public TextFieldFrame()
   {
      super( "Testing" );
      setLayout( new FlowLayout() ); 
      
     
      textField1 = new JTextField( 10 ); 
      add( textField1 );
      
     
      label1 = new JLabel( "+" );
      label1.setToolTipText( "This is addition" );
      add( label1 );
 
      
      textField2 = new JTextField( 10 );
      add( textField2 ); 
      
      plainJButton = new JButton( "=" ); 
      add( plainJButton );
      
      textField3 = new JTextField( 10 );
      add( textField3 ); 
 
     
      TextFieldHandler h = new TextFieldHandler();
      /*textField1.addActionListener( h );
      textField2.addActionListener( h );
      textField3.addActionListener( h );*/
      plainJButton.addActionListener( h );
   } 
 
   
   private class TextFieldHandler implements ActionListener 
   {
 
      public void actionPerformed( ActionEvent event )
      {
         if(event.getSource()==plainJButton){
        	 int number1 = Integer.parseInt(textField1.getText());
        	 int number2 = Integer.parseInt(textField2.getText());
        	 int sum = number1 + number2;
        	 String result = String.valueOf(sum);
        	 textField3.setText(result);
        	 //System.out.println(+textField2.getText());
         }
      } 
   } 
} 

 

// Fig. 14.10: TextFieldTest.java
// Testing TextFieldFrame.
import javax.swing.JFrame;
 
public class TextFieldTest
{
   public static void main( String[] args )
   { 
      TextFieldFrame textFieldFrame = new TextFieldFrame(); 
      textFieldFrame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
      textFieldFrame.setSize( 350, 100 ); // set frame size
      textFieldFrame.setVisible( true ); // display frame
   } // end main
} // end class TextFieldTest
 
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