Custom Java Swing Meter Control
- by Tyler
I'm trying to make a custom swing control that is a meter.
The arrow will move up and down. Here is my current code, but I feel I've done it wrong.
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.LinearGradientPaint;
import java.awt.Polygon;
import java.awt.Stroke;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class meter extends JFrame {
Stroke drawingStroke = new BasicStroke(2);
Rectangle2D rect = new Rectangle2D.Double(105, 50, 40, 200);
Double meterPercent = new Double(0.57);
public meter() {
setTitle("Meter");
setLayout(null);
setSize(300, 300);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLocationRelativeTo(null);
setVisible(true);
}
public void paint(Graphics g) {
// Paint Meter
Graphics2D g1 = (Graphics2D) g;
g1.setStroke(drawingStroke);
g1.draw(rect);
// Set Meter Colors
Point2D start = new Point2D.Float(0, 0);
Point2D end = new Point2D.Float(0, this.getHeight());
float[] dist = { 0.1f, 0.5f, 0.9f };
Color[] colors = { Color.green, Color.yellow, Color.red };
LinearGradientPaint p = new LinearGradientPaint(start, end, dist,
colors);
g1.setPaint(p);
g1.fill(rect);
// Make a triangle - Arrow on Meter
int[] x = new int[3];
int[] y = new int[3];
int n; // count of points
// Set Points for Arrow
Integer meterArrowHypotenuse = (int) rect.getX();
Integer meterArrowTip = (int) rect.getY()
+ (int) (rect.getHeight() * (1 - meterPercent));
x[0] = meterArrowHypotenuse - 25;
x[1] = meterArrowHypotenuse - 25;
x[2] = meterArrowHypotenuse - 5;
y[0] = meterArrowTip - 20; // Top Left
y[1] = meterArrowTip + 20; // Bottom Left
y[2] = meterArrowTip; // Tip of Arrow
n = 3; // Number of points, 3 because its a triangle
// Draw Arrow Border
Polygon myTriShadow = new Polygon(x, y, n); // a triangle
g1.setPaint(Color.black);
g1.fill(myTriShadow);
// Set Points for Arrow Board
x[0] = x[0] + 1;
x[1] = x[1] + 1;
x[2] = x[2] - 2;
y[0] = y[0] + 3;
y[1] = y[1] - 3;
y[2] = y[2];
Robot robot = new Robot();
Color colorMeter = robot.getPixelColor(x[2]+10, y[2]);
// Draw Arrow
Polygon myTri = new Polygon(x, y, n); // a triangle
Color colr = new Color(colorMeter.getRed(), colorMeter.getGreen(), colorMeter.getBlue());
g1.setPaint(colr);
g1.fill(myTri);
}
public static void main(String[] args) {
new meter();
}
}
Thanks for looking.
