Which layout can do this?

Question

I\'m trying to layout some JLabels in my application as shown in this example:

Answer 1

You don't need a layout manager which specifically supports this. You can calculate the x, y positions yourself with some fairly simple trigonometry, then use a regular layout such as SpringLayout.

import java.awt.Point;
import java.util.ArrayList;
import java.util.List;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SpringLayout;

public class CircleLayout {

  /**
   * Calculate x,y positions of n labels positioned in
   * a circle around a central point. Assumes AWT coordinate
   * system where origin (0,0) is top left.
   * @param args
   */
  public static void main(String[] args) {
    int n = 6;  //Number of labels
    int radius = 100;
    Point centre = new Point(200,200);

    double angle = Math.toRadians(360/n);
    List points = new ArrayList();
    points.add(centre);

    //Add points
    for (int i=0; i points) {
    JFrame frame = new JFrame("Labels in a circle");
    frame.setSize(500, 500);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    JPanel panel = new JPanel();;
    SpringLayout layout = new SpringLayout();

    int count = 0;
    for (Point point : points) {
      JLabel label = new JLabel("Point " + count);
      panel.add(label);
      count++;
      layout.putConstraint(SpringLayout.WEST, label, point.x, SpringLayout.WEST, panel);
      layout.putConstraint(SpringLayout.NORTH, label, point.y, SpringLayout.NORTH, panel);
    }

    panel.setLayout(layout);

    frame.add(panel);
    frame.setVisible(true);

  }
}