我有一组精灵，我在Java游戏中调用，当我有3个精灵时，它工作正常，但是当我添加第四个精灵时，重绘方法只会每隔一次调用一次。
这是我的最小例子，
主要课程：
public class Maze extends JPanel implements ActionListener{
/**
* @param args
*/
int stage;
int dir;
int x = 32;
int y = 32;
Rectangle r = new Rectangle(x,y,10,10);
Draw D = new Draw();
public static ArrayList<Rectangle> walls = new ArrayList<Rectangle>();
public ArrayList<Image> spritesl = new ArrayList<Image>();
public ArrayList<Image> spritesd = new ArrayList<Image>();
public ArrayList<Image> spritesr = new ArrayList<Image>();
public ArrayList<Image> spritesu = new ArrayList<Image>();
BufferedImage image;
public Maze() throws IOException{
setBackground(Color.black);
setSize(672,672);
Timer timer = new Timer(2000,this);
timer.addActionListener(this);
timer.start();
//add sprites
for(int i = 1; i<5; i += 1){
spritesl.add(image = ImageIO.read(new File("C:/Users/Dave/Desktop/Sprites/left" + i + ".png")));
}
for(int i = 1; i<5; i += 1){
spritesd.add(image = ImageIO.read(new File("C:/Users/Dave/Desktop/Sprites/down" + i + ".png")));
}
for(int i = 1; i<5; i += 1){
spritesr.add(image = ImageIO.read(new File("C:/Users/Dave/Desktop/Sprites/right" + i + ".png")));
}
for(int i = 1; i<5; i += 1){
spritesu.add(image = ImageIO.read(new File("C:/Users/Dave/Desktop/Sprites/up" + i + ".png")));
}
}
public static void main(String[] args) throws IOException {
JFrame frame = new JFrame();
Maze ate = new Maze();
frame.addKeyListener(new Input());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(ate);
frame.setPreferredSize(new Dimension(688, 709));//16, 37
frame.setVisible(true);
frame.pack();
}
@Override
public void paintComponent(Graphics g){
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
//call wall drawer
g.setColor(Color.gray);
D.draw(g);
g.setColor(Color.red);
//set animation
if(dir == 1){
g.drawImage(spritesu.get(stage-1),x,y, this);
}else if(dir == 2){
g.drawImage(spritesr.get(stage-1),x,y, this);
}else if(dir == 3){
g.drawImage(spritesd.get(stage-1),x,y, this);
}else if(dir == 4){
g.drawImage(spritesl.get(stage-1),x,y, this);
}
System.out.println("set");
}
@Override
public void actionPerformed(ActionEvent e) {
boolean up =false;
boolean right =false;
boolean down =false;
boolean left =false;
//next part tests each direction for collisions
if(Input.right){
right = true;
x += 4;
if(x>672-32){
x -= 4;
right = false;
}else{
for(int i = 0; i < walls.size(); i += 1){
if(new Rectangle(x, y, 30, 30).intersects(walls.get(i))){
x -= 4;
right = false;
}
}
}
}
if(Input.left){
left = true;
dir=4;
x-=4;
if(x<0){
x += 4;
left = false;
}else{
for(int i = 0; i < walls.size(); i += 1){
if(new Rectangle(x, y, 32, 32).intersects(walls.get(i))){
x += 4;
left = false;
}
}
}
}
if(Input.down){
down = true;
dir=3;
y+=4;
if(y>672-32){
y -= 4;
down = false;
}else{
for(int i = 0; i < walls.size(); i += 1){
if(new Rectangle(x, y, 32, 32).intersects(walls.get(i))){
y -= 4;
down = false;
}
}
}
}
if(Input.up){
up = true;
dir=1;
y-=4;
if(y<0){
y += 4;
up = false;
}else{
for(int i = 0; i < walls.size(); i += 1){
if(new Rectangle(x, y, 32, 32).intersects(walls.get(i))){
y += 4;
up = false;
}
}
}
}
//sets direction of animation
if(left||down||right||up){
if(left){
dir = 4;
}
if(down){
dir = 3;
}
if(right){
dir = 2;
}
if(up){
dir = 1;
}
stage += 1;
if(stage >= 4 || stage <= 0){
stage = 1;
}
System.out.println(stage);
}
repaint();
}
}
我的输入测试器（可能没有必要，但游戏需要运行）：
public class Input implements KeyListener {
public static boolean left = false;
public static boolean right = false;
public static boolean up = false;
public static boolean down = false;
public static boolean space = false;
//test for keys
@Override
public void keyPressed(KeyEvent e) {
int key = e.getKeyCode();
if (key == KeyEvent.VK_LEFT)
left = true;
if (key == KeyEvent.VK_RIGHT)
right = true;
if (key == KeyEvent.VK_UP)
up = true;
if (key == KeyEvent.VK_DOWN)
down = true;
if (key == KeyEvent.VK_SPACE)
space = true;
}
@Override
public void keyReleased(KeyEvent e) {
int key = e.getKeyCode();
if (key == KeyEvent.VK_LEFT)
left = false;
if (key == KeyEvent.VK_RIGHT)
right = false;
if (key == KeyEvent.VK_UP)
up = false;
if (key == KeyEvent.VK_DOWN)
down = false;
if (key == KeyEvent.VK_SPACE)
space = false;
}
@Override
public void keyTyped(KeyEvent e) {}
}
和我的Draw课程：
public class Draw {
public void draw(Graphics g){
//draw everything
Maze.walls.clear();
g.fillRect(0, 0, 672, 32);
g.fillRect(0, 0, 32, 672);
g.fillRect(0, 640, 320, 32);
g.fillRect(352, 640, 320, 32);
g.fillRect(640, 0, 32, 320);
g.fillRect(640, 352, 32, 320);
Maze.walls.add(new Rectangle(0, 0, 672, 32));
Maze.walls.add(new Rectangle(0, 0, 32, 672));
Maze.walls.add(new Rectangle(0, 640, 320, 32));
Maze.walls.add(new Rectangle(352, 640, 320, 32));
Maze.walls.add(new Rectangle(640, 0, 32, 320));
Maze.walls.add(new Rectangle(640, 352, 32, 320));
}
}
现在，这可以工作并循环三个阶段，但是一旦我将阶段max更改为5，它只会在阶段2和4上绘制，这两个阶段完全相同。谁能告诉我我做错了什么？
答案 0 :(得分：2)
Swing＆＃34; Timer默认情况下合并事件。＆＃34;正如@HOFE所指出的那样，重新读取精灵图像可能会使事情变慢，从而触发效果。相反，在程序启动时将图像读入List<Image>。