Java know how much (94) keyboard events

Event sources for keyboard events are typically hack component related, and keyboard events occur when a component is activated, pressing, releasing, or tapping a key on the keyboard. The interface for keyboard events is KeyListener, and the method to register the keyboard event monitor is Addkeylistener (monitor). There are 3 implementations of the KeyListener interface:

• keypressed (KeyEvent E): A key on the keyboard is pressed;
• keyreleased (KeyEvent E): A key on the keyboard is pressed and released;
• keytyped (KeyEvent e): A combination of two methods for keypressed and keyreleased.

The class that manages keyboard events is KeyEvent, which provides methods:
public int getKeyCode (), gets the key code that is pressed, the key table is defined in the KeyEvent class, see appendix.

The "Example 11-20" applet has a button and a text area, which acts as the source of the event where the keyboard event occurred and monitors it. When the program runs, click the button first to activate the button. When you enter an English letter later, the input letter is displayed in the body area. When the letters are displayed, the letters are separated by a space character and are filled with 10 letters, and the lines are displayed.

1 Importjava.applet.*2 Importjava.awt.*;3 Importjava.awt.event.*;4  Public classExample6_10extendsAppletImplementskeylistener{5     intCount =0;6Button Button =NewButton ();7TextArea Text =NewTextArea (5,20);8      Public voidinit () {9Button.addkeylistener ( This);Ten Add (button); Add (text); One     } A      Public voidkeypressed (KeyEvent e) { -         intt =E.getkeycode (); -         if(t>=keyevent.vk_a&&t<=keyevent.vk_z) { theText.append ((Char) t+ ""); -count++; -             if(count%10==0) -Text.append ("\ n"); +         } -     } +      Public voidkeytyped (KeyEvent e) {} A      Public voidkeyreleased (KeyEvent e) {} at}

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Java know how much (94) keyboard events