Using a TextField - Java SE 6

You can control whether the contents of a text field may be modified by the user by

calling setEditable( ). You can determine editability by calling isEditable( ). These methods

are shown here:

boolean isEditable( )

void setEditable(boolean canEdit)

isEditable( ) returns true if the text may be changed and false if not. In setEditable( ), if

canEdit is true, the text may be changed. If it is false, the text cannot be altered.

There may be times when you will want the user to enter text that is not displayed, such

as a password. You can disable the echoing of the characters as they are typed by calling

setEchoChar( ). This method specifies a single character that the TextField will display when

characters are entered (thus, the actual characters typed will not be shown). You can check a

text field to see if it is in this mode with the echoCharIsSet( ) method. You can retrieve the

echo character by calling the getEchoChar( ) method. These methods are as follows:

void setEchoChar(char ch)

boolean echoCharIsSet( )

char getEchoChar( )

Here, ch specifies the character to be echoed.

Handling a TextField

Since text fields perform their own editing functions, your program generally will not

respond to individual key events that occur within a text field. However, you may want

to respond when the user presses ENTER. When this occurs, an action event is generated.

Here is an example that creates the classic user name and password screen:

// Demonstrate text field.

import java.awt.*;

import java.awt.event.*;

import java.applet.*;

</applet>

public class TextFieldDemo extends Applet

implements ActionListener {

TextField name, pass;

public void init() {

Label namep = new Label("Name: ", Label.RIGHT);

Label passp = new Label("Password: ", Label.RIGHT);

name = new TextField(12);

pass = new TextField(8);

pass.setEchoChar('?');

add(namep);

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