Chapter 19
java.awt Reference

TextArea

Name

TextArea

[Graphic: Figure from the text]

Description

The TextArea class provides a multi-line Component for textual user input.

Class Definition

public class java.awt.TextArea
    extends java.awt.TextComponent {
  // Constants
  public final static int SCROLLBARS_BOTH; 
  public final static int SCROLLBARS_HORIZONTAL_ONLY; 
  public final static int SCROLLBARS_NONE; 
  public final static int SCROLLBARS_VERTICAL_ONLY; 
  
  // Constructors
  public TextArea();
  public TextArea (int rows, int columns);
  public TextArea (String text);
  public TextArea (String text, int rows, int columns);
  public TextArea (String text, int rows, int columns, int scrollbars); 
  
  // Instance Methods
  public void addNotify();
  public synchronized void append (String string); 
  public void appendText (String string); 
  public int getColumns();
  public Dimension getMinimumSize(); 
  public Dimension getMinimumSize (int rows, int columns); 
  public Dimension getPreferredSize();    
  public Dimension getPreferredSize (int rows, int columns); 
  public int getRows();
  public int getScrollbarVisibility(); 
  public synchronized void insert (String string, int position); 
  public void insertText (String string, int position); 
  public Dimension minimumSize(); 
  public Dimension minimumSize (int rows, int columns); 
  public Dimension preferredSize(); 
  public Dimension preferredSize (int rows, int columns); 
  public synchronized void replaceRange (String str, int start, int end); 
  public void replaceText (String string, int startPosition, int endPosition); 
  public void setColumns (int columns); 
  public void setRows (int rows); 
  
  // Protected Instance Methods
  protected String paramString();
}

Constants

SCROLLBARS_BOTH

public final static int SCROLLBARS_BOTH

Show both the horizontal and vertical scrollbars.

SCROLLBARS_HORIZONTAL_ONLY

public final static int SCROLLBARS_HORIZONTAL_ONLY

Show the horizontal scrollbar.

SCROLLBARS_NONE

public final static int SCROLLBARS_NONE

Show no scrollbars.

SCROLLBARS_VERTICAL_ONLY

public final static int SCROLLBARS_VERTICAL_ONLY

Show the vertical scrollbar.

Constructors

TextArea

public TextArea()

Description: Constructs a TextArea object with the default size and no initial content. The default size of a text area varies widely from platform to platform, so it's best to avoid this constructor.

public TextArea (int rows, int columns)

Parameters

rows

Requested number of displayed rows.

columns

Requested number of displayed columns.

Description

Constructs a TextArea object of the given size and no initial content.

public TextArea (String text)

Parameters

text: Initial text for TextArea.

Description

Constructs a TextArea object with the given initial content.

public TextArea (String text, int rows, int columns)

Parameters

text

Initial text for TextArea.

rows

Requested number of displayed rows.

columns

Requested number of displayed columns.

Description

Constructs a TextArea object with the given content and size.

public TextArea (String text, int rows, int columns, int scrollbars)

Parameters

text

Initial text for TextArea.

rows

Requested number of displayed rows.

columns

Requested number of displayed columns.

scrollbars

Requested scrollbar visibility. Use one of the constants defined.

Description

Constructs a TextArea object with the given content, size, and scrollbar visibility.

Instance Methods

addNotify

public void addNotify()

Overrides

Component.addNotify()

Description

Creates TextArea's peer.

append

public synchronized void append (String string)

Parameters

string: Content to append to the end of the TextArea.

Description

Appends the given text string to the text already displayed in the TextArea.

appendText

public void appendText (String string)

Parameters

string: Content to append to end of TextArea.

Description

Replaced by append(String).

getColumns

public int getColumns()

Returns: The width of the TextArea in columns.

getMinimumSize

public Dimension getMinimumSize()

Returns: The minimum dimensions of the TextArea.

public Dimension getMinimumSize (int rows, int columns)

Parameters

rows

Number of rows within TextArea to size.

columns

Number of columns within TextArea to size.

Returns

The minimum dimensions of a TextArea of the given size.

getPreferredSize

public Dimension getPreferredSize()

Returns: The preferred dimensions of the TextArea.

public Dimension getPreferredSize (int rows, int columns)

Parameters

rows

Number of rows within TextArea to size.

columns

Number of columns within TextArea to size.

Returns

The preferred dimensions of a TextArea of the given size.

getRows

public int getRows()

Returns: The height of the TextArea in rows.

getScrollbarVisibility

public int getScrollbarVisibility()

Returns: One of the SCROLLBAR_ constants indicating which scrollbars are visible.

insert

public synchronized void insert (String string, int position)

Parameters

string

Content to place within TextArea content.

position

Location to insert content.

Description

Places additional text within the TextArea at the given position.

insertText

public void insertText (String string, int position)

Parameters

string

Content to place within TextArea content.

position

Location to insert content.

Description

Places additional text within the TextArea at the given position. Replaced by insert(String, int).

minimumSize

public Dimension minimumSize()

Returns: The minimum dimensions of the TextArea. Replaced by getMinimumSize().

public Dimension minimumSize (int rows, int columns)

Parameters

rows

Number of rows within TextArea to size.

columns

Number of columns within TextArea to size.

Returns

The minimum dimensions of a TextArea of the given size. Replaced by getMinimumSize(int, int).

preferredSize

public Dimension preferredSize()

Returns: The preferred dimensions of the TextArea. Replaced by getPreferredSize().

public Dimension preferredSize (int rows, int columns)

Parameters

rows

Number of rows within TextArea to size.

columns

Number of columns within TextArea to size.

Returns

The preferred dimensions of a TextArea of the given size. Replaced by getPreferredSize(int, int).

replaceRange

public synchronized void replaceRange (String str, int start, int end)

Parameters

str

New content to place in TextArea.

start

Starting position of content to replace.

end

Ending position of content to replace.

Description

Replaces a portion of the TextArea's content with the given text.

replaceText

public void replaceText (String string, int startPosition, int endPosition)

Parameters

string

New content to place in TextArea.

startPosition

Starting position of content to replace.

endPosition

Ending position of content to replace.

Description

Replaces a portion of the TextArea's content with the given text. Replaced by replaceRange(String, int, int).

setColumns

public void setColumns (int columns)

Parameters

columns: New number of columns.

Throws

IllegalArgumentException: If columns is less than zero.

Description

Changes the number of columns.

setRows

public void setRows (int rows)

Parameters

rows: New number of columns.

Throws

IllegalArgumentException: If rows is less than zero.

Description

Changes the number of rows.

Protected Instance Methods

paramString

protected String paramString()

Returns

String with current settings of TextArea.

Overrides

TextComponent.paramString()

Description

Helper method for toString() to generate string of current settings.