因此，在我的代码中，当我按下 W、A、S 或 D 键之一时，我会按照所需的方向重新绘制图形。图形不是从左到右或从上到下平滑移动，它只是变得不可见，有时又变得可见，但如果我放开按下的键，它总是会变得可见。我在另一台计算机上创建了完全相同的程序，并且没有出现此问题，但在我的个人计算机上它始终存在。
import com.sun.glass.events.KeyEvent;
import java.awt.Graphics;
import java.awt.Rectangle;
import java.awt.Shape;
/**
*
* @author Admin
*/
public class mainFrame extends javax.swing.JFrame {
public static int px,py,pwid,phei,ex,ey,ewid,ehei,speed,ppx,ppy;
/**
* Creates new form mainFrame
*/
public mainFrame() {
initComponents();
px = 150;py = 150;pwid = 50;phei = 50;speed = 10000;
}
public void paint(Graphics g){
super.paint(g);
Graphics player = (Graphics)g;
player.drawRect(px, py, pwid, phei);
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
addKeyListener(new java.awt.event.KeyAdapter() {
public void keyPressed(java.awt.event.KeyEvent evt) {
formKeyPressed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 400, Short.MAX_VALUE)
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGap(0, 300, Short.MAX_VALUE)
);
pack();
}// </editor-fold>
private void formKeyPressed(java.awt.event.KeyEvent evt) {
int keycode = evt.getKeyCode();
if(keycode == KeyEvent.VK_D){
repaint(px++*speed);
}if(keycode == KeyEvent.VK_A){
repaint(px--*speed);
}if(keycode == KeyEvent.VK_W){
repaint(py--*speed);
}if(keycode == KeyEvent.VK_S){
repaint(py++*speed);
}
if(px >= 400-42 || px <= 0+42){
px = px - 1;
}else if(py >= 300-42 || py <= 0+42){
System.out.println("You Cant go there");
}
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(mainFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(mainFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(mainFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(mainFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new mainFrame().setVisible(true);
}
});
}
// Variables declaration - do not modify
// End of variables declaration
}
最佳答案
这并不是 repaint(int) 背后的真正想法，相反，您应该有一个“游戏循环”来更新游戏的当前状态并安排重新绘制。
此外，您确实应该避免覆盖顶级容器的paint，因为正如您所发现的，它们不是双缓冲的，这可能会在更新时导致闪烁。 JFrame 还包含一堆其他组件，由于绘画的工作方式，这些组件可以独立于您的容器进行绘制，这意味着它们可以找到您之前绘制的内容
相反，从诸如 JPanel 之类的东西开始，重写其 paintComponent 方法并在其中执行自定义绘制，然后将此面板添加到 JFrame 的实例中
由于多种原因(与焦点相关的问题是主要问题)，您还应该避免使用 KeyListener ，而更喜欢 Key Bindings API
关于java - 重新绘制传送我的图形而不是平滑地移动它，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/34666415/