java 如何更改 JFreeChart 的大小

How do I change a JFreeChart's size

提问by R Doolabh

I've added a JFreeChartto a JPanel(using a BorderLayout), and it's huge. Is there something I can do to make it smaller?

我已将 a 添加JFreeChart到 a JPanel（使用 a BorderLayout），并且它很大。有什么我可以做的让它变小吗？

public void generateChart()
{
    DefaultCategoryDataset dataset = new DefaultCategoryDataset();

    //set the values of the chart
    for(int i=0; i<8; i++)
    {
        dataset.setValue(income_array[i], "Income",
            Double.toString(percent_array[i]));
    }

    JFreeChart chart = ChartFactory.createBarChart(
        "Required Annual Income for a Variety of Interest Rates",
        "Percent", "Income", dataset, PlotOrientation.VERTICAL,
        false,true, false);
    ChartPanel cp = new ChartPanel(chart);

    chart.setBackgroundPaint(Color.white);
    chart.getTitle().setPaint(Color.black); 
    CategoryPlot p = chart.getCategoryPlot(); 
    p.setRangeGridlinePaint(Color.blue); 

    //cp.setMaximumDrawHeight(5);
    //cp.setMaximumDrawWidth(5);
    //cp.setZoomOutFactor(.1);
    JPanel graph = new JPanel();
    graph.add(cp);
    middle.add(graph, BorderLayout.CENTER);
}   

回答by trashgod

When you create your ChartPanel, you have several options that affect the result:

创建 时ChartPanel，您有几个影响结果的选项：

1. Accept the DEFAULT_WIDTHand DEFAULT_HEIGHT: 680 x 420.

2. Specify the preferred widthand heightin the constructor.

3. Invoke setPreferredSize()explicitly if appropriate.

4. Override getPreferredSize()to calculate the size dynamically.

   @Override
   public Dimension getPreferredSize() {
       // given some values of w & h
       return new Dimension(w, h);
   }
   

5. Choose the layoutof the container to which the ChartPanelwill be added. Note that the default layout of JPanelis FlowLayout, while that of JFrameis BorderLayout. As a concrete example, ThermometerDemouses both preferred values in the constructor and a GridLayoutfor the container to allow dynamic resizing.

1. 接受DEFAULT_WIDTH和DEFAULT_HEIGHT：680 x 420。

2. 在构造函数中指定首选width和height。

3. setPreferredSize()如果合适，显式调用。

4. 覆盖getPreferredSize()以动态计算大小。

   @Override
   public Dimension getPreferredSize() {
       // given some values of w & h
       return new Dimension(w, h);
   }
   

5. 选择将添加到的容器的布局ChartPanel。请注意，默认布局JPanel是FlowLayout，而默认布局JFrame是BorderLayout。作为一个具体的例子，ThermometerDemo在构造函数中使用首选值并GridLayout在容器中使用a以允许动态调整大小。

回答by Paul Efford

In addition to answer "4" of @trashgod, I had the same problem and managed to solve it like this: (1) create a custom class which extends JPanel (2) get the size somehow, that you would like to pass to your chart (3) create a method which returns a "ChartPanel" object like this:

除了回答@trashgod 的“4”之外，我也遇到了同样的问题并设法解决了这个问题：（1）创建一个扩展 JPanel 的自定义类（2）以某种方式获取大小，你想传递给你的图表 (3) 创建一个返回“ChartPanel”对象的方法，如下所示：

ChartPanel chart() {
    //... custom code here
    JFreeChart chart = ChartFactory.createPieChart(title, pieDataset, false, false, false );`enter code here`
    // Now: this is the trick to manage setting the size of a chart into a panel!:
    return new ChartPanel(chart) { 
        public Dimension getPreferredSize() {
            return new Dimension(width, height);
        }
    };
}

I prepared a SSCCE to let you know how it works:

我准备了一个 SSCCE 让你知道它是如何工作的：

import java.awt.Dimension;
import java.util.ArrayList;
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 MyPieChart extends JPanel {

    public static void main(String[] args) {
        example1();
        example2();
        example3();
    }

    public static void example1() {
        JPanel panel = new JPanel();
        panel.setBounds(50, 80, 100, 100);
        MyPieChart piePanel = new MyPieChart("Example 1", dataset(), panel);
        panel.add(piePanel);
        JFrame frame = new JFrame();
        frame.setLayout(null); 
        frame.setBounds(10, 10, 200, 300);
        frame.add(panel);
        frame.setVisible(true);
    }

    public static void example2() {
        MyPieChart piePanel = new MyPieChart("Example 2", dataset(), 30, 50, 100, 100);
        JFrame frame = new JFrame();
        frame.setLayout(null); 
        frame.setBounds(210, 10, 200, 300);
        frame.add(piePanel);
        frame.setVisible(true);
    }

    public static void example3() {
        MyPieChart piePanel = new MyPieChart("Example 3", dataset(), 100, 100);
        piePanel.setLocation(0,0);
        JFrame frame = new JFrame();
        frame.setLayout(null); 
        frame.setBounds(410, 10, 200, 300);
        frame.add(piePanel);
        frame.setVisible(true);
    }

    static ArrayList<ArrayList<String>> dataset() {
        ArrayList<ArrayList<String>> dataset = new ArrayList<ArrayList<String>>();
        dataset.add(row( "Tom", "LoggedIn", "Spain" ));
        dataset.add(row( "Jerry", "LoggedOut", "England" ));
        dataset.add(row( "Gooffy", "LoggedOut", "France" ));
        return dataset;
    }

    static ArrayList<String> row(String name, String actualState, String country) {
        ArrayList<String> row = new ArrayList<String>();
        row.add(name); row.add(actualState); row.add(country); 
        return row;
    }

    ArrayList<ArrayList<String>> dataset;
    DefaultPieDataset pieDataset = new DefaultPieDataset(); 
    int width, height, posX, posY;
    int colState = 1;
    String title;
    String LoggedIn = "LoggedIn";
    String LoggedOut = "LoggedOut";

    public MyPieChart(String title, ArrayList<ArrayList<String>> dataset, int...args) {

        if(args.length==2) {
            this.width = args[0];
            this.height = args[1];
            this.setSize(width, height);
        }
        else if(args.length==4) {
            this.posX = args[0];
            this.posY = args[1];
            this.width = args[2];
            this.height = args[3];
            this.setBounds(posX, posY, width, height);
        }
        else {
            System.err.println("Error: wrong number of size/position arguments");
            return;
        }

        this.title = title;
        this.dataset = dataset;
        this.add(chart());
    }

    public MyPieChart(String title, ArrayList<ArrayList<String>> dataset, JPanel panel) {
        this.title = title;
        this.dataset = dataset;
        this.width = panel.getWidth();
        this.height = panel.getHeight();
        this.setBounds(panel.getBounds());
        this.add(chart());
    }

    ChartPanel chart() {

        int totalLoggedIn = 0;
        int totalLoggedOut = 0;

        for(ArrayList<String> user : dataset) {
            if(user.get(colState).equals(LoggedIn)) totalLoggedIn++;
            else totalLoggedOut++;
        }
        pieDataset.clear();
        pieDataset.setValue(LoggedIn +": "+ totalLoggedIn, totalLoggedIn);
        pieDataset.setValue(LoggedOut +": "+ totalLoggedOut, totalLoggedOut);

        JFreeChart chart = ChartFactory.createPieChart(title, pieDataset, false, false, false );

        return new ChartPanel(chart) { // this is the trick to manage setting the size of a chart into a panel!
            public Dimension getPreferredSize() {
                return new Dimension(width, height);
            }
        };
    }
}

I really hope it helps!

我真的希望它有帮助！

回答by StarSweeper

I had a problem with my pie chart being too big with BorderLayout too. I ended up solving my problem by converting the chart to an image instead.

我的饼图在 BorderLayout 上也太大了。我最终通过将图表转换为图像来解决我的问题。

Before

前

After

后

Code

代码

 private PieDataset updateCSFDataSet(){
        DefaultPieDataset dataSet = new DefaultPieDataset();
            dataSet.setValue("Clear(" + clearCount + ")" , clearCount);
            dataSet.setValue("Smoky(" + smokyCount + ")", smokyCount);
            dataSet.setValue("Foggy(" + foggyCount + ")", foggyCount);
            dataSet.setValue("Skipped(" + skipCount + ")", skipCount);
            dataSet.setValue("Unlabeled(" + unlabeledCount + ")", unlabeledCount);
        return dataSet;
    }

    private ImageIcon createChart(String title, PieDataset dataSet){
        JFreeChart chart = ChartFactory.createPieChart(
                title,
                dataSet,
                true,
                false,
                false
        );

        PiePlot plot = (PiePlot) chart.getPlot();
        plot.setLabelFont(new Font("SansSerif", Font.PLAIN, 12));
        plot.setNoDataMessage("No data available");
        plot.setCircular(true);
        plot.setIgnoreZeroValues(true);
        plot.setLabelGap(0.02);

        return new ImageIcon(chart.createBufferedImage(400,300));
    }

回答by Brendan Cutajar

Try setting the size of the Panel your chart is in.

尝试设置图表所在面板的大小。

You might need to set both JPanel middle and ChartPanel cp

您可能需要同时设置 JPanel middle 和 ChartPanel cp