j_slider.java

一个十分好的java基础学习的课件

// ////////////////////////////////////////////////////////
// 
// J_Slider.java
// 

// ////////////////////////////////////////////////////////

import java.awt.*;
import javax.swing.*;
import javax.swing.event.*;

public class J_Slider extends JFrame
{
    private JLabel    m_label  = new JLabel( "0" );
    private JSlider   m_Slider = new JSlider(JSlider.HORIZONTAL, 0, 30, 0);

    public J_Slider( )
    {
        super( "Example of JSlider" );
        Container container = getContentPane( );
        container.setLayout( new FlowLayout( ) );      
        
        container.add( m_label );
        container.add( m_Slider );
        m_Slider.addChangeListener(new ChangeListener( ) // Register event handler
            {// anonymous inner class to handle events
                public void stateChanged(ChangeEvent e)
                {
                    int i= ((JSlider)e.getSource( )).getValue( );
                    m_label.setText( new Integer(i).toString( ) );
                } // End of method: stateChanged
            } // End of anonymous inner class (ChangeListener)
        ); // End of invoking addChangeListener

        setSize( 220, 80 );
        setVisible( true );
    } // End of constructor: J_Slider( )
    
    public static void main( String args[] )
    { 
        J_Slider app = new J_Slider( );
        app.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE );
    } // End of method: main

} // End of class: J_Slider