好的，我们开始：
package animationissue;
import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JFrame;
import javax.swing.JLayeredPane;
import javax.swing.JPanel;
public class AnimationIssue extends JFrame {
JPanel a = new JPanel() {
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
System.out.println("map has become repainted");
}
};
JPanel b = new JPanel() {
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
System.out.println("menu as well");
}
};
public AnimationIssue() {
this.setSize(500, 500);
this.setLayout(null);
a.setSize(400, 400);
b.setSize(400, 200);
this.getLayeredPane().add(a, JLayeredPane.DEFAULT_LAYER); // Map
this.getLayeredPane().add(b, JLayeredPane.PALETTE_LAYER); // Menu
a.setLocation(0, 0);
b.setLocation(0, 100);
a.setBackground(Color.red);
b.setBackground(Color.blue);
Thread t = new Thread(new Runnable() {
@Override
public void run() {
// doin some computations for animation
// cast a repaint after having finished new
//animation information i.e. interpolation
while (true) {
try {
Thread.sleep(2000);
} catch (Exception e) {
}
// case 1 - just a repaint of the whole component - triggering map redraw results in menu redraw
// a.repaint();
// case 2 - repaint of specified rectangle
// Either passing one - the menu does not get repainted, or passing both - menu also gets repainted
//a.repaint(0, 0, 400, 100);
//a.repaint(0, 300, 400, 100);
// paintimmediately works for now
//a.paintImmediately(0, 0, 400, 100);
//a.paintImmediately(0, 300, 400, 100);
// Just repainting Menu does not trigger map to become repainted, except if its opague, but then it should become repainted
b.repaint();
}
}
});
t.start();
}
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
AnimationIssue f = new AnimationIssue();
f.setVisible(true);
}
}
我真的很期待优化行为，如果没有必要，不会重绘菜单。您必须将菜单想象成一个包含多个 JList 的组件，其中包含大量 String 绘制任务，这对 cpu 使用率确实有巨大影响。我一直不知道，因为它每秒重绘大约 25 次。
如果使用paintImmediately 是正确的，我只是不确定当前的解决方案。除此之外-如果您或某人有替代方法-更好的方法来防止无用的重绘（我真的认为 Glasspane 或 JLayeredPane 或 isOptimizedDrawing 或 isOpaque 可能会有所帮助），我真的很感激。
此致。