这是一个UI，它使球以对角线的方式下降，但是每次我按下按钮“动画！”时，它不会产生新的球。
另一个问题是“冻结”按钮无法按预期工作，因为它应该先停球，然后才能停球。如果再按一次，应该会使球再次移动。
最终，限制出现了问题，因为当球几乎触到底部时，球没有到达底部并反弹到右侧。同样，当球“触碰”到正确的极限时，它只会上升。
另外，调整框架大小时，限制不会更新。
请下载一个球并更改目录，以便程序可以找到您的球的分配位置。无需下载足球场，但如果需要，可以。最后，我要感谢您花时间寻找这种故障。
球形链接：https://lapequeteria.cl/wp-content/uploads/2018/11/balon-adidas-2.jpeg（设为png）
间距链接：https://www.freejpg.com.ar/asset/900/9c/9ca2/F100004898.jpg
import java.awt.BorderLayout;
import java.awt.Dimension;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.geom.Rectangle2D;
import java.io.IOException;
import java.util.ArrayList;
import javax.imageio.ImageIO;
import java.io.File;
class Animation extends JFrame { //Frame
static boolean running = true;
static Layout panel = new Layout();
JButton animate, stop;
Runnable runnable;
Thread move;
public Animation() {
setLayout(new BorderLayout()); //BorderLayout disposition
setTitle("Pelota en acción");
animate = new JButton("Animate it!"); //Button to create balls
animate.setSize(120,30);
animate.addActionListener(new ActionListener(){
@Override
public void actionPerformed(ActionEvent e) {
panel.createEllipse();
runnable = panel;
move = new Thread(runnable);
panel.X = 0;
panel.Y = 0;
move.start();
}
});
stop = new JButton("Freeze"); //Botón para interrumpir hilo (aun no implementado)
stop.setBounds(0,0,120,30);
stop.addActionListener(new ActionListener(){
@Override
public void actionPerformed(ActionEvent e) {
if(move.isAlive()){
stop.setText("Go"); //Pause
synchronized(move) {
try {
// running = false;
move.wait();
} catch (InterruptedException ex) {
System.out.println("Interrupted");
}
}
}
else {
stop.setText("Freeze"); //Play
synchronized(move) {
// running = true;
move.notifyAll();
}
}
}
});
JPanel subPanel = new JPanel(); //Layout with its buttons situated to the south
subPanel.add(animate);
subPanel.add(stop);
add(subPanel,BorderLayout.SOUTH);
add(panel);
}
public static void main(String[] args) { //Frame construction
Animation ventana = new Animation();
ventana.setSize(850,625);
ventana.setLocationRelativeTo(null);
ventana.setVisible(true);
ventana.setDefaultCloseOperation(EXIT_ON_CLOSE);
}
}
class Layout extends JPanel implements Runnable { //Layout and thread
volatile double X,Y; //Coordinates
volatile double dX=1,dY=1; //Direction
static ArrayList<Image> balls = new ArrayList<>(); //Balls collection
Image picture, ball;
int width = 120,height = 120;
@Override
public void paintComponent(Graphics g) { //Shows the ball and the pitch
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g;
soccerPitch();
g2.drawImage(picture, 0, 0, null);
for (Image ball : balls) { //Balls added to the layout
g2.drawImage(ball,(int)X,(int)Y,100,100,null);
}
}
public void soccerPitch () { //Builds the soccerPitch image
try {
picture = ImageIO.read(new File("C:\\Users\\Home\\Desktop\\NO BORRAR porfavor\\Cancha.jpg"));
} catch (IOException ex) {
System.out.println("Pitch image was not found");
}
}
public void createEllipse () { //Builds the ball image
try {
ball = ImageIO.read(new File("C:\\Users\\Home\\Desktop\\NO BORRAR porfavor\\Pelota.png"));
System.out.println(ball.getWidth(null)+" "+ball.getHeight(null));
} catch(IOException ex) {
System.out.println("Any balls were found");
}
balls.add(ball); //Balls are added to the collection
}
@Override
public void run () { //Moves the ball(coordinate system doesn't work)
moveBall(Animation.panel.getBounds());
}
public void moveBall(Rectangle2D limits) {
while(true) {
// while(Animation.running) {
System.out.println("X: "+X+"\tY: "+Y);
System.out.println(limits.getBounds());
X+=dX;
Y+=dY;
if(X<limits.getMinX()){
X=limits.getMinX();
dX=-dX;
}
if(X + width>=limits.getMaxX()){
X=limits.getMaxX()-width;
dX=-dY;
}
if(Y<limits.getMinY()){
Y=limits.getMinY();
dY=-dY;
}
if(Y + height>=limits.getMaxY()){
Y=limits.getMaxY()-height;
dY=-dY;
}
try {
Thread.sleep(4);
} catch (InterruptedException e) {
System.out.println("Interrupted");
}
repaint();
}
}
}
以防万一你想帮助我；我不是在要求完成的工作，只是向我解释为什么它不起作用。
最佳答案
您似乎违反了Concurrency in Swing的基本规则。加号（而不是using LayoutManagers）是手动设置组件的边界的（这就是为什么在调整框架大小时，组件不在正确的位置）的原因。
现在，您在Thread中启动应用程序，对吗？在此线程中，您准备您的GUI并进行处理，然后在某些时候while(true)。当您while(true)时，线程将“卡在” while循环内，因此不会发生摆动事件。这就是为什么您必须while(true)并在另一个线程中创建动画的原因。但是，在Swing中创建动画的最佳方法是use a Swing Timer.
我创建了一个示例，其中动画是每100毫秒在面板中创建一个新的随机矩形（10x10）。用它做一些到期，并尝试为您的应用程序调整相同的逻辑（毕竟，您不会发布代码，并希望我们为您解决它:)）。
这是示例：
public class Animation extends JFrame implements ActionListener {
private Timer timer;
private RectanglePanel panel;
public Animation() {
super("test");
setDefaultCloseOperation(EXIT_ON_CLOSE);
setLayout(new BorderLayout());
add(panel = new RectanglePanel());
timer = new Timer(100, this); //every 100 ms add new Shape
JButton button = new JButton("Start Animation");
button.addActionListener(e -> timer.start()); //start animation timer
add(button, BorderLayout.PAGE_END);
pack();
setSize(500, 500);
setLocationRelativeTo(null);
}
@Override
public void actionPerformed(ActionEvent e) {
panel.createNewShape(); //add new shape
panel.repaint();
}
private class RectanglePanel extends JPanel {
private List<Rectangle> shapes;
public RectanglePanel() {
super();
this.shapes = new ArrayList<>();
}
public void createNewShape() {
int x = (int) (Math.random() * getWidth());
int y = (int) (Math.random() * getHeight());
x = Math.min(x, getWidth() - 10);
y = Math.min(y, getHeight() - 10);
Rectangle r = new Rectangle(x, y, 10, 10);
System.out.println("New rectangle:" + r);
shapes.add(r);
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
for (Rectangle r : shapes) {
g.setColor(randomColor());
g.drawRect(r.x, r.y, r.width, r.height);
}
}
private Color randomColor() {
return new Color((int) (Math.random() * 255), (int) (Math.random() * 255), (int) (Math.random() * 255));
}
}
public static void main(String[] args) {
//All swing applications must run on their own thread
SwingUtilities.invokeLater(() -> new Animation().setVisible(true));
}
}
预习：