by the code below, the graph is made and at the end added to a jpanel in another class which has a bar to show the long graph (usually over 3000 width):
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 javax.swing.JPanel;
public class Gf extends JPanel {
private int padding = 0;
private int labelPadding = 0;
private Color pointColor = new Color(0, 100, 100);
private int pointWidth = 1;
private int numberYDivisions = 2;
private List<Double> scores;
public Gf(List<Double> 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) / 2000;
List<Point> 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));
}
g2.setColor(Color.BLACK);
g2.fillRect(padding + labelPadding, padding, getWidth() - (2 * padding) - labelPadding, getHeight() - 2 * padding - labelPadding);
g2.setColor(Color.BLACK);
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) {
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);
}
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) {
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);
}
}
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.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);
}
}
private double getMinScore() {
double minScore = -1000; return minScore;}
private double getMaxScore() {
double maxScore = 1000; return maxScore;}
public void setScores(List<Double> scores) {
this.scores = scores;
invalidate();
this.repaint();
}
public List<Double> getScores() {
return scores;
}
public static void createAndShowGui() {
List<Double> scores = new ArrayList<>();
short[] x=mainclass.data;
for (int i = 0; i < x.length; i++) {
scores.add((double)x[i]);}
Gf mainPanel = new Gf(scores);
int width=mainclass.withofgraph;
mainPanel.setPreferredSize(new Dimension(width, 276));
mainclass.p.add(mainPanel);
mainclass.f.revalidate(); mainclass.f.repaint();
}
}
but the problem is the bar is slow to be usable when scrolling to check all the graph and that's specially when graph contains many points and the device is slower.
how to save the made graph at the end of the code to as image so that the image gets added to the jpanel so that solve the slowness problem.
What I have tried:
when increasing the width like 10 times wider, it works fine even on slower devices but its then too long for its purpose.