Mega Code Archive
Arc demonstration
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import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Container;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridLayout;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.Arc2D;
import java.awt.geom.Rectangle2D;
import javax.swing.JApplet;
import javax.swing.JComboBox;
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 ArcApp extends JPanel {
MyCanvas canvas;
JComboBox arcBox, fillBox;
JSlider sliderX, sliderY, sliderWidth, sliderHeight, sliderT0, sliderT;
String[] arcLabels = { "Open", "Chord", "Pie" };
int[] arcTypes = { Arc2D.OPEN, Arc2D.CHORD, Arc2D.PIE };
String[] colorLabels = { "Black", "White", "Red", "Green", "Blue" };
Color[] colors = { Color.black, Color.white, Color.red, Color.green,
Color.blue };
public ArcApp() {
super(new BorderLayout());
canvas = new MyCanvas();
int width = 600;
int height = 55;
sliderX = setSlider(0, width, width / 4, width / 2, width / 4);
sliderY = setSlider(0, height, height / 4,
height / 2, height / 4);
sliderWidth = setSlider(0, width, width / 2, width / 2, width / 4);
sliderHeight = setSlider(0, height, height / 2,
height / 2, height / 4);
sliderT0 = setSlider(0, 360, 45, 180, 45);
sliderT = setSlider(0, 360, 135, 180, 45);
JPanel panel1 = new JPanel();
panel1.setLayout(new GridLayout(3, 3));
panel1.add(new JLabel("Location (x,y): ", JLabel.RIGHT));
panel1.add(sliderX);
panel1.add(sliderY);
panel1.add(new JLabel("Size (w,h): ", JLabel.RIGHT));
panel1.add(sliderWidth);
panel1.add(sliderHeight);
panel1.add(new JLabel("Angles (Th0, Th): ", JLabel.RIGHT));
panel1.add(sliderT0);
panel1.add(sliderT);
add(panel1, BorderLayout.NORTH);
arcBox = new JComboBox(arcLabels);
arcBox.setSelectedIndex(0);
arcBox.setAlignmentX(Component.LEFT_ALIGNMENT);
arcBox.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
JComboBox cb = (JComboBox) e.getSource();
canvas.arcType = arcTypes[cb.getSelectedIndex()];
canvas.repaint();
}
});
fillBox = new JComboBox(colorLabels);
fillBox.setSelectedIndex(0);
fillBox.setAlignmentX(Component.LEFT_ALIGNMENT);
fillBox.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
JComboBox cb = (JComboBox) e.getSource();
canvas.fillColor = colors[cb.getSelectedIndex()];
canvas.repaint();
}
});
JPanel panel2 = new JPanel();
panel2.setLayout(new GridLayout(1, 4));
panel2.add(new JLabel("Arc Type: ", JLabel.RIGHT));
panel2.add(arcBox);
panel2.add(new JLabel("Fill Type: ", JLabel.RIGHT));
panel2.add(fillBox);
add(panel2, BorderLayout.SOUTH);
add(canvas,BorderLayout.CENTER);
}
public JSlider setSlider(int min, int max, int init, int mjrTkSp,
int mnrTkSp) {
JSlider slider = new JSlider(JSlider.HORIZONTAL, min, max, init);
slider.setPaintTicks(true);
slider.setMajorTickSpacing(mjrTkSp);
slider.setMinorTickSpacing(mnrTkSp);
slider.setPaintLabels(true);
slider.addChangeListener(new SliderListener());
return slider;
}
class MyCanvas extends JLabel {
Arc2D arc;
double x, y, w, h, startAngle, extent;
Color fillColor;
int arcType;
Rectangle2D boundingRec = null;
public MyCanvas() {
x = 700 / 4;
y = 550 / 4;
w = 600 / 2;
h = 550 / 2;
startAngle = 0;
extent = 135;
arcType = Arc2D.OPEN;
fillColor = Color.black;
setBackground(Color.white);
}
public void paint(Graphics g) {
Graphics2D g2D = (Graphics2D) g;
g2D.setColor(Color.white);
g2D.fill(new Rectangle(getBounds()));
arc = new Arc2D.Double(x, y, w, h, startAngle, extent, arcType);
if (fillColor == Color.white || arcType == Arc2D.OPEN) {
g2D.setColor(Color.black);
g2D.draw(arc);
} else {
g2D.setColor(fillColor);
g2D.fill(arc);
}
boundingRec = arc.getBounds2D();
drawHighlightSquares(g2D, boundingRec);
}
public void drawHighlightSquares(Graphics2D g2D, Rectangle2D r) {
double x = r.getX();
double y = r.getY();
double w = r.getWidth();
double h = r.getHeight();
g2D.setColor(Color.black);
g2D.fill(new Rectangle.Double(x - 3.0, y - 3.0, 6.0, 6.0));
g2D
.fill(new Rectangle.Double(x + w * 0.5 - 3.0, y - 3.0, 6.0,
6.0));
g2D.fill(new Rectangle.Double(x + w - 3.0, y - 3.0, 6.0, 6.0));
g2D
.fill(new Rectangle.Double(x - 3.0, y + h * 0.5 - 3.0, 6.0,
6.0));
g2D.fill(new Rectangle.Double(x + w - 3.0, y + h * 0.5 - 3.0, 6.0,
6.0));
g2D.fill(new Rectangle.Double(x - 3.0, y + h - 3.0, 6.0, 6.0));
g2D.fill(new Rectangle.Double(x + w * 0.5 - 3.0, y + h - 3.0, 6.0,
6.0));
g2D.fill(new Rectangle.Double(x + w - 3.0, y + h - 3.0, 6.0, 6.0));
}
}
class SliderListener implements ChangeListener {
public void stateChanged(ChangeEvent e) {
JSlider slider = (JSlider) e.getSource();
if (slider == sliderX)
canvas.x = slider.getValue();
else if (slider == sliderY)
canvas.y = slider.getValue();
else if (slider == sliderWidth)
canvas.w = slider.getValue();
else if (slider == sliderHeight)
canvas.h = slider.getValue();
else if (slider == sliderT0)
canvas.startAngle = slider.getValue();
else if (slider == sliderT)
canvas.extent = slider.getValue();
canvas.revalidate();
canvas.repaint();
}
}
public static void main (String[] a){
JFrame f = new JFrame();
f.getContentPane().add(new ArcApp());
f.setDefaultCloseOperation(1);
f.setSize(700, 550);
f.setVisible(true);
}
}
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