书上有个小项目 说是在一定时间输入一定数量的字符串 ...我想把输入的字符串改成箭头↑ ↓ ← →
但是我在键盘上按下这些键时 怎么判断我输入的是什么 . 该怎么实现 ?
这个 只是我看书上的例子后有这个想法. 不知道怎么做了 ..
------解决方案--------------------
这里给你贴一个具体的实例，但是还有点小问题就是 左箭头的具体实现要再用程序控制光标
- Java code
import javax.swing.*;import java.awt.event.KeyListener;import java.awt.event.KeyEvent;public class KeyListenerFrame extends JFrame implements KeyListener { private JTextArea jta=new JTextArea(10,10); public KeyListenerFrame(String title){ super(title); jta.addKeyListener(this); this.getContentPane().add(jta); this.pack(); this.setVisible(true); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.setLocationRelativeTo(null); } public static void main(String[] args) { new KeyListenerFrame("demo"); } @Override public void keyTyped(KeyEvent e) { //To change body of implemented methods use File | Settings | File Templates.// if(e.getKeyCode()==KeyEvent.VK_DOWN){// jta.append("↓");// } } @Override public void keyPressed(KeyEvent e) { switch(e.getKeyCode()){ case KeyEvent.VK_DOWN: jta.append("↓"); break; case KeyEvent.VK_UP: jta.append("↑"); break; case KeyEvent.VK_LEFT: jta.append("←"); break; case KeyEvent.VK_RIGHT: jta.append("→"); break;// default:// jta.append(""+e.getKeyChar()); } } @Override public void keyReleased(KeyEvent e) { //To change body of implemented methods use File | Settings | File Templates. }}
------解决方案--------------------
这里给你贴一个具体的实例，但是还有点小问题就是 左箭头的具体实现要再用程序控制光标
- Java code
import javax.swing.*;import java.awt.event.KeyListener;import java.awt.event.KeyEvent;public class KeyListenerFrame extends JFrame implements KeyListener { private JTextArea jta=new JTextArea(10,10); public KeyListenerFrame(String title){ super(title); jta.addKeyListener(this); this.getContentPane().add(jta); this.pack(); this.setVisible(true); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.setLocationRelativeTo(null); } public static void main(String[] args) { new KeyListenerFrame("demo"); } @Override public void keyTyped(KeyEvent e) { //To change body of implemented methods use File | Settings | File Templates.// if(e.getKeyCode()==KeyEvent.VK_DOWN){// jta.append("↓");// } } @Override public void keyPressed(KeyEvent e) { switch(e.getKeyCode()){ case KeyEvent.VK_DOWN: jta.append("↓"); break; case KeyEvent.VK_UP: jta.append("↑"); break; case KeyEvent.VK_LEFT: jta.append("←"); break; case KeyEvent.VK_RIGHT: jta.append("→"); break;// default:// jta.append(""+e.getKeyChar()); } } @Override public void keyReleased(KeyEvent e) { //To change body of implemented methods use File | Settings | File Templates. }}