JFreeChart - Graphics in Java Swing do not appear on the screen

Question

JFreeChart - Graphics in Java Swing do not appear on the screen

Navigation

#1 by (2 votes)

2

Hello, I'm developing a Java swing application for a university project. Basically it is a program that reads XML files from another application (mobile game) and generates graphical reports from the data (easy thing ...). My question is as follows, I'm using the JFreeChart library which is responsible for creating the graphics, I've taken a basic example to understand how it works and it's pretty simple except it did not work.

I created a JFrame with a JPanel and a button, in the button I put the following code:

DefaultPieDataset dpd = new DefaultPieDataset();
dpd.setValue("Valor 1", 10);
dpd.setValue("Valor 2", 20);
dpd.setValue("Valor 3", 30);
dpd.setValue("Valor 4", 40);

JFreeChart grafico = ChartFactory.createPieChart("Nome do Grafico", dpd, true, true, true);

ChartPanel chartPanel = new ChartPanel(grafico);
primeiroGrafico.add(chartPanel);
primeiroGrafico.validate();

But the chart does not appear inside the panel !?

These are the namespaces :

import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.data.general.DefaultPieDataset;

Thanks in advance!

java swing jfreechart

asked by anonymous 15.03.2015 / 02:30

1 answer

How to obtain the complete zip code through the mobile phone GPS How to get the device's last location

score 2 · Accepted Answer

I tested here with this code and it worked:

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Toolkit;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.data.general.DefaultPieDataset;

public class Grafico {
    public static void main(String[] args) {
        EventQueue.invokeLater(Grafico::run);
    }

    private static void run() {
        // Cria uma tela com uma panel vazia dentro. Usa esta panel para definir
        // o tamanho mínimo e preferencial da janela.
        JFrame frame = new JFrame("Olá, JFreeChart!");
        frame.setResizable(false);
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        JPanel raiz = new JPanel();
        raiz.setLayout(new BorderLayout());
        Dimension tamanho = new Dimension(600, 480);
        raiz.setPreferredSize(tamanho);
        raiz.setMinimumSize(tamanho);
        frame.add(raiz);
        frame.pack();
        Dimension sd = Toolkit.getDefaultToolkit().getScreenSize();
        frame.setLocation((sd.width - frame.getWidth()) / 2, (sd.height - frame.getHeight()) / 2);

        // Cria o painel aonde o gráfico será mostrado.
        JPanel primeiroGrafico = new JPanel();
        Dimension tamanhoArea = new Dimension(600, 450);
        primeiroGrafico.setPreferredSize(tamanhoArea);
        primeiroGrafico.setMinimumSize(tamanhoArea);
        raiz.add(primeiroGrafico, BorderLayout.CENTER);

        // Cria o botão.
        JPanel areaBotoes = new JPanel();
        JButton botao = new JButton("Criar gráfico");
        areaBotoes.add(botao);
        raiz.add(areaBotoes, BorderLayout.SOUTH);

        // Define o que acontece ao clicar no botão.
        botao.addActionListener(e -> {
            DefaultPieDataset dpd = new DefaultPieDataset();
            dpd.setValue("Valor 1", 10);
            dpd.setValue("Valor 2", 20);
            dpd.setValue("Valor 3", 30);
            dpd.setValue("Valor 4", 40);

            JFreeChart grafico = ChartFactory.createPieChart("Nome do Gráfico", dpd, true, true, true);

            ChartPanel chartPanel = new ChartPanel(grafico);
            primeiroGrafico.add(chartPanel);
            primeiroGrafico.validate();
        });

        // Mostra a tela.
        frame.setVisible(true);
    }
}

Here's the result after clicking the button: