我正在创建一个使用 JFrame、JPanel、JLabel 和所有其他类型的 swing 组件的程序。
我想要做的是在专用于该动画的单独 JPanel 上创建 2D 动画。所以我将重写 PaintComponent (Graphics g) 方法。
我有使用 for 循环 + 线程制作动画的经验，但我听说线程对于 swing 不安全。
因此，使用 Runnable 接口制作动画是否安全？如果不是，我应该使用什么（例如计时器），请给出一个关于如何最好使用它的小例子（或网页链接）。
EDIT:
感谢 Jeff，我将使用 Timer 来创建动画。对于这个问题的未来观众，这是我在大约 5 分钟内编写的一个快速程序，请原谅脏代码。
我还添加了一些快速评论。
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
class JFrameAnimation extends JFrame implements ActionListener
{
JPanel panel;
Timer timer;
int x, y;
public JFrameAnimation ()
{
super ();
setDefaultCloseOperation (EXIT_ON_CLOSE);
timer = new Timer (15, this); //@ First param is the delay (in milliseconds) therefore this animation is updated every 15 ms. The shorter the delay, the faster the animation.
//This class iplements ActionListener, and that is where the animation variables are updated. Timer passes an ActionEvent after each 15 ms.
}
public void run ()
{
panel = new JPanel ()
{
public void paintComponent (Graphics g) //The JPanel paint method we are overriding.
{
g.setColor (Color.white);
g.fillRect (0, 0, 500, 500); //Setting panel background (white in this case);
//g.fillRect (-1 + x, -1 + y, 50, 50); //This is to erase the black remains of the animation. (not used because the background is always redrawn.
g.setColor (Color.black);
g.fillRect (0 + x, 0 + y, 50, 50); //This is the animation.
}
}
;
panel.setPreferredSize (new Dimension (500, 500)); //Setting the panel size
getContentPane ().add (panel); //Adding panel to frame.
pack ();
setVisible (true);
timer.start (); //This starts the animation.
}
public void actionPerformed (ActionEvent e)
{
x++;
y++;
if (x == 250)
timer.stop (); //This stops the animation once it reaches a certain distance.
panel.repaint (); //This is what paints the animation again (IMPORTANT: won't work without this).
panel.revalidate (); //This isn't necessary, I like having it just in case.
}
public static void main (String[] args)
{
new JFrameAnimation ().run (); //Start our new application.
}
}
