如何更改JFreeChart的大小

Question

我已經將一個JFreeChart添加到JPanel （使用BorderLayout ），並且它是巨大的 。 有什么我可以做的讓它變小嗎？

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);
}   

Answer 1

創建ChartPanel ，有幾個選項會影響結果：

1. 接受DEFAULT_WIDTH和DEFAULT_HEIGHT ：680 x 420。

2. 在構造函數中指定首選width和height 。

3. 如果合適，則顯式調用setPreferredSize() 。

4. 重寫getPreferredSize()以動態計算大小。

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

5. 選擇要添加ChartPanel的容器的布局 。 請注意， JPanel的默認布局是FlowLayout ，而JFrame的默認布局是BorderLayout 。 作為一個具體示例， ThermometerDemo使用構造函數中的首選值和容器的GridLayout來允許動態調整大小。

Answer 2

除了回答@trashgod的“4”之外，我遇到了同樣的問題並設法解決了這個問題：（1）創建一個自定義類，擴展JPanel（2）以某種方式得到大小，你想要傳遞給你chart（3）創建一個返回“ChartPanel”對象的方法，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);
        }
    };
}

我准備了一個SSCCE讓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);
            }
        };
    }
}

我真的希望它有所幫助！

Answer 3

我的餅圖對BorderLayout來說太大了我的問題。 我最終通過將圖表轉換為圖像來解決我的問題。

之前

后

碼

 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));
    }

Answer 4

嘗試設置圖表所在面板的大小。

您可能需要同時設置JPanel middle和ChartPanel cp

Answer 5

http://www.jfree.org/phpBB2/viewtopic.php?f=3&t=18631

http://www.jfree.org/forum/viewtopic.php?f=3&t=109615

http://www.jfree.org/phpBB2/viewtopic.php?f=3&t=31582