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問題是當我調整JFrame的大小時，動畫會繼續使用Pre的尺寸JComponent。有沒有辦法可以在我調整JFrame的大小時更新我的width和height變量，以便動畫可以與新的座標一起運行。Swing中的球動畫
簡單來說，說JComponent具有初始width = 300和height = 300，所以這裏面的BALL移動指定Co-ordinates。現在，如果我調整JFrame的大小，則JComponent的大小仍然保持原樣，即width = 300和height = 300，但我期望的是使用當前窗口大小修改這些變量的方法。如果我沒有解釋我的問題，請告訴我。
這裏是我使用的代碼：我希望你只需要綁定一些品種監聽器（？WindowEventListener）的
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class BallAnimation
{
private int x;
private int y;
private int count;
private int width;
private int height;
private int speedValue;
private boolean flag;
/*
* These variables are used to keep track of
* the ball, either it is going LEFT or RIGHT
* depending on that, we will set the
* Co-ordinates.
*/
private boolean toLeft, toRight;
private boolean fromTop, fromBottom;
private Timer timer;
private JButton button;
private ActionListener actionTimer;
private ActionListener buttonAction;
public BallAnimation()
{
x = y = count = 0;
flag = toLeft = false;
toRight = true;
fromTop = true;
fromBottom = false;
speedValue = 5;
}
public static void main(String args[])
{
Runnable runnable = new Runnable()
{
public void run()
{
BallAnimation animation = new BallAnimation();
animation.go();
}
};
SwingUtilities.invokeLater(runnable);
}
public void go()
{
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//JPanel contentPane = new JPanel();
/*
* Class Name :
* Java Naming Convention says that class names
* should be in Pascal Case, i.e. the first
* letter of the class name should be capitalized
* and every new word must start with a capitalized
* Alphabet.
* For Example :
* public class ClassName{...}
* ----------------------------------------------------------
* Variable Name :
* Java Naming Convention says that the variable name
* should be in Camel Case, i.e. the first letter of
* the variable name should be small case or _ (underscore)
* and every new word must start with a capitalized
* Alphabet.
* ---------------------------------------------------------
*/
final MyDraw drawPanel = new MyDraw(0, 0);
x = drawPanel.getXValue();
y = drawPanel.getYValue();
//contentPane.add(drawPanel);
actionTimer = new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
if (fromTop && !fromBottom && x < width && y < height
&& toRight && !toLeft)
{
x += speedValue;
y += speedValue;
}
else if (fromTop && !fromBottom && x < width && y >= height
&& toRight && !toLeft)
{
/*
* Since the ball coming from the TOP LEFT Side
* touched the BOTTOM of the JPanel.
*/
y -= speedValue;
x += speedValue;
fromTop = false;
fromBottom = true;
}
else if (!fromTop && fromBottom && x < width && y <= 0
&& toRight && !toLeft)
{
/*
* Since the ball coming from BOTTOM LEFT Side
* touched the TOP of the JPanel.
*/
fromTop = true;
fromBottom = false;
x += speedValue;
y += speedValue;
}
else if (!fromTop && fromBottom && x < width && y < height
&& toRight && !toLeft)
{
x += speedValue;
y -= speedValue;
}
else if (!fromTop && fromBottom && x >= width && y < height
&& toRight && !toLeft)
{
/*
* Since the ball coming from the BOTTOM LEFT Side
* touched the RIGHT Side of the JPanel.
*/
toRight = false;
toLeft = true;
x -= speedValue;
y -= speedValue;
}
else if (!fromTop && fromBottom && x < width && y <= 0
&& !toRight && toLeft)
{
/*
* Since the ball coming from the BOTTOM RIGHT Side
* touched the Top Side of the JPanel.
*/
fromTop = true;
fromBottom = false;
x -= speedValue;
y += speedValue;
}
else if (fromTop && !fromBottom && x <= 0 && y < height
&& !toRight && toLeft)
{
/*
* Since the ball coming from the TOP RIGHT Side
* touched the LEFT Side of the JPanel.
*/
toRight = true;
toLeft = false;
x += speedValue;
y += speedValue;
}
else if (fromTop && !fromBottom && x >= width && y < height
&& toRight && !toLeft)
{
/*
* Since the ball coming from the TOP LEFT Side
* touched the RIGHT Side of the JPanel
*/
toRight = false;
toLeft = true;
x -= speedValue;
y += speedValue;
}
else if (fromTop && !fromBottom && x < width && y < height
&& !toRight && toLeft)
{
x -= speedValue;
y += speedValue;
}
else if (!fromTop && fromBottom && x <= 0 && y < height
&& !toRight && toLeft)
{
/*
* Since the ball coming from the BOTTOM RIGHT Side
* touched the LEFT Side of the JPanel.
*/
toRight = true;
toLeft = false;
x += speedValue;
y -= speedValue;
}
else if (!fromTop && fromBottom && x < width && y < height
&& !toRight && toLeft)
{
x -= speedValue;
y -= speedValue;
}
else if (fromTop && !fromBottom && x < width && y >= height
&& !toRight && toLeft)
{
/*
* Since the ball coming from the TOP RIGHT Side
* touched the BOTTOM Side of the JPanel.
*/
fromTop = false;
fromBottom = true;
x -= speedValue;
y -= speedValue;
}
System.out.println("X : " + x);
System.out.println("Y : " + y);
System.out.println("Direction is LEFT : " + toLeft);
System.out.println("Direction is RIGHT : " + toRight);
System.out.println("Coming from TOP : " + fromTop);
System.out.println("Coming from BOTTOM : " + fromBottom);
drawPanel.setXYValues(x, y);
}
};
buttonAction = new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
if (!flag)
{
timer.start();
button.setText("STOP ANIMATION");
flag = true;
}
else if (flag)
{
timer.stop();
button.setText("START ANIMATION");
flag = false;
}
}
};
button = new JButton("START ANIMATION");
button.addActionListener(buttonAction);
frame.getContentPane().add(drawPanel, BorderLayout.CENTER);
frame.getContentPane().add(button, BorderLayout.PAGE_END);
frame.setSize(300, 300);
//frame.pack();
frame.setVisible(true);
timer = new Timer(40, actionTimer);
width = drawPanel.getWidth() - 30;
System.out.println("WIDTH : " + width);
height = drawPanel.getHeight() - 30;
System.out.println("HEIGHT : " + height);
}
class MyDraw extends JComponent
{
private int x;
private int y;
private Timer timer;
public MyDraw(int x, int y)
{
this.x = x;
this.y = y;
}
public int getXValue()
{
return x;
}
public int getYValue()
{
return y;
}
public void setXYValues(int x, int y)
{
this.x = x;
this.y = y;
repaint();
}
public Dimension getPreferredSize()
{
return (new Dimension(300, 300));
}
public void paintComponent(Graphics g)
{
g.setColor(Color.WHITE);
g.fillRect(0, 0, getWidth(), getHeight());
g.setColor(Color.BLUE);
g.fillOval(x, y, 40, 40);
}
}
}
你知道你的大量if邏輯可以被壓縮到1/4的大小，代碼少得多，對吧？使用x和y速度（可能是負數）將消除布爾標誌，將所有移動代碼轉換爲'x + = xVel; y + = yVel;'，然後您只剩下out-of-邊界檢查，將球推回到邊界內，並反轉相關的速度。 – zebediah49 2012-03-21 08:35:57
@ zebediah49：可以請你在你的回答中詳細說明邏輯thingy :-) – 2012-03-21 08:55:22
這是一段7年左右的代碼，所以圖形處理相當不推薦。無論如何，控制和牆壁邏輯是標準的。這是因爲它具有固體（反彈）和週期性（！反彈）邊界條件。 http://pastebin.com/UT8fyAaB – zebediah49 2012-03-21 09:35:49