Java language program design three

Design topic

This program is to display the character JTextField object corresponding to the user button to display characters. When you press a certain alphanumeric key, a keyboard event is generated. The keyboard event is handled by the keyTyped method. Before displaying the user button, remove the previous character in the JTYPEFIELD object --- Programs only display only one character at a time, The character corresponds to the button, in the homepage program, the font of the character is set to Chinese_GB2312, the color random change of characters, because the Keylistener interface contains three methods, and only one method of implementation in a program, Use an anonymous mechanism to register a listener object.

Note: When the keyboard occurs, the operation method to be performed is specified below. The Keylistener interface consists of three: keypressed, keyreleased, keytyped.

When a META key (such as Control, Shift, Alt) is pressed, KeyPressed; execute the keytyped when pressing the letter; KEYRELEASED is executed when the selected is released.

Import java.awt. *;

Import java.awt.event. *;

Import javax.swing. *;

Public class onechar extends japplet {

Jtextfield ONELETER = New JtextField (1);

Public void init () {

Container C = getContentPane ();

Onletter.addKeylistener (New KeyAdapter () {

Public void keytyped (KeyEvent E) {

Float Red, Green, Blue;

Color FG, BG;

Onletter.SetText ("");

RED = (float) math.random ();

Green = (float) math.random ();

Blue = (float) math.random ();

FG = New Color (Red, Green, Blue);

BG = color.white;

Onletter.SetForeground (FG);

Onletter.SetBackground (BG);

Onletter.SetCaretcolor (BG);

ONELETTER.SETFONT (New Font ("Courior", Font.Bold, 200);

}

});

C.SetLayout (New GridLayout (1, 1));

C.SetBackground (color.white);

C.ADD (ONELETTER);

JOPTIONPANE.SHOWMESSAGEDIALOG (NULL, "CLINK ON The applet;" information ", JOPANE.PLAIN_MESSAGE

}

}

HTML is described as follows: