我无法显示按键的次数并在JTextField或JButton中显示该数字。有人能帮我一把吗？
我已经显示了KeyEvent.VK_NUMPAD3，它似乎是KeyEvent.VK_2，我遇到了这样的问题：
我可以显示它，但每次按下该键时数字都不会更新。
这是我的完整代码..有点大，但你要求它...... :)
public class Display extends JFrame{
public static final int CANVAS_WIDTH = 1000;
public static final int CANVAS_HEIGHT = 450;
public static final Color LINE_COLOR = Color.BLACK;
public static final Color GROUND_COLOR = Color.GREEN;
public static final Color CANVAS_BACKGROUND = Color.CYAN;
public static final int TRANS = Color.OPAQUE;
private int x1 = CANVAS_WIDTH / 2;
private int y1 = CANVAS_HEIGHT / 2;
private int x2 = CANVAS_WIDTH /2;
private int y2 = CANVAS_HEIGHT / 2;
private int Sx1 = CANVAS_WIDTH ;
private int Sy1 = CANVAS_HEIGHT ;
private int Sy2 = CANVAS_HEIGHT ;
private int Rx1 = CANVAS_WIDTH - CANVAS_WIDTH;
private int Ry1 = CANVAS_HEIGHT;
private int Rx2 = CANVAS_WIDTH;
private int Ry2 = CANVAS_HEIGHT ;
private int Lx1 = CANVAS_WIDTH / 2;
private int Ly1 = CANVAS_HEIGHT / 2;
private int Lx2 = CANVAS_WIDTH / 2;
private int Ly2 = CANVAS_HEIGHT / 2;
private int Mx1 = CANVAS_WIDTH / 2;
private int My1 = CANVAS_HEIGHT / 2;
private int Mx2 = CANVAS_WIDTH / 2;
private int My2 = CANVAS_HEIGHT / 2;
int[] xs = {380, 460, 460, 540, 540, 620, 500, 380};
int[] ys = {260, 260, 250, 250, 260, 260, 205, 260};
private DrawCanvas canvas;
private JTextField Altitude;
private JTextField TASpeed;
private JLabel altButton;
private int countA = 0;
private int countS = 0;
private int Bcount1 = 0;
public String Ccount = Integer.toString(Bcount1);
public class CountUpAltitude extends AbstractAction {
/** Constructor */
public CountUpAltitude(String name, String shortDesc, Integer mnemonic) {
super(name);
putValue(SHORT_DESCRIPTION, shortDesc);
putValue(MNEMONIC_KEY, KeyEvent.VK_3);
Bcount1 += 1;
}
//RIGHT
@Override
public void actionPerformed(ActionEvent e) {
addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent evt) {
switch(evt.getKeyCode()) {
case KeyEvent.VK_NUMPAD6:
//original count
countA += 5;
Altitude.setText(countA + "");
}
}
});
}
}
public class CountDownAltitude extends AbstractAction {
/** Constructor */
public CountDownAltitude(String name, String shortDesc, Integer mnemonic) {
super(name);
putValue(SHORT_DESCRIPTION, shortDesc);
putValue(MNEMONIC_KEY, KeyEvent.VK_4);
}
//RIGHT
@Override
public void actionPerformed(ActionEvent e) {
addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent evt) {
switch(evt.getKeyCode()) {
case KeyEvent.VK_NUMPAD3:
//original count
countA -= 5;
Altitude.setText(countA + "");
}
}
});
}
}
public class CountUpTASpeed extends AbstractAction {
/** Constructor */
public CountUpTASpeed(String name, String shortDesc, Integer mnemonic) {
super(name);
putValue(SHORT_DESCRIPTION, shortDesc);
putValue(MNEMONIC_KEY, KeyEvent.VK_1);
}
//LEFT
@Override
public void actionPerformed(ActionEvent e) {
addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent evt) {
switch(evt.getKeyCode()) {
case KeyEvent.VK_NUMPAD4:
//original count
countS += 5;
TASpeed.setText(countS + "");
}
}
});
}
}
public class CountDownTASpeed extends AbstractAction {
/** Constructor */
public CountDownTASpeed(String name, String shortDesc, Integer mnemonic) {
super(name);
putValue(SHORT_DESCRIPTION, shortDesc);
putValue(MNEMONIC_KEY, KeyEvent.VK_2);
}
//LEFT
@Override
public void actionPerformed(ActionEvent e) {
addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent evt) {
switch(evt.getKeyCode()) {
case KeyEvent.VK_NUMPAD1:
//original count
countS -= 5;
TASpeed.setText(countS + "");
}
}
});
}
}
public Display() {
canvas = new DrawCanvas();
canvas.setPreferredSize(new Dimension(CANVAS_WIDTH, CANVAS_HEIGHT));
canvas.setLayout(new BorderLayout());
Container cp = getContentPane();
cp.setLayout(new BorderLayout());
// Create the Actions shared by the button and keys
Action countUpAltitude = new CountUpAltitude("Count Up",
"", new Integer(KeyEvent.VK_ENTER));
Action countDownAltitude = new CountDownAltitude("Count Down",
"", new Integer(KeyEvent.VK_D));
Action countUpTASpeed = new CountUpTASpeed("Count Up",
"", new Integer(KeyEvent.VK_ENTER));
Action countDownTASpeed = new CountDownTASpeed("Count Down",
"", new Integer(KeyEvent.VK_D));
Altitude = new JTextField("0", 5);
Altitude.setHorizontalAlignment(JTextField.CENTER);
Altitude.setEditable(false);
Altitude.setOpaque(false);
Altitude.setFont(Altitude.getFont().deriveFont(25f));
TASpeed = new JTextField("0", 5);
TASpeed.setHorizontalAlignment(JTextField.CENTER);
TASpeed.setEditable(false);
TASpeed.setOpaque(false);
TASpeed.setFont(Altitude.getFont().deriveFont(25f));
altButton = new JLabel();
altButton.setText(Ccount);
canvas.add(altButton, BorderLayout.SOUTH);
canvas.add(Altitude, BorderLayout.LINE_END);
canvas.add(TASpeed, BorderLayout.LINE_START);
//Invisible
JButton btnCountUp = new JButton();
btnCountUp.setFocusable(false);
btnCountUp.setHideActionText(true);
// btnCountUp.setContentAreaFilled(false);
// btnCountUp.setBorderPainted(false);
canvas.add(btnCountUp, BorderLayout.NORTH);
//Invisible
JButton btnCountDown = new JButton();
btnCountDown.setFocusable(false);
btnCountDown.setHideActionText(true);
// btnCountDown.setContentAreaFilled(false);
// btnCountDown.setBorderPainted(false);
canvas.add(btnCountDown, BorderLayout.NORTH);
// Set actions for buttons
btnCountUp.setAction(countUpAltitude);
btnCountDown.setAction(countDownAltitude);
JButton btnCountUpS = new JButton();
btnCountUpS.setFocusable(false);
btnCountUpS.setHideActionText(true);
// btnCountUpS.setContentAreaFilled(false);
// btnCountUpS.setBorderPainted(false);
canvas.add(btnCountUpS, BorderLayout.SOUTH);
//Invisible
JButton btnCountDownS = new JButton();
btnCountDownS.setFocusable(false);
btnCountDownS.setHideActionText(true);
// btnCountDownS.setContentAreaFilled(false);
// btnCountDownS.setBorderPainted(false);
canvas.add(btnCountDownS, BorderLayout.SOUTH);
// Set actions for buttons
btnCountUpS.setAction(countUpTASpeed);
btnCountDownS.setAction(countDownTASpeed);
addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent evt) {
switch(evt.getKeyCode()) {
case KeyEvent.VK_LEFT:
Rx1 -= 10; Ry1 += 10;
Rx2 += 10; Ry2 -= 10;
x1 -=10; x2 +=10;
Mx1 += 10; Mx2 -= 10;
repaint();
break;
case KeyEvent.VK_RIGHT:
Rx1 -= 10; Ry1 -= 10;
Rx2 += 10; Ry2 += 10;
x1 += 10; x2 += 10;
Mx1 -= 10; Mx2 += 10;
repaint();
break;
case KeyEvent.VK_DOWN:
y1 -= 10; y2 -= 10;
Ly1 -= 10; Ly2 -= 10;
Sy1 += 10; Sy2 -= 10;
Ry1 +=10; Ry2 += 10;
repaint();
break;
case KeyEvent.VK_UP:
y1 += 10; y2 += 10;
Ly1 += 10; Ly2 += 10;
Sy1 -= 10; Sy2 += 10;
Ry1 -= 10; Ry2 -= 10;
repaint();
break;
case KeyEvent.VK_M:
System.exit(0);
}
}
});
cp.add(canvas, BorderLayout.LINE_START);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setTitle("FLIGHT DISPLAY");
pack();
setVisible(true);
requestFocus();
}
class DrawCanvas extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
setBackground(CANVAS_BACKGROUND);
g.setColor(GROUND_COLOR);
//Draw ground Color
g.drawRect(Sx1 - Sx1,Sy1 /2, CANVAS_WIDTH, Sy2 /2);
g.fillRect(Sx1 - Sx1, Sy1 /2, CANVAS_WIDTH, Sy2 /2);
g.setColor(LINE_COLOR);
//Draw line centre horizontal
g.drawLine(Rx1, Ry1 /2, Rx2, Ry2 /2);
g.drawOval(x1 -15, y1 -15, 30, 30);
g.fillOval(x1 - 5, y1 -5, 10, 10);
//Draw line centre vertical
//Draw line dim
g.setColor(Color.YELLOW);
g.fillArc(300, 0, 400, 140, 0, 180);
g.setColor(LINE_COLOR);
g.drawLine(Lx1 -25, Ly1 +20, Lx2 +25, Ly2 +20);
g.drawLine(Lx1 -50, Ly1 +40, Lx2 +50, Ly2 +40);
g.drawLine(Lx1 -25, Ly1 +60, Lx2 +25, Ly2 +60);
g.drawLine(Lx1 -75, Ly1 +80, Lx2 +75, Ly2 +80);
g.drawLine(Lx1 -25, Ly1 +100, Lx2 +25, Ly2 +100);
//Draw line dim
g.drawLine(Lx1 -25, Ly1 -20, Lx2 +25, Ly2 -20);
g.drawLine(Lx1 -50, Ly1 -40, Lx2 +50, Ly2 -40);
g.drawLine(Lx1 -25, Ly1 -60, Lx2 +25, Ly2 -60);
g.drawLine(Lx1 -75, Ly1 -80, Lx2 +75, Ly2 -80);
g.drawLine(Lx1 -25, Ly1 -100, Lx2 +25, Ly2 -100);
//Draw polyline centre plane
g.drawPolyline(xs, ys, 8);
g.setColor(Color.BLACK);
g.drawArc(300, 0, 400, 140, 0, 180);
g.drawLine(Mx1+30, My1 + My1, Mx2, My2 - My2);
g.drawLine(Mx1-30, My1 + My1, Mx2, My2 - My2);
g.drawLine(Mx1, My1 + My1, Mx2, My2 - My2);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new Display();
}
});
}
}
答案 0 :(得分：2)
KeyEvent.VK_2只是标准美国键盘上非小键盘区域中的数字2的键。
public static final int VK_2 = 0x32;
以下代码对我来说很好，我不希望你没有为这个键添加一个开关盒，所以你可以做一个小测试来打印所需键的ASCII值并找出它实际对应的内容到KeyEvent类。
public void keyPressed(KeyEvent e) {
switch (e.getKeyCode()) {
case KeyEvent.VK_2:
System.out.println("Non Numpad 2");
case KeyEvent.VK_NUMPAD3:
System.out.println("NumPad 3");
}
}