有点粗略的java,但有人可以告诉我如何从对象列表中获取绘制方法,比如说有超过1个框,并将它放在actionPerform中,这样我就可以修改{的getter {1}}和X
到Y
他们并让他们搬家?
来自repaint()
班级:
Box
public void draw(Graphics g) {
g.setColor(Color.BLUE);
g.fillRect((int) (getX() - (width/2)), (int) (getY() - (height/2)), getWidth(), getHeight());
}
方法:(这是另一个类)
actionPerform
答案 0 :(得分:1)
基本理念是......
调用actionPerformed
时......
然后在您的组件paintComponent
方法中,迭代列表并绘制它们
以下是一个非常基本的概念......
import java.awt.BorderLayout;
import java.awt.Color;
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 javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class FlyingBoxes {
public static void main(String[] args) {
new FlyingBoxes();
}
public interface Drawable {
public void update(JComponent comp);
public void draw(Graphics g);
}
public class Box implements Drawable {
private int x;
private int y;
private int width = 10;
private int height = 10;
private int xDelta;
private int yDelta;
public Box(int x, int y) {
this.x = x;
this.y = y;
xDelta = random();
yDelta = random();
}
@Override
public void update(JComponent comp) {
x += xDelta;
y += yDelta;
if (x < 0) {
x = 0;
xDelta *= -1;
} else if (x + width > comp.getWidth()) {
x = comp.getWidth() - width;
xDelta *= -1;
}
if (y < 0) {
y = 0;
yDelta *= -1;
} else if (y + height > comp.getHeight()) {
y = comp.getHeight() - height;
yDelta *= -1;
}
}
@Override
public void draw(Graphics g) {
g.setColor(Color.BLUE);
g.fillRect(x, y, width, height);
}
protected int random() {
int value = 0;
do {
value = -2 + (int)(Math.random() * 4);
} while (value == 0);
return value;
}
}
public FlyingBoxes() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private List<Drawable> drawables;
public TestPane() {
drawables = new ArrayList<>(25);
for (int index = 0; index < 25; index++) {
int x = (int) (Math.random() * 190);
int y = (int) (Math.random() * 190);
drawables.add(new Box(x, y));
}
Timer timer = new Timer(40, new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
for (Drawable d : drawables) {
d.update(TestPane.this);
}
repaint();
}
});
timer.start();
}
@Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
for (Drawable d : drawables) {
d.draw(g);
}
}
}
}