java 折线_用Java绘制简单的折线图

只是对气垫船充满鳗鱼的解决方案的补充：

我重新设计了他的代码，对其进行了一些微调，添加了网格，轴标签，现在Y轴从当前的最小值变为最大值。我计划添加一些吸气剂/吸气剂，但我不需要它们，可以根据需要添加它们。

这是Gist链接，我还将粘贴以下代码：Gist上的GraphPanel

import java.awt.BasicStroke;

import java.awt.Color;

import java.awt.Dimension;

import java.awt.FontMetrics;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.Point;

import java.awt.RenderingHints;

import java.awt.Stroke;

import java.util.ArrayList;

import java.util.List;

import java.util.Random;

import javax.swing.JFrame;

import javax.swing.JPanel;

import javax.swing.SwingUtilities;

public class GraphPanel extends JPanel {

private int width = 800;

private int heigth = 400;

private int padding = 25;

private int labelPadding = 25;

private Color lineColor = new Color(44, 102, 230, 180);

private Color pointColor = new Color(100, 100, 100, 180);

private Color gridColor = new Color(200, 200, 200, 200);

private static final Stroke GRAPH_STROKE = new BasicStroke(2f);

private int pointWidth = 4;

private int numberYDivisions = 10;

private List scores;

public GraphPanel(List scores) {

this.scores = scores;

}

@Override

protected void paintComponent(Graphics g) {

super.paintComponent(g);

Graphics2D g2 = (Graphics2D) g;

g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);

double xScale = ((double) getWidth() - (2 * padding) - labelPadding) / (scores.size() - 1);

double yScale = ((double) getHeight() - 2 * padding - labelPadding) / (getMaxScore() - getMinScore());

List graphPoints = new ArrayList<>();

for (int i = 0; i < scores.size(); i++) {

int x1 = (int) (i * xScale + padding + labelPadding);

int y1 = (int) ((getMaxScore() - scores.get(i)) * yScale + padding);

graphPoints.add(new Point(x1, y1));

}

// draw white background

g2.setColor(Color.WHITE);

g2.fillRect(padding + labelPadding, padding, getWidth() - (2 * padding) - labelPadding, getHeight() - 2 * padding - labelPadding);

g2.setColor(Color.BLACK);

// create hatch marks and grid lines for y axis.

for (int i = 0; i < numberYDivisions + 1; i++) {

int x0 = padding + labelPadding;

int x1 = pointWidth + padding + labelPadding;

int y0 = getHeight() - ((i * (getHeight() - padding * 2 - labelPadding)) / numberYDivisions + padding + labelPadding);

int y1 = y0;

if (scores.size() > 0) {

g2.setColor(gridColor);

g2.drawLine(padding + labelPadding + 1 + pointWidth, y0, getWidth() - padding, y1);

g2.setColor(Color.BLACK);

String yLabel = ((int) ((getMinScore() + (getMaxScore() - getMinScore()) * ((i * 1.0) / numberYDivisions)) * 100)) / 100.0 + "";

FontMetrics metrics = g2.getFontMetrics();

int labelWidth = metrics.stringWidth(yLabel);

g2.drawString(yLabel, x0 - labelWidth - 5, y0 + (metrics.getHeight() / 2) - 3);

}

g2.drawLine(x0, y0, x1, y1);

}

// and for x axis

for (int i = 0; i < scores.size(); i++) {

if (scores.size() > 1) {

int x0 = i * (getWidth() - padding * 2 - labelPadding) / (scores.size() - 1) + padding + labelPadding;

int x1 = x0;

int y0 = getHeight() - padding - labelPadding;

int y1 = y0 - pointWidth;

if ((i % ((int) ((scores.size() / 20.0)) + 1)) == 0) {

g2.setColor(gridColor);

g2.drawLine(x0, getHeight() - padding - labelPadding - 1 - pointWidth, x1, padding);

g2.setColor(Color.BLACK);

String xLabel = i + "";

FontMetrics metrics = g2.getFontMetrics();

int labelWidth = metrics.stringWidth(xLabel);

g2.drawString(xLabel, x0 - labelWidth / 2, y0 + metrics.getHeight() + 3);

}

g2.drawLine(x0, y0, x1, y1);

}

}

// create x and y axes

g2.drawLine(padding + labelPadding, getHeight() - padding - labelPadding, padding + labelPadding, padding);

g2.drawLine(padding + labelPadding, getHeight() - padding - labelPadding, getWidth() - padding, getHeight() - padding - labelPadding);

Stroke oldStroke = g2.getStroke();

g2.setColor(lineColor);

g2.setStroke(GRAPH_STROKE);

for (int i = 0; i < graphPoints.size() - 1; i++) {

int x1 = graphPoints.get(i).x;

int y1 = graphPoints.get(i).y;

int x2 = graphPoints.get(i + 1).x;

int y2 = graphPoints.get(i + 1).y;

g2.drawLine(x1, y1, x2, y2);

}

g2.setStroke(oldStroke);

g2.setColor(pointColor);

for (int i = 0; i < graphPoints.size(); i++) {

int x = graphPoints.get(i).x - pointWidth / 2;

int y = graphPoints.get(i).y - pointWidth / 2;

int ovalW = pointWidth;

int ovalH = pointWidth;

g2.fillOval(x, y, ovalW, ovalH);

}

}

// @Override

// public Dimension getPreferredSize() {

// return new Dimension(width, heigth);

// }

private double getMinScore() {

double minScore = Double.MAX_VALUE;

for (Double score : scores) {

minScore = Math.min(minScore, score);

}

return minScore;

}

private double getMaxScore() {

double maxScore = Double.MIN_VALUE;

for (Double score : scores) {

maxScore = Math.max(maxScore, score);

}

return maxScore;

}

public void setScores(List scores) {

this.scores = scores;

invalidate();

this.repaint();

}

public List getScores() {

return scores;

}

private static void createAndShowGui() {

List scores = new ArrayList<>();

Random random = new Random();

int maxDataPoints = 40;

int maxScore = 10;

for (int i = 0; i < maxDataPoints; i++) {

scores.add((double) random.nextDouble() * maxScore);

//scores.add((double) i);

}

GraphPanel mainPanel = new GraphPanel(scores);

mainPanel.setPreferredSize(new Dimension(800, 600));

JFrame frame = new JFrame("DrawGraph");

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.getContentPane().add(mainPanel);

frame.pack();

frame.setLocationRelativeTo(null);

frame.setVisible(true);

}

public static void main(String[] args) {

SwingUtilities.invokeLater(new Runnable() {

public void run() {

createAndShowGui();

}

});

}

}