Java Programming I – Page 2 – Just another Kyoung Shin Park’s Lectures Sites site

June 1, 2020May 31, 2020

Metric Converter

ConverterFrame
MetricConverter (combobox-ItemListener, textfield-KeyListener, button-ActionListener)
-TemperatureConverter
-LengthConverter
-WeightConverter
-VolumeConverter

June 1, 2020May 31, 2020

Temperature Converter

TemperatureConverterFrame

-화씨 (Fahrenheit) 섭씨 (Celsius) 변환기

-JLabel, JTextbox, JButton, JImageIcon, KeyListener, ActionListener

May 31, 2020June 14, 2020

Lab8

Lab8 프로젝트 디렉토리 안에 모든 파일(src/*.java & bin/*.class)와 보고서 (3~4장)를 넣고 JAVA20_Lab8_분반_학번_이름.zip 압축한 후 제출 (Due by 6/11)

Lab8 package & fileIO
java1-lab8
ptable (CSV file)
PersonStreamTest 동영상을 참고하세요.

May 31, 2020May 31, 2020

SliderFrame

SliderFrame
SliderFrame

May 31, 2020May 31, 2020

Key Mouse Motion Listener & Adapter

Key Listener
https://docs.oracle.com/javase/tutorial/uiswing/events/keylistener.html
Mouse Listener
https://docs.oracle.com/javase/tutorial/uiswing/events/mouselistener.html
Mouse Motion Listener
https://docs.oracle.com/javase/tutorial/uiswing/events/mousemotionlistener.html
Key Adapter
https://docs.oracle.com/javase/7/docs/api/java/awt/event/KeyAdapter.html

May 31, 2020May 31, 2020

ChangeListener, KeyListener, ActionListener

SliderFrame (JSlider, JLabel, JTextfield, JButton)

import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import javax.swing.JTextField;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

// SliderFrame shows ChangeListener, KeyListener, ActionListener
public class SliderFrame extends JFrame implements ChangeListener, KeyListener, ActionListener {

    JPanel panel = new JPanel(new BorderLayout());
    JPanel panel1 = new JPanel(new FlowLayout());
    JSlider slider = new JSlider(JSlider.HORIZONTAL, 0, 100, 20);
    JLabel label = new JLabel("Value : ", JLabel.CENTER);
    JTextField textfield = new JTextField(10);
    JButton button = new JButton("Close");

    public SliderFrame(String name) {
        super(name);

        this.add(panel);
        this.panel1.add(label);
        this.panel1.add(textfield);
        this.panel.add(slider, BorderLayout.CENTER);
        this.panel.add(panel1, BorderLayout.NORTH);
        this.panel.add(button, BorderLayout.SOUTH);

        this.slider.addChangeListener(this); // ChangeListener stateChanged
        this.textfield.addKeyListener(this); // KeyListener keyTyped, keyPressed, keyReleased
        this.button.addActionListener(this); // ActionListener actionPerformed

        this.setSize(250, 150);
        this.setVisible(true);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

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

    @Override
    public void stateChanged(ChangeEvent e) {
        JSlider s = (JSlider)e.getSource();
        textfield.setText("" + s.getValue()); 
    }

    @Override
    public void keyTyped(KeyEvent e) { 
    }

    @Override
    public void keyPressed(KeyEvent e) {
    }

    @Override
    public void keyReleased(KeyEvent e) {
        int key = e.getKeyCode();
        if (key == KeyEvent.VK_ENTER) {
            Toolkit.getDefaultToolkit().beep(); 
            System.out.println("ENTER pressed");
            JTextField t = (JTextField) e.getSource();
            int value = Integer.parseUnsignedInt(t.getText());
            slider.setValue(value);
        }
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        JButton b = (JButton)e.getSource();
        if (b == button) {
            this.setVisible(false);
            this.dispose();
        }
    }
}

May 31, 2020May 31, 2020

5 Ways to Implement Event Listener

Slider(JSlider, JLabel)
1. event listener using anonymous class

import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

// SliderFrame1 shows event listener using anonymous class
public class SliderFrame1 extends JFrame {

    JPanel panel = new JPanel(new BorderLayout());
    JSlider slider = new JSlider(JSlider.HORIZONTAL, 0, 100, 20);
    JLabel label = new JLabel("Value : ", JLabel.CENTER);

    public SliderFrame1(String name) {
        super(name);

        this.add(panel);
        this.panel.add(slider, BorderLayout.CENTER);
        this.panel.add(label, BorderLayout.SOUTH);

        // using anonymous class
        this.slider.addChangeListener(new ChangeListener() {
            @Override
            public void stateChanged(ChangeEvent e) {
                JSlider s = (JSlider)e.getSource();
                label.setText("Value : " + s.getValue());
            }
        });

        this.setSize(250, 150);
        this.setVisible(true);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    public static void main(String[] args) {
        new SliderFrame1("SliderTest1");
    }
}

2. event listener using interface implements

import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

// using implements ChangeListener
public class SliderFrame2 extends JFrame implements ChangeListener {

    JPanel panel = new JPanel(new BorderLayout());
    JSlider slider = new JSlider(JSlider.HORIZONTAL, 0, 100, 20);
    JLabel label = new JLabel("Value : ", JLabel.CENTER);

    public SliderFrame2(String name) {
        super(name);

        this.add(panel);
        this.panel.add(slider, BorderLayout.CENTER);
        this.panel.add(label, BorderLayout.SOUTH);

        this.slider.addChangeListener(this); // implements ChangeListener

        this.setSize(250, 150);
        this.setVisible(true);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    public static void main(String[] args) {
        new SliderFrame2("SliderTest2");
    }

    @Override
    public void stateChanged(ChangeEvent e) {
        JSlider s = (JSlider)e.getSource();
        label.setText("Value : " + s.getValue());
    }
}

3. event listener using private inner class

import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

public class SliderFrame3 extends JFrame {

    JPanel panel = new JPanel(new BorderLayout());
    JSlider slider = new JSlider(JSlider.HORIZONTAL, 0, 100, 20);
    JLabel label = new JLabel("Value : ", JLabel.CENTER);

    // using private inner class
    private class SliderChangeListener implements ChangeListener {
        @Override
        public void stateChanged(ChangeEvent e) {
            JSlider s = (JSlider)e.getSource();
            label.setText("Value : " + s.getValue());
        }
    }

    public SliderFrame3(String name) {
        super(name);
        this.add(panel);
        this.panel.add(slider, BorderLayout.CENTER);
        this.panel.add(label, BorderLayout.SOUTH);

        this.slider.addChangeListener(new SliderChangeListener()); // private class

        this.setSize(250, 150);
        this.setVisible(true);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    public static void main(String[] args) {
        new SliderFrame3("SliderTest3");
    }
}

4. event listener using outer class

import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

// using private inner class
class SliderChangeListener implements ChangeListener {
    JLabel label = null;
    public SliderChangeListener(JLabel label) {
        this.label = label;
    }

    @Override
    public void stateChanged(ChangeEvent e) {
        JSlider s = (JSlider)e.getSource();
        label.setText("Value : " + s.getValue());
    }
}

public class SliderFrame4 extends JFrame {

    JPanel panel = new JPanel(new BorderLayout());
    JSlider slider = new JSlider(JSlider.HORIZONTAL, 0, 100, 20);
    JLabel label = new JLabel("Value : ", JLabel.CENTER);

    public SliderFrame4(String name) {
        super(name);
        this.add(panel);
        this.panel.add(slider, BorderLayout.CENTER);
        this.panel.add(label, BorderLayout.SOUTH);

        this.slider.addChangeListener(new SliderChangeListener(this.label)); // outer class

        this.setSize(250, 150);
        this.setVisible(true);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    public static void main(String[] args) {
        new SliderFrame4("SliderTest4");
    }
}

5. event listener using lambda

import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

// SliderFrame5 shows event listener using lambda
public class SliderFrame5 extends JFrame {

    JPanel panel = new JPanel(new BorderLayout());
    JSlider slider = new JSlider(JSlider.HORIZONTAL, 0, 100, 20);
    JLabel label = new JLabel("Value : ", JLabel.CENTER);

    public SliderFrame5(String name) {
        super(name);

        this.add(panel);
        this.panel.add(slider, BorderLayout.CENTER);
        this.panel.add(label, BorderLayout.SOUTH);

        // using lambda
        this.slider.addChangeListener(e -> { // lambda
                JSlider s = (JSlider)e.getSource();
                label.setText("Value : " + s.getValue());
        });

        this.setSize(250, 150);
        this.setVisible(true);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    public static void main(String[] args) {
        new SliderFrame5("SliderTest5");
    }
}

May 31, 2020May 31, 2020