How do I create a pie chart in Java

问题

I want to create a pie chart that displays percentages. How do I create a pie chart using JFrame in Java?

This is what I have so far:

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

public class PieChart extends JFrame{


private int Midterm;
private int Quizzes;
private int Projects;
private int Final;

public PieChart(){
    setPercentage();

}
private void setPercentage() {
    // TODO Auto-generated method stub

}
//construct a pie chart with percentages
public PieChart(int Midterm, int Quizzes, int Final, int Projects){
this.Midterm = Midterm;
this.Quizzes = Quizzes;
this.Final = Final;
this.Projects = Projects;
}
//return midterm
public int getMidterm(){
    return Midterm;

}
//public void setMidterm(int Midterm){
    //this.Midterm = Midterm;
    //repaint();

//}
//return Quizzes
public int getQuizzes(){
    return Quizzes;

}
public int Final(){
    return Final;
}
public int Projects(){
    return Projects;

}
//draw the circle
protected void paintComponent(Graphics g){
    super.paintComponents(g);

}
//initialize circle parameters
int circleRadius = 
    (int)(Math.min(getWidth(),getHeight())* 0.4);
int xCenter= getWidth()/2;
int yCenter = getHeight()/2;

}

回答1:

to draw pie chart you should use fillArc(x,y,width,height,starting angle,arc angle)

draw different arcs related to each other (1st i.e left side arc must be same as right side of previous arc)

you have to make your own logic for setting starting angle...

suppose u have total 12 products and u want to draw pie-chart for them (sale)

total of 12 product's sale = 1200

individual product sale a = 120, b = 0, c = 500,.....

angle for individual product a = (120*360)/1200 b = 0 c = (500*360)/

and then set relative arc angle

i think so this will give u your pie chart

回答2:

Do you have to develop it on your own? Or can you use an open source API? Maybe JFreeChart has something you can use.

回答3:

In the paintComponent method, a Graphics object is passed in. With this, you can use fillArc to draw the various slices and drawString to label them.

Also, I'd suggest that you don't draw directly on the JFrame, but instead do so on a JComponent that you then add to a JFrame.

来源：https://stackoverflow.com/questions/3773107/how-do-i-create-a-pie-chart-in-java

标签

java

user-interface

pie-chart