Notes

FIG:7.25
##DrawRainbow

import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JPanel;

public class DrawRainbow extends JPanel {

private final static Color VIOLET = new Color(128, 0, 128);
private final static Color INDIGO = new Color(75, 0, 130);
private Color[] colors = {Color.WHITE, Color.WHITE, VIOLET, INDIGO, Color.BLUE,
Color.GREEN, Color.YELLOW, Color.ORANGE, Color.RED};

public DrawRainbow() {
setBackground(Color.WHITE);
}

public void paintComponent(Graphics g) {
super.paintComponent(g);
int radius = 20;

int centerX = getWidth() / 2;
int centerY = getHeight() - 10;

for (int counter = colors.length; counter > 0; counter--) {
g.setColor(colors[counter - 1]);
g.fillArc(centerX - counter * radius,
centerY - counter * radius,
counter * radius * 2,
counter * radius * 2,
0,
180);
}
}
}



FIG:7.26
##DrawRainbowTest

import javax.swing.JFrame;

public class DrawRainbowTest {

public static void main(String[] args) {
DrawRainbow panel = new DrawRainbow();
JFrame application = new JFrame();

application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
application.add(panel);
application.setSize(400, 250);
application.setVisible(true);
}
}


FIG:8.17
##MyLine

import java.awt.Color;
import java.awt.Graphics;

public class MyLine {

private int x1;
private int y1;
private int x2;
private int y2;
private Color color;

public MyLine(int x1, int y1, int x2, int y2, Color color) {
this.x1 = x1;
this.y1 = y1;
this.x2 = x2;
this.y2 = y2;
this.color = color;
}

public void draw(Graphics g) {
g.setColor(color);
g.drawLine(x1, y1, x2, y2);
}
}


FIG:8.18
##DrawPanel

import java.awt.Color;
import java.awt.Graphics;
import java.security.SecureRandom;
import javax.swing.JPanel;

public class DrawPanel extends JPanel {

private SecureRandom randomNumbers = new SecureRandom();
private MyLine[] lines;

public DrawPanel() {
setBackground(Color.WHITE);
lines = new MyLine[5 + randomNumbers.nextInt(5)];

for (int count = 0; count < lines.length; count++) {
int x1 = randomNumbers.nextInt(300);
int y1 = randomNumbers.nextInt(300);
int x2 = randomNumbers.nextInt(300);
int y2 = randomNumbers.nextInt(300);

Color color = new Color(randomNumbers.nextInt(256),
randomNumbers.nextInt(256),
randomNumbers.nextInt(256));

lines[count] = new MyLine(x1, y1, x2, y2, color);
}
}

public void paintComponent(Graphics g) {
super.paintComponent(g);

for (MyLine line : lines) {
line.draw(g);
}
}
}


FIG:8.19
##TestDraw


import javax.swing.JFrame;

public class TestDraw {
public static void main(String[] args) {
DrawPanel panel = new DrawPanel();
JFrame app = new JFrame();

app.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
app.add(panel);
app.setSize(300, 300);
app.setVisible(true);
}
}



FIG:9.13
##LebelDemo


import java.awt.BorderLayout;
import javax.swing.ImageIcon;
import javax.swing.JLabel;
import javax.swing.JFrame;

public class LabelDemo {

public static void main(String[] args) {
JLabel northLabel = new JLabel("North");
ImageIcon labelIcon = new ImageIcon("GUItip.gif");
JLabel centerLabel = new JLabel(labelIcon);
JLabel southLabel = new JLabel(labelIcon);
southLabel.setText("South");
JFrame application = new JFrame();
application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
application.add(northLabel, BorderLayout.NORTH);
application.add(centerLabel, BorderLayout.CENTER);
application.add(southLabel, BorderLayout.SOUTH);

application.setSize(300, 300);
application.setVisible(true);

}
}



FIG:129
##TextFieldFrame

import java.awt.FlowLayout;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.JPasswordField;
import javax.swing.JOptionPane;

public class TextFieldFrame extends JFrame {
private final JTextField textField1;
private final JTextField textField2;
private final JTextField textField3;
private final JPasswordField passwordField;

public TextFieldFrame() {
super("Testing JTextField and JPasswordField");
setLayout(new FlowLayout());

textField1 = new JTextField(10);
add(textField1);

textField2 = new JTextField("Enter text here");
add(textField2);

textField3 = new JTextField("Uneditable text field", 21);
textField3.setEditable(false);
add(textField3);

passwordField = new JPasswordField("Hidden text");
add(passwordField);

TextFieldHandler handler = new TextFieldHandler();
textField1.addActionListener(handler);
textField2.addActionListener(handler);
textField3.addActionListener(handler);
passwordField.addActionListener(handler);
}

private class TextFieldHandler implements ActionListener {
@Override
public void actionPerformed(ActionEvent event) {
String string = "";

if (event.getSource() == textField1)
string = String.format("textField1: %s", event.getActionCommand());
else if (event.getSource() == textField2)
string = String.format("textField2: %s", event.getActionCommand());
else if (event.getSource() == textField3)
string = String.format("textField3: %s", event.getActionCommand());
else if (event.getSource() == passwordField)
string = String.format("passwordField: %s", event.getActionCommand());

JOptionPane.showMessageDialog(null, string);
}
}
}



FIG:12.10
##TextFieldTest

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);
textFieldFrame.setVisible(true);
}
}