我正在使用 Java 中的 OpenStreetMap 和 JMapViewer。 我可以使用JMapViewer绘制多边形和矩形,但是如何绘制折线?
谢谢。
最佳答案
您可以创建自己的折线实现。下面是基于现有 MapPolygonImpl
的示例。这很hacky,但是JMapViewer
中似乎没有方法来添加行。
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.geom.Path2D;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
import org.openstreetmap.gui.jmapviewer.Coordinate;
import org.openstreetmap.gui.jmapviewer.JMapViewer;
import org.openstreetmap.gui.jmapviewer.MapPolygonImpl;
import org.openstreetmap.gui.jmapviewer.interfaces.ICoordinate;
public class TestMap {
public static class MapPolyLine extends MapPolygonImpl {
public MapPolyLine(List<? extends ICoordinate> points) {
super(null, null, points);
}
@Override
public void paint(Graphics g, List<Point> points) {
Graphics2D g2d = (Graphics2D) g.create();
g2d.setColor(getColor());
g2d.setStroke(getStroke());
Path2D path = buildPath(points);
g2d.draw(path);
g2d.dispose();
}
private Path2D buildPath(List<Point> points) {
Path2D path = new Path2D.Double();
if (points != null && points.size() > 0) {
Point firstPoint = points.get(0);
path.moveTo(firstPoint.getX(), firstPoint.getY());
for (Point p : points) {
path.lineTo(p.getX(), p.getY());
}
}
return path;
}
}
private static void createAndShowUI() {
JFrame frame = new JFrame("Demo");
JMapViewer viewer = new JMapViewer();
List<Coordinate> coordinates = new ArrayList<Coordinate>();
coordinates.add(new Coordinate(50, 10));
coordinates.add(new Coordinate(52, 15));
coordinates.add(new Coordinate(55, 15));
MapPolyLine polyLine = new MapPolyLine(coordinates);
viewer.addMapPolygon(polyLine);
frame.add(viewer);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationByPlatform(true);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowUI();
}
});
}
}
关于java - 在 JMapViewer 中绘制折线,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/20252592/