I am working on a pie chart with 4 different elements. I can get the elements to appear in the JFrame but I cannot complete the pie chart circle. These are the elements:
public static class PieChart extends JComponent {
IAPieChart[] pieValue = {new IAPieChart(5, Color.green),
new IAPieChart(4, Color.orange),
new IAPieChart(3, Color.blue),
new IAPieChart(2, Color.red)
};
Now that the elements are instantiated, and loaded into the array, I use this method to paint them:
public void paintComponent(Graphics g) {
drawPie((Graphics2D) g, getBounds(), pieValue);
}
This method puts the elements together on the JFrame but only gives me about 120 degrees of the circle. :
void drawPie(Graphics2D g, Rectangle area, IAPieChart[] pieValue){
double sum = 0.0;
for (int i = 0; i < pieValue.length; i++) {
sum += pieValue[i].arcValue;
}
double endPoint = 0.0D;
int arcStart = 0;
for (int i = 0; i < pieValue.length; i++){
endPoint = (int) (endPoint * 360 / sum);
int radius = (int) (pieValue[i].arcValue * 360/ sum);
g.setColor(pieValue[i].color);
g.fillArc(area.x, area.y, area.width, area.height, arcStart , radius);
radius += pieValue[i].arcValue;
}
}
}
I'm at a loss. I have about 10 weeks expereince with Java so this is mostly trial and error. I am looking for a way to complete the circle. I reduced the values to the lowest point that would make all of the colors show. Anything larger will eliminate one color or the other.
I hope you can help. Here is the full program IAPieChart:
package iapiechart;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import javax.swing.JComponent;
import javax.swing.JFrame;
class IAPieChart{
double arcValue; // passes a value for the calculation of the arc.
Color color; // holds value for color (expressed as an integer
public IAPieChart(double value, Color color){
this.arcValue = value;
this.color = color;
}
public static class PieChart extends JComponent {
IAPieChart[] pieValue = {new IAPieChart(5, Color.green),
new IAPieChart(4, Color.orange),
new IAPieChart(3, Color.blue),
new IAPieChart(2, Color.red)
};
public void paintComponent(Graphics g) {
drawPie((Graphics2D) g, getBounds(), pieValue);
}
void drawPie(Graphics2D g, Rectangle area, IAPieChart[] pieValue){
double sum = 0.0;
for (int i = 0; i < pieValue.length; i++) {
sum += pieValue[i].arcValue;
}
double endPoint = 0.0D;
int arcStart = 0;
for (int i = 0; i < pieValue.length; i++){
endPoint = (int) (endPoint * 360 / sum);
int radius = (int) (pieValue[i].arcValue * 360/ sum);
g.setColor(pieValue[i].color);
g.fillArc(area.x, area.y, area.width, area.height, arcStart , radius);
radius += pieValue[i].arcValue;
}
}
}
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.getContentPane().add(new PieChart());
frame.setSize(300, 300);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(frame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
PiePlotwith source. – Grindelia