 |
Chapter 19 java.awt Reference |
 |
TextField
Name
TextField
![[Graphic: Figure from the text]](./figs/textfi2.gif)
Description
The TextField class provides a single line Component for user input.
Class Definition
public class java.awt.TextField
extends java.awt.TextComponent {
// Constructors
public TextField();
public TextField (int columns);
public TextField (String text);
public TextField (String text, int columns);
// Instance Methods
public void addActionListener (ActionListener l); 
public void addNotify();
public boolean echoCharIsSet();
public int getColumns();
public char getEchoChar();
public Dimension getMinimumSize();
public Dimension getMinimumSize (int columns);
public Dimension getPreferredSize();
public Dimension getPreferredSize (int columns);
public Dimension minimumSize(); 
public Dimension minimumSize (int columns);
public Dimension preferredSize();
public Dimension preferredSize (int columns);
public void removeActionListener (ActionListener l);
public void setColumns(int columns);
public void setEchoChar(char c);
public void setEchoCharacter (char c);
// Protected Instance Methods
protected String paramString();
protected void processActionEvent (ActionEvent e);
protected void processEvent (AWTEvent e);
}
Constructors
TextField
public TextField()
- Description
-
Constructs a TextField object of the default size.
public TextField (int columns)
- Parameters
-
- columns
-
Requested number of displayed columns.
- columns
- Description
-
Constructs a TextField object of the given size.
public TextField (String text)
- Parameters
-
- text
-
Initial text for TextField.
- text
- Description
-
Constructs a TextField object with the given content.
public TextField (String text, int columns)
- Parameters
-
- text
-
Initial text for TextField.
- columns
-
Requested number of displayed columns.
- text
- Description
-
Constructs a TextField object with the given content and size.
Instance Methods
addActionListener
public void addActionListener (ActionListener l)
- Parameters
-
- l
-
An object that implements the ActionListener interface.
- l
- Description
-
Add a listener for the action event.
addNotify
public synchronized void addNotify()
- Overrides
-
Component.addNotify()
- Description
-
Creates TextField's peer.
echoCharIsSet
public boolean echoCharIsSet()
- Returns
-
true if the TextField has an echo character used as a response to any input character; false otherwise. An echo character can be used to create a TextField for hidden input, like a password; the same character (e.g., "x") is used to echo all input.
getColumns
public int getColumns()
- Returns
-
The width of the TextField in columns.
getEchoChar
public char getEchoChar()
- Returns
-
The current echo character.
getMinimumSize
public Dimension getMinimumSize()
- Returns
-
The minimum dimensions of the TextField.
public Dimension getMinimumSize (int columns)
- Parameters
-
- columns
-
Number of columns within TextField to size.
- columns
- Returns
-
The minimum dimensions of a TextField of the given size.
getPreferredSize
public Dimension getPreferredSize()
- Returns
-
The preferred dimensions of the TextField.
public Dimension getPreferredSize (int columns)
- Parameters
-
- columns
-
Number of columns within TextField to size.
- columns
- Returns
-
The preferred dimensions of a TextField of the given size.
minimumSize
public Dimension minimumSize()
- Returns
-
The minimum dimensions of the TextField. Replaced by getMinimumSize().
public Dimension minimumSize (int columns)
- Parameters
-
- columns
-
Number of columns within TextField to size.
- columns
- Returns
-
The minimum dimensions of a TextField of the given size. Replaced by getMinimumSize(int).
preferredSize
public Dimension preferredSize()
- Returns
-
The preferred dimensions of the TextField. Replaced by getPreferredSize().
public Dimension preferredSize (int columns)
- Parameters
-
- columns
-
Number of columns within TextField to size.
- columns
- Returns
-
The preferred dimensions of a TextField of the given size. Replaced by getPreferredSize(int).
removeActionListener
public void removeActionListener (ActionListener l)
- Parameters
-
- l
-
One of this TextField's ActionListeners.
- l
- Description
-
Remove an action event listener.
setColumns
public void setColumns (int columns)
- Parameters
-
- columns
-
New number of columns.
- columns
- Throws
-
- IllegalArgumentException
-
If columns is less than zero.
- IllegalArgumentException
- Description
-
Changes the number of columns.
setEchoChar
public void setEchoChar (char c)
- Parameters
-
- c
-
The character to echo for all input. To echo the characters that the user types (the default), set the echo character to 0 (zero).
- c
- Description
-
Changes the character that is used to echo all user input in the TextField.
setEchoCharacter
public void setEchoCharacter (char c)
- Parameters
-
- c
-
The character to echo for all input. To echo the characters that the user types (the default), set the echo character to 0 (zero).
- c
- Description
-
Replaced by setEchoChar(char) for consistency with getEchoChar().
Protected Instance Methods
paramString
protected String paramString()
- Returns
-
String with current settings of TextField.
- Overrides
-
TextComponent.paramString()
- Description
-
Helper method for toString() to generate string of current settings.
processActionEvent
protected void processActionEvent (ActionEvent e)
- Parameters
-
- e
-
The action event to process.
- e
- Description
-
Action events are passed to this method for processing. Normally, this method is called by processEvent().
processEvent
protected void processEvent (AWTEvent e)
- Parameters
-
- e
-
The event to process.
- e
- Description
-
Low-level AWTEvents are passed to this method for processing.
See Also
Dimension, TextComponent, String
|
 |
|
| TextComponent |  |
Toolkit |
