Java Swing 动画看起来不稳定。如何让它看起来专业？

Question

更新:半复杂动画 + Swing 计时器 = trainwreck。问题的最终根源是 java 计时器，swing 或实用程序版本。它们不可靠，尤其是在跨操作系统比较性能时。通过实现普通线程，程序在所有系统上运行都非常流畅。 http://zetcode.com/tutorials/javagamestutorial/animation/ .此外，将 Toolkit.getDefaultToolkit().sync() 添加到 paintComponent() 方法中会有显着帮助。

我在 awt.Applet 中编写了一些动画流畅的代码(但闪烁)，然后我将其重构为 java swing。现在它不闪烁，但看起来波涛汹涌。我弄乱了计时器，但这不起作用。任何有关平滑 Swing 组件动画的提示或建议将不胜感激。

import java.util.Random;
import java.util.ArrayList;
import java.awt.event.<em>;
import java.awt.</em>;
import javax.swing.*;
//////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////<p></p>

<p>public class Ball extends JApplet{</p>

<pre><code>public static void main(String[] args) {
    SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            JFrame frame = new JFrame();
            frame.setTitle("And so the ball rolls");
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            initContainer(frame);
            frame.pack();
            frame.setVisible(true);
        }
    });
}
public static void initContainer(Container container){

   GraphicsPanel graphicsPanel = new GraphicsPanel();
   MainPanel mainPanel = new MainPanel(graphicsPanel);
   container.add(mainPanel);
   graphicsPanel.startTimer();

}

@Override
public void init(){
    initContainer(this);
}
</code></pre>

<p>}
    ///////////////////////////////////////////////////////////////////////
    //////////////////////////////////////////////////////////////////////
    class MainPanel extends JPanel {
        JLabel label = new JLabel("Particles");
        GraphicsPanel gPanel;</p>

<pre><code>    public MainPanel(GraphicsPanel gPanel){
        this.gPanel = gPanel;
        add(gPanel);
        add(label);
    }
</code></pre>

<p>}
    ///////////////////////////////////////////////////////////////////////
    //////////////////////////////////////////////////////////////////////
    class GraphicsPanel extends JPanel implements MouseListener {</p>

<pre><code>    private ArrayList<Particle> ballArr = new ArrayList<Particle>();
    private String state="s";         //"s"=spiral, "p"=particle
    private int speed=10;             //~20 Hz
    private Timer timer;

    public GraphicsPanel(){
        System.out.println("echo from gpanel");
        setPreferredSize(new Dimension(500,500));
        timer = new Timer(speed, new TimerListener());
        addMouseListener(this);
    }

    public void startTimer(){
        timer.start();
    }

    @Override
    public void paintComponent(Graphics g){

        super.paintComponent(g);
         for (Particle b: ballArr){
              g.setColor(b.getColor());
              g.fillOval(b.getXCoor(),b.getYCoor(),
                         b.getTheSize(),b.getTheSize());
         }
    }

    public void mousePressed(MouseEvent e) {
        ballArr.add(new Particle(e.getX(), e.getY(), state));
    }
    public void mouseReleased(MouseEvent e) {}
    public void mouseEntered(MouseEvent e){}
    public void mouseExited(MouseEvent e){}
    public void mouseClicked(MouseEvent e) {}

    class TimerListener implements ActionListener {
        public void actionPerformed(ActionEvent e){
             for (Particle b: ballArr)
                 b.move();
             setBackground(Color.WHITE);
             repaint();

        }
    }
</code></pre>

<p>}</p>

<p>//////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////
class Particle
{
    private static int instanceCount; {{instanceCount++;}}
    private int z = 11, t=1, u=1;
    private int[] RGB = new int[3];
    private int[] randomizeColor = new int[3];
    private double radius, theta;
    private int x, y, centerX, centerY, size, spiralDirection=1,
                ballSizeLowerBound, ballSizeUpperBound,
                radiusLowerBound, radiusUpperBound,
                mouseInputX, mouseInputY,
                radiusXMultiplier, radiusYMultiplier;
    private Color color;
    private String state;
    private Random random = new Random();
    ///////////////////////////////////////////////////////////////////////////
    public Particle(int x, int y, int centerX, int centerY, int radius,
                int theta, int size, Color color){
        this.x=x;this.y=y;this.centerX=centerX;this.centerY=centerY;
        this.radius=radius;this.theta=theta;this.size=size;this.color=color;
    }</p>

<code>public Particle(int mouseInputX, int mouseInputY, String state){
    this.mouseInputX=mouseInputX;
    this.mouseInputY=mouseInputY;
    this.state=state;
   //randomize color
    RGB[0] = random.nextInt(252);
    RGB[1] = random.nextInt(252);
    RGB[2] = random.nextInt(252);
    randomizeColor[0] = 1+random.nextInt(3);
    randomizeColor[0] = 1+random.nextInt(3);
    randomizeColor[0] = 1+random.nextInt(3);
    centerX=mouseInputX;
    centerY=mouseInputY;
    if (state.equals("s")){ //setup spiral state
        ballSizeLowerBound=5;
        ballSizeUpperBound=18;
        radiusLowerBound=0;
        radiusUpperBound=50;
        radiusXMultiplier=1;
        radiusYMultiplier=1;
    }
    if (state.equals("p")){ //setup particle state
        ballSizeLowerBound = 15;
        ballSizeUpperBound =20 + random.nextInt(15);
        radiusLowerBound = 5;
        radiusUpperBound = 15+ random.nextInt(34);
        radiusXMultiplier=1 + random.nextInt(3);
        radiusYMultiplier=1 + random.nextInt(3);
    }

    size = ballSizeUpperBound-1; //ball size
    radius = radiusUpperBound-1;

    if (instanceCount %2 == 0) // alternate spiral direction
        spiralDirection=-spiralDirection;
}
///////////////////////////////////////////////////////////////////////////
public int getXCoor(){return centerX+x*spiralDirection;}
public int getYCoor(){return centerY+y;}
public int getTheSize(){return size;}
public Color getColor(){return color;}
//////////////////////////////////////////////////////////////////////////
void move(){

        //spiral: dr/dt changes at bounds
        if (radius > radiusUpperBound || radius < radiusLowerBound)
            u = -u;

        //spiral shape formula: parametric equation for the
        //polar equation radius = theta
        x = (int) (radius * radiusXMultiplier * Math.cos(theta));
        y = (int) (radius * radiusYMultiplier * Math.sin(theta));

        radius += .1*u;
        theta += .1;

        //ball size formula
        if (size == ballSizeUpperBound || size == ballSizeLowerBound)
            t = -t;
        size += t;

        //ball colors change
        for (int i = 0; i < RGB.length; i++)
            if (RGB[i] >= 250 || RGB[i] <= 4)
                randomizeColor[i] = -randomizeColor[i];

        RGB[0]+= randomizeColor[0];
        RGB[1]+= randomizeColor[1];
        RGB[2]+= randomizeColor[2];
        color = new Color(RGB[0],RGB[1],RGB[2]);
}
</code>





}


Answer 1

不要设置固定间隔计时器。将定时器设置为关闭一次——在处理程序中

1. 获取当前时间(保存在frameStartTime中)
2. 做你的框架
3. 将计时器设置为在以下时间内关闭:interval - (newCurrentTime - frameStartTime)

应该更流畅。如果您想成为真正的专家(并继续使用 Java)，我认为您必须考虑 JavaFX。