几何：最接近的点对

Question

这周我在Java作业上有些停滞。 问题听起来像是这样：“编写一个程序，让用户单击面板以动态创建点。最初，面板为空。当面板具有两个或多个点时，突出显示一对最接近的点。每当一个新点创建后，将突出显示一对新的最近的点。使用小圆圈显示这些点，并使用实心圆圈突出显示这些点。（提示：将这些点存储在ArrayList中）“

在下面的代码中，我尝试制作CircleMouse类的ArrayList，但是我不知道这是否是“正确”的方法？ 此外，当ArrayList中的圆圈时，如何在面板中显示圆圈？

import java.awt.*;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.util.ArrayList;

import javax.swing.*;

class ClosestPairOfPoints extends JFrame {

  /** FRIE VARIABLER **/
  int x, y;

  /*** ARRAYLIST MED ALLE SIRKLENE ***/
  public ArrayList<CircleMouse> arrCircle = new ArrayList <CircleMouse>();

  public ClosestPairOfPoints() {
    /*** PANEL FOR Å HOLDE PÅ SIRKLENE ***/
    JPanel circlePanel = new JPanel();
    circlePanel.setSize(500, 400);
    circlePanel.setLocation(0, 0);
    circlePanel.setBackground(Color.PINK);

    /*** HENTER CIRCLEMOUSE KLASSEN INN ***/
    CircleMouse circleMouse = new CircleMouse();
    circlePanel.addMouseListener(circleMouse);
    circlePanel.addMouseMotionListener(circleMouse);

    /*** LEGGER PANELET INN I FRAMEN ***/
    add(circlePanel);

}

/*** CIRCLEMOTION KLASSEN ***/
class CircleMouse extends JPanel implements MouseListener, MouseMotionListener {

    public void paintComponent (Graphics g) {
        super.paintComponent(g);
        g.setColor(Color.BLUE);
        g.drawOval(x, y, 15, 15);
    }

    @Override
    public void mouseDragged(MouseEvent e) {
        // TODO Auto-generated method stub

    }

    @Override
    public void mouseMoved(MouseEvent e) {
        // TODO Auto-generated method stub

    }

    @Override
    public void mouseClicked(MouseEvent e) {
        x = e.getX();
        y = e.getY();
        repaint();


    }

    @Override
    public void mouseEntered(MouseEvent e) {
        // TODO Auto-generated method stub

    }

    @Override
    public void mouseExited(MouseEvent e) {
        // TODO Auto-generated method stub

    }

    @Override
    public void mousePressed(MouseEvent e) {
        // TODO Auto-generated method stub

    }

    @Override
    public void mouseReleased(MouseEvent e) {
        // TODO Auto-generated method stub

    }

}

public static void main(String[] args) {
    ClosestPairOfPoints frame = new ClosestPairOfPoints();
    frame.setTitle("Øving 1 - Oppgave 1: Closest Pair Of Points");
    frame.setLocationRelativeTo(null);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setSize(500, 400);
    frame.setVisible(true);
}

}

Answer 1

我试图做一个CircleMouse类的ArrayList

听起来不太正确。 您应该具有Point的ArrayList 。 每次调用mouseClicked ，都应将MouseEvent的Point添加到其中，然后使用paintComponent方法在此列表上进行迭代并绘制“点”

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