用坐标列表更新G2D

I want to make a program to simulate ants.Let's say I have 100 ants and every one of them has coordinates (2 integers). I use the Java Graphics (Graphics2D).

我想制作一个程序来模拟蚂蚁。假设有100只蚂蚁，每只蚂蚁都有坐标(2个整数)我使用Java图形(Graphics2D)。

Now I want a class that reads a list like that:

现在我想要一个类来读这样的列表:

List<List<Integer>> list = new ArrayList();

This list has for example:

例如，这个列表有:

[100,200],[200,100]

[100200],[200100]

as coordinates in it. Now I want the class to update al the time and delete all "dots" (ants) and after that draw them new with the coordinates out of the List.

作为坐标。现在我想让类更新时间和删除所有的“点”(蚂蚁)，然后用列表中的坐标把它们画出来。

Right now this won't work.

现在这行不通。

public class FrameHandler {

Panel panel  = new Panel();

public FrameHandler() {
    //initialize frame
    frame.repaint();

    List<List<Integer>> test = new ArrayList();
    List<Integer> t1 = new ArrayList();
    t1.add(100);
    t1.add(200);
    test.add(gunther);

    frame.add(panel);

    panel.setList(test);

    //the thread sleeps for 5 seconds

    List<Integer> t2 = new ArrayList();
    t2.add(100);
    t2.add(100);
    test.add(gunther2);

    panel.removeAll();

    panel.setList(olaf);
}


public void setList(List<Integer> list) {
    panel.setList(list);
}

public void setSize(int width, int height) {
    frame.setSize(width, height);
}

private class Panel extends JPanel {

    List<List<Integer>> antList = new ArrayList();

    private void doDrawing(Graphics g) {

        Graphics2D g2d = (Graphics2D) g;

        for(int i = 0; i < antList.size(); i++) {
            g2d.fillRect(antList.get(i).get(0), antList.get(i).get(1), 2, 2);
        }
    }

    @Override
    public void paintComponent(Graphics g) {

        super.paintComponent(g);
        doDrawing(g);
    }

    public void setList(List<List<Integer>> list) {
        antList = list;
    }
}

}

If you have another idea how to solve the problem, maybe with an API or another method of doing graphics I would be happy to hear it.

如果您对如何解决这个问题有其他的想法，也许可以使用API或其他处理图形的方法，我很乐意听到它。

1 个解决方案

#1

Now I want the class to update al the time and delete all "dots" (ants) and after that draw them new with the coordinates out of the List.

现在我想让类更新时间和删除所有的“点”(蚂蚁)，然后用列表中的坐标把它们画出来。

This is basically how painting works in Swing, on each paint cycle, you are expected to repaint the entire state of the component from scratch. See Painting in AWT and Swing for more details.

这就是在Swing中绘制的基本原理，在每个绘制周期中，您需要从头重新绘制组件的整个状态。在AWT中可以看到绘画，可以看到更多的细节。

So the question becomes, how do you update the List. While there are a number ways you might do this, using a Swing Timer might be the simplest (and generally the safest). See How to use Swing Timers for more details.

问题是，如何更新列表。虽然有很多方法可以做到这一点，但是使用Swing计时器可能是最简单的(通常也是最安全的)。有关更多细节，请参见如何使用Swing计时器。

import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class FrameHandler {

    public static void main(String[] args) {
        new FrameHandler();
    }

    public FrameHandler() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public static class TestPane extends JPanel {

        protected static final Random RANDOM_DELTA = new Random();

        private List<List<Integer>> ants;

        public TestPane() {
            Random rnd = new Random();
            ants = new ArrayList<>(25);
            for (int index = 0; index < 10; index++) {
                List<Integer> ant = new ArrayList<>(2);
                // You should also have a look at the java.awt.Point class :P
                ant.add(rnd.nextInt(200 - 2)); //x
                ant.add(rnd.nextInt(200 - 2)); //y
                ants.add(ant);
            }

            Timer timer = new Timer(40, new ActionListener() {
                @Override
                public void actionPerformed(ActionEvent e) {

                    for (List<Integer> ant : ants) {
                        int xDelta = randomDelta();
                        int yDelta = randomDelta();

                        int x = ant.get(0) + xDelta;
                        int y = ant.get(1) + yDelta;

                        if (x < 0) {
                            x = 0;
                        } else if (x + 2 > getWidth()) {
                            x = getWidth() - 2;
                        }
                        if (y < 0) {
                            y = 0;
                        } else if (y + 2 > getHeight()) {
                            y = getHeight() - 2;
                        }

                        ant.set(0, x);
                        ant.set(1, y);
                    }
                    repaint();

                }
            });
            timer.start();
        }

        protected int randomDelta() {
            int delta = 0;
            do {
                double rnd = Math.random();
                delta = rnd < 0.5d ? -1 : 1;
            } while (delta == 0);
            return delta;
        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(200, 200);
        }

        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            Graphics2D g2d = (Graphics2D) g.create();
            for (List<Integer> ant : ants) {
                g2d.fillRect(ant.get(0), ant.get(1), 2, 2);
            }
            g2d.dispose();
        }

    }

}

This example basically generates a random delta (change in direction) for each ant's x & y coordinate. I suspect you might need to have something a little more sophisticated

这个例子基本上是为每个蚂蚁的x和y坐标生成一个随机的增量(方向变化)。我想你可能需要一些更复杂的东西