Question

我正在尝试使用JFreeChart加载大型图表。但是，当缓冲图像高于一定大小时，我的X轴有问题。值在X轴上消失。这可以在图像的第三张图中看到。

我将非常感谢您解决问题的任何帮助

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here

Answer 1

导致此问题的原因是，当图表较大时，ticks（轴上的标记）的数量超过ValueAxis.MAXIMUM_TICK_COUNT。

为了解决此问题，您可以使用ValueAxis.MAXIMUM_TICK_COUNT的增加值重建包，或者您可以编写一个方法，允许您设置最大刻度计数，然后重建包。这将允许您在不同的java文件中设置滴答数量。这可以是ValueAxis.setMaximumTickCount(int ticks)

等方法

取自here

修改
为了实现这一目标，我编辑了org.jfree.chart.axis的两个文件; ValueAxis.java和NumberAxis.java。

对ValueAxis.java的更改。我在课程的底部添加了以下内容。

private int maxTicks = MAXIMUM_TICK_COUNT; public void setMaxTicks(int max) { maxTicks = max; } public int getMaxTicks() { return maxTicks; }

NumberAxis.java的变化在第957行和第1052行，我从
更改了if语句
if (count <= ValueAxis.MAXIMUM_TICK_COUNT) {

到

if (count <= getMaxTicks()) {

最后我使用Apache Ant
重建了它

当图形非常大时，为什么x轴会消失

1 个答案: