为什么图形很大时x轴会消失 [英] Why does the x axis disappear when the graph very big

问题描述

我正在尝试使用JFreeChart加载大型图形.但是，当缓冲的图像超过特定大小时，X轴存在问题.值在X轴上消失.可以在图片的第三张图中看到.

I am trying to load large graphs using JFreeChart. However, I have a problem with the X axis when the buffered image is above a certain size. The values disappear on the X axis. This can be seen in the third graph on the image.

希望能为您解决问题提供帮助

I would appreciate any help in fixing the problem

import java.awt.Color;
import java.awt.image.BufferedImage;
import java.util.ArrayList;

import org.jfree.chart.ChartFactory;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.XYPlot;
import org.jfree.data.xy.XYSeries;
import org.jfree.data.xy.XYSeriesCollection;

import javafx.application.Application;
import javafx.concurrent.Task;
import javafx.embed.swing.SwingFXUtils;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.ScrollPane;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class Program2 extends Application {
    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage primaryStage) {
        try {
            StackPane p = new StackPane();
            primaryStage.setTitle("Chart Application");
            Label loader = new Label("Loading...");
            loader.setGraphic(new ImageView(new Image("https://media.giphy.com/media/FmcNeI0PnsAKs/giphy.gif")));
            loader.setFont(new javafx.scene.text.Font(35));
            p.setStyle("-fx-background: #FFFFFF;");
            p.getChildren().add(loader);
            StackPane.setAlignment(loader, Pos.CENTER);

            Scene scene = new Scene(p, 600, 600);
            primaryStage.setScene(scene);
            primaryStage.setMaximized(true);

            Task<ArrayList<ImageView>> loadInitial = new Task<ArrayList<ImageView>>() {
                @Override
                public ArrayList<ImageView> call() {
                    ArrayList<ImageView> images = new ArrayList<ImageView>();
                    XYSeries data = new XYSeries(1);

                    for(int j = 0; j <= 100; j += 2) {
                        data.add(j, -0.2);
                        data.add(j, 1);
                        data.add(j + 1, 1);
                        data.add(j + 1, -0.2);
                    }

                    XYSeriesCollection dataset = new XYSeriesCollection(data);

                    JFreeChart chart = ChartFactory.createXYAreaChart("", "", "", dataset, PlotOrientation.VERTICAL, false, false, false);
                    chart.setBackgroundPaint(Color.WHITE);
                    chart.setBorderVisible(false);
                    chart.setAntiAlias(true);

                    XYPlot plot = (XYPlot) chart.getPlot();

                    ValueAxis range = plot.getRangeAxis();
                    range.setLowerMargin(0);
                    range.setUpperMargin(0);
                    range.setVisible(false);

                    ValueAxis domainAxis = plot.getDomainAxis();
                    domainAxis.setLowerMargin(0);
                    domainAxis.setUpperMargin(0);

                    BufferedImage capture = chart.createBufferedImage(1000, 50);
                    ImageView imageView = new ImageView();
                    Image chartImg = SwingFXUtils.toFXImage(capture, null);
                    imageView.setImage(chartImg);

                    images.add(imageView);

                    BufferedImage capture2 = chart.createBufferedImage(10000, 50);
                    ImageView imageView2 = new ImageView();
                    Image chartImg2 = SwingFXUtils.toFXImage(capture2, null);
                    imageView2.setImage(chartImg2);

                    images.add(imageView2);

                    BufferedImage capture3 = chart.createBufferedImage(100000, 50);
                    ImageView imageView3 = new ImageView();
                    Image chartImg3 = SwingFXUtils.toFXImage(capture3, null);
                    imageView3.setImage(chartImg3);

                    images.add(imageView3);

                    return images;
                }
            };

            loadInitial.setOnSucceeded(e -> {
                VBox images = new VBox();
                ArrayList<ImageView> result = loadInitial.getValue();
                for(ImageView image : result) {
                    images.getChildren().add(image);
                }

                ScrollPane scrollPane = new ScrollPane(images);
                scrollPane.setStyle("-fx-background: #FFFFFF;");

                scene.setRoot(scrollPane);
            });

            new Thread(loadInitial).start();

            primaryStage.show();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

注意
我还发布了推荐答案

之所以引起此问题，是因为图形很大时，ticks(轴上的标记)的数量超过了ValueAxis.MAXIMUM_TICK_COUNT.

This problem is caused because the number of ticks (markers on the axis) exceeds the ValueAxis.MAXIMUM_TICK_COUNT when a graph is that large.

为了解决此问题，您可以使用增加的ValueAxis.MAXIMUM_TICK_COUNT值来重建程序包，或者可以编写一种方法来设置最大刻度数，然后重建程序包.这将允许您设置其他Java文件中的刻度数.这可能是诸如ValueAxis.setMaximumTickCount(int ticks)

In order to fix this problem, you can rebuild the package with an increased value for ValueAxis.MAXIMUM_TICK_COUNT or you could write a method that will allow you to set the maximum tick count and then rebuild the pack. This will allow you to set the amount of ticks in a different java file. This could be a method such as ValueAxis.setMaximumTickCount(int ticks)

来自此处

修改
为了实现这一点，我从org.jfree.chart.axis编辑了两个文件； ValueAxis.java和NumberAxis.java.

Edit
In order to achieve this, I edited two files from org.jfree.chart.axis; ValueAxis.java and NumberAxis.java.

更改为ValueAxis.java.我将以下内容添加到了课程的底部.

Changes to ValueAxis.java. I added the following to the bottom of the class.

private int maxTicks = MAXIMUM_TICK_COUNT;

public void setMaxTicks(int max) {
    maxTicks = max;
}

public int getMaxTicks() {
    return maxTicks;
}

更改为NumberAxis.java.
在957行和1052行上，我将if语句更改为

Changes to NumberAxis.java.
On the line 957 and line 1052 I changed an if statement from

if (count <= ValueAxis.MAXIMUM_TICK_COUNT) {

到

if (count <= getMaxTicks()) {

最后，我使用 Apache Ant

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