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Java AWT

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Component

Name

Component

[Graphic: Figure from the text]

Description

The Component class is the parent of all non-menu GUI components.

Class Definition

public abstract class java.awt.Component
    extends java.lang.Object
    implements java.awt.image.ImageObserver
    implements java.awt.MenuContainer
    implements java.io.Serializable {
  // Constants
  public final static float BOTTOM_ALIGNMENT; (New)
  public final static float CENTER_ALIGNMENT; (New)
  public final static float LEFT_ALIGNMENT; (New)
  public final static float RIGHT_ALIGNMENT; (New)
  public final static float TOP_ALIGNMENT; (New)
  // Variables
  protected Locale locale; (New)
  // Constructors
  protected Component(); (New)
  
  // Instance Methods
  public boolean action (Event e, Object o); (Deprecated)
  public synchronized void add (PopupMenu popup); (New)
  public synchronized void addComponentListener 
      (ComponentListener l); (New)
  public synchronized void addFocusListener (FocusListener l); (New)
  public synchronized void addKeyListener (KeyListener l); (New)
  public synchronized void addMouseListener (MouseListener l); (New)
  public synchronized void addMouseMotionListener 
      (MouseMotionListener l); (New)
  public void addNotify();
  public Rectangle bounds(); (Deprecated)
  public int checkImage (Image image, ImageObserver observer);
  public int checkImage (Image image, int width, int height, 
      ImageObserver observer);
  public boolean contains (int x, int y); (New)
  public boolean contains (Point p); (New)
  public Image createImage (ImageProducer producer);
  public Image createImage (int width, int height);
  public void deliverEvent (Event e); (Deprecated)
  public void disable(); (Deprecated)
  public final void dispatchEvent (AWTEvent e) (New)
  public void doLayout(); (New)
  public void enable(); (Deprecated)
  public void enable (boolean condition); (Deprecated)
  public float getAlignmentX(); (New)
  public float getAlignmentY(); (New)
  public Color getBackground();
  public Rectangle getBounds(); (New)
  public synchronized ColorModel getColorModel();
  public Component getComponentAt (int x, int y); (New)
  public Component getComponentAt (Point p); (New)
  public Cursor getCursor(); (New)
  public Font getFont();
  public FontMetrics getFontMetrics (Font f);
  public Color getForeground();
  public Graphics getGraphics();
  public Locale getLocale(); (New)
  public Point getLocation(); (New)
  public Point getLocationOnScreen(); (New)
  public Dimension getMaximumSize(); (New)
  public Dimension getMinimumSize(); (New)
  public String getName(); (New)
  public Container getParent();
  public ComponentPeer getPeer(); (Deprecated)
  public Dimension getPreferredSize(); (New)
  public Dimension getSize(); (New)
  public Toolkit getToolkit();
  public final Object getTreeLock(); (New)
  public boolean gotFocus (Event e, Object o); (Deprecated)
  public boolean handleEvent (Event e); (Deprecated)
  public void hide(); (Deprecated)
  public boolean imageUpdate (Image image, int infoflags, int x, int y, 
      int width, int height);
  public boolean inside (int x, int y); (Deprecated)
  public void invalidate();
  public boolean isEnabled();
  public boolean isFocusTraversable(); (New)
  public boolean isShowing();
  public boolean isValid();
  public boolean isVisible();
  public boolean keyDown (Event e, int key); (Deprecated)
  public boolean keyUp (Event e, int key); (Deprecated)
  public void layout(); (Deprecated)
  public void list();
  public void list (PrintStream out);
  public void list (PrintStream out, int indentation);
  public void list (PrintWriter out); (New)
  public void list (PrintWriter out, int indentation); (New)
  public Component locate (int x, int y); (Deprecated)
  public Point location(); (Deprecated)
  public boolean lostFocus (Event e, Object o); (Deprecated)
  public Dimension minimumSize(); (Deprecated)
  public boolean mouseDown (Event e, int x, int y); (Deprecated)
  public boolean mouseDrag (Event e, int x, int y); (Deprecated)
  public boolean mouseEnter (Event e, int x, int y); (Deprecated)
  public boolean mouseExit (Event e, int x, int y); (Deprecated)
  public boolean mouseMove (Event e, int x, int y); (Deprecated)
  public boolean mouseUp (Event e, int x, int y); (Deprecated)
  public void move (int x, int y); (Deprecated)
  public void nextFocus(); (Deprecated)
  public void paint (Graphics g);
  public void paintAll (Graphics g);
  public boolean postEvent (Event e); (Deprecated)
  public Dimension preferredSize(); (Deprecated)
  public boolean prepareImage (Image image, ImageObserver observer);
  public boolean prepareImage (Image image, int width, int height, 
      ImageObserver observer);
  public void print (Graphics g);
  public void printAll (Graphics g);
  public synchronized void remove (MenuComponent popup); (New)
  public synchronized void removeComponentListener 
      (ComponentListener l); (New)
  public synchronized void removeFocusListener (FocusListener l); (New)
  public synchronized void removeKeyListener (KeyListener l); (New)
  public synchronized void removeMouseListener (MouseListener l); (New)
  public synchronized void removeMouseMotionListener 
      (MouseMotionListener l); (New)
  public void removeNotify();
  public void repaint();
  public void repaint (long tm);
  public void repaint (int x, int y, int width, int height);
  public void repaint (long tm, int x, int y, int width, int height);
  public void requestFocus();
  public void reshape (int x, int y, int width, int height); (Deprecated)
  public void resize (Dimension d); (Deprecated)
  public void resize (int width, int height); (Deprecated)
  public void setBackground (Color c);
  public void setBounds (int x, int y, int width, int height); (New)
  public void setBounds (Rectangle r); (New)
  public synchronized void setCursor (Cursor cursor); (New)
  public void setEnabled (boolean b); (New)
  public synchronized void setFont (Font f);
  public void setForeground (Color c);
  public void setLocale (Locale l); (New)
  public void setLocation (int x, int y); (New)
  public void setLocation (Point p); (New)
  public void setName (String name); (New)
  public void setSize (int width, int height); (New)
  public void setSize (Dimension d); (New)
  public void setVisible (boolean b); (New)
  public void show(); (Deprecated)
  public void show (boolean condition); (Deprecated)
  public Dimension size(); (Deprecated)
  public String toString();
  public void transferFocus(); (New)
  public void update (Graphics g);
  public void validate();
  
  // Protected Instance Methods
  protected final void disableEvents (long eventsToDisable); (New)
  protected final void enableEvents (long eventsToEnable); (New)
  protected String paramString();
  protected void processComponentEvent (ComponentEvent e); (New)
  protected void processEvent (AWTEvent e); (New)
  protected void processFocusEvent (FocusEvent e); (New)
  protected void processKeyEvent (KeyEvent e); (New)
  protected void processMouseEvent (MouseEvent e); (New)
  protected void processMouseMotionEvent (MouseEvent e); (New)
}

Constants

BOTTOM_ALIGNMENT

public final static float BOTTOM_ALIGNMENT (New)

Constant representing bottom alignment in getAlignmentY().

CENTER_ALIGNMENT

public final static float CENTER_ALIGNMENT (New)

Constant representing center alignment in getAlignmentX() and getAlignmentY().

LEFT_ALIGNMENT

public final static float LEFT_ALIGNMENT (New)

Constant representing left alignment in getAlignmentX().

RIGHT_ALIGNMENT

public final static float RIGHT_ALIGNMENT (New)

Constant representing right alignment in getAlignmentX().

TOP_ALIGNMENT

public final static float TOP_ALIGNMENT (New)

Constant representing top alignment in getAlignmentY().

Variables

locale

protected Locale locale (New)

Description

The locale for the component. Used for internationalization support.

Constructors

Component

protected Component() (New)

Description

This constructor creates a "lightweight" component. This constructor allows Component to be directly subclassed using code written entirely in Java.

Instance Methods

action

public boolean action (Event e, Object o) (Deprecated)

Parameters

e

Event instance identifying what triggered the call to this method.

o

Argument specific to the component subclass that generated the event.

Returns

true if event handled, false to propagate it to parent container.

Description

Method called when user performs some action in Component. This method is a relic of the old 1.0.2 event model and is replaced by the process...Event() methods.

add

public synchronized void add (PopupMenu popup) (New)

Parameters

popup

The menu to add.

Description

After the PopupMenu is added to a component, it can be shown in the component's coordinate space.

addComponentListener

public void addComponentListener (ComponentListener l) (New)

Description

Adds a listener for the ComponentEvent objects this Component generates.

addFocusListener

public void addFocusListener (FocusListener l) (New)

Description

Adds a listener for the FocusEvent objects this Component generates.

addKeyListener

public void addKeyListener (KeyListener l) (New)

Description

Adds a listener for the KeyEvent objects this Component generates.

addMouseListener

public void addMouseListener (MouseListener l) (New)

Description

Adds a listener for the MouseEvent objects this Component generates.

addMouseMotionListener

public void addMouseMotionListener (MouseMotionListener l) (New)

Description

Adds a listener for the motion MouseEvent objects this Component generates.

addNotify

public void addNotify()

Description

Creates peer of Component's subclass.

bounds

public Rectangle bounds() (Deprecated)

Returns

Gets bounding rectangle of Component.

Description

A Rectangle that returns the outer limits of the Component. Replaced by getBounds() in 1.1.

checkImage

public int checkImage (Image image, ImageObserver observer)

Parameters

image

Image to check.

observer

The object an image will be rendered onto.

Returns

ImageObserver Flags ORed together indicating the image's status.

Description

Checks status of image construction.

public int checkImage (Image image, int width, int height, ImageObserver observer)

Parameters

image

Image to check.

width

Horizontal size image will be scaled to.

height

Vertical size image will be scaled to.

observer

Object image will be rendered onto.

Returns

ImageObserver flags ORed together indicating the image's status.

Description

Checks status of image construction.

contains

public boolean contains (int x, int y) (New)

Parameters

x

The x coordinate, in this Component's coordinate system.

y

The y coordinate, in this Component's coordinate system.

Returns

true if the Component contains the point; false otherwise.

public boolean contains (Point p) (New)

Parameters

p

The point to be tested, in this Component's coordinate system.

Returns

true if the Component contains the point; false otherwise.

createImage

public Image createImage (ImageProducer producer)

Parameters

producer

Class that implements ImageProducer interface to create the new image.

Returns

Newly created image instance.

Description

Creates an Image based upon an ImageProducer.

public Image createImage (int width, int height)

Parameters

width

Horizontal size for in-memory Image.

height

Vertical size for in-memory Image.

Returns

Newly created image instance.

Description

Creates an empty in-memory Image for double buffering; to draw on the image, use its graphics context.

deliverEvent

public void deliverEvent (Event e) (Deprecated)

Parameters

e

Event instance to deliver.

Description

Delivers event to the component for processing.

disable

public void disable() (Deprecated)

Description

Disables component so that it is unresponsive to user interactions. Replaced by setEnabled(false).

dispatchEvent

public final void dispatchEvent (AWTEvent e) (New)

Parameters

e

The AWTEvent to process.

Description

Tells the component to deal with the AWTEvent e.

doLayout

public void doLayout() (New)

Description

Lays out component. This method is a replacement for layout().

enable

public void enable() (Deprecated)

Description

Enables component so that it is responsive to user interactions. Use setEnabled(true) instead.

public void enable (boolean condition) (Deprecated)

Parameters

condition

true to enable the component; false to disable it.

Description

Enables or disables the component based upon condition. Use setEnabled(boolean) instead.

getAlignmentX

public float getAlignmentX() (New)

Returns

A number between 0 and 1 representing the horizontal alignment of this component.

Description

One of the constants LEFT_ALIGNMENT, CENTER_ALIGNMENT, or RIGHT_ALIGNMENT may be returned. CENTER_ALIGNMENT is returned by default.

getAlignmentY

public float getAlignmentY() (New)

Returns

A number between 0 and 1 representing the vertical alignment of this component.

Description

One of the constants TOP_ALIGNMENT, CENTER_ALIGNMENT, or BOTTOM_ALIGNMENT may be returned. CENTER_ALIGNMENT is returned by default.

getBackground

public Color getBackground()

Returns

Background color of the component.

getBounds

public Rectangle getBounds() (New)

Returns

Gets bounding rectangle of Component.

Description

Returns a Rectangle that returns the outer limits of the Component.

getColorModel

public synchronized ColorModel getColorModel()

Returns

ColorModel used to display the current component.

getComponentAt

public Component getComponentAt (int x, int y) (New)

Parameters

x

The x coordinate, in this Component's coordinate system.

y

The y coordinate, in this Component's coordinate system.

Returns

Returns the Component containing the given point.

public Component getComponentAt (Point p) (New)

Parameters

p

The point to be tested, in this Component's coordinate system.

Returns

Returns the Component containing the given point.

getCursor

public Cursor getCursor() (New)

Returns

Current cursor of the component.

getFont

public Font getFont()

Returns

Current font of the component.

getFontMetrics

public FontMetrics getFontMetrics (Font f)

Parameters

f

A Font object, whose platform specific information is desired.

Returns

Size information for the given Font.

getForeground

public Color getForeground()

Returns

Foreground color of component.

getGraphics

public Graphics getGraphics()

Throws

InternalException

If acquiring graphics context is unsupported.

Returns

Component's graphics context.

getLocale

public Locale getLocale() (New)

Throws

IllegalComponentStateException

If the component does not have a locale or it has not been added to a hierarchy that does.

Returns

Component's locale.

getLocation

public Point getLocation() (New)

Returns

Position of component.

Description

Gets the current position of this Component in its parent's coordinate space.

getLocationOnScreen

public Point getLocationOnScreen() (New)

Returns

Position of component.

Description

Gets the current position of this Component in the screen's coordinate space.

getMaximumSize

public Dimension getMaximumSize() (New)

Returns

The maximum dimensions of the component.

Description

By default, a maximal Dimension is returned.

getMinimumSize

public Dimension getMinimumSize() (New)

Returns

The minimum dimensions of the component.

getName

public String getName() (New)

Returns

This component's name.

getParent

public Container getParent()

Returns

Parent Container of Component.

Description

Gets container that this Component is held in.

getPeer

public ComponentPeer getPeer() (Deprecated)

Returns

Peer of Component.

getPreferredSize

public Dimension getPreferredSize() (New)

Returns

The preferred dimensions of the component.

getSize

public Dimension getSize() (New)

Returns

Dimensions of component.

Description

Gets width and height of component.

getToolkit

public Toolkit getToolkit()

Returns

Toolkit of Component.

getTreeLock

public final Object getTreeLock() (New)

Returns

The AWT tree locking object.

Description

Returns the object used for tree locking and layout operations.

gotFocus

public boolean gotFocus (Event e, Object o) (Deprecated)

Parameters

e

Event instance identifying what triggered the call to this method.

o

Argument specific to the component subclass that generated the event.

Returns

true if event handled, false to propagate it to parent container.

Description

Called when Component gets input focus. This method is not used in the 1.1 event model.

handleEvent

public boolean handleEvent (Event e) (Deprecated)

Parameters

e

Event instance identifying what triggered the call to this method.

Returns

true if event handled, false to propagate it to parent container.

Description

High-level event handling routine that calls helper routines. Replaced by processEvent(AWTEvent).

hide

public void hide() (Deprecated)

Description

Hides component from view. Replaced by setVisible(false).

imageUpdate

public boolean imageUpdate (Image image, int infoflags, int x, int y, int width, int height)

Parameters

image

Image being loaded.

infoflags

ImageObserver flags ORed together of available information.

x

x coordinate of upper-left corner of Image.

y

y coordinate of upper-left corner of Image.

width

Horizontal dimension of Image.

height

Vertical dimension of Image.

Returns

true if Image fully loaded, false otherwise.

Implements

ImageObserver.imageUpdate()

Description

An asynchronous update interface for receiving notifications about Image information as it is loaded. Meaning of parameters changes with values of flags.

inside

public boolean inside (int x, int y) (Deprecated)

Parameters

x

Horizontal position.

y

Vertical position.

Returns

true if the point (x, y) falls within the component's bounds, false otherwise.

Description

Checks if coordinates are within bounding box of Component. Replaced by contains(int, int).

invalidate

public void invalidate()

Description

Sets the component's valid state to false.

isEnabled

public boolean isEnabled()

Returns

true if enabled, false otherwise.

Description

Checks to see if the Component is currently enabled.

isFocusTraversable

public boolean isFocusTraversable() (New)

Returns

true if this Component can be traversed using Tab and Shift-Tab, false otherwise.

Description

Checks to see if the Component is navigable using the keyboard.

isShowing

public boolean isShowing()

Returns

true if showing, false otherwise.

Description

Checks to see if the Component is currently showing.

isValid

public boolean isValid()

Returns

true if valid, false otherwise.

Description

Checks to see if the Component is currently valid.

isVisible

public boolean isVisible()

Returns

true if visible, false otherwise.

Description

Checks to see if the Component is currently visible.

keyDown

public boolean keyDown (Event e, int key) (Deprecated)

Parameters

e

Event instance identifying what triggered the call to this method.

key

Integer representation of key pressed.

Returns

true if event handled, false to propagate it to parent container.

Description

Method called whenever the user presses a key. Replaced by processKeyEvent(KeyEvent).

keyUp

public boolean keyUp (Event e, int key) (Deprecated)

Parameters

e

Event instance identifying what triggered the call to this method.

key

Integer representation of key released.

Returns

true if event handled, false to propagate it to parent container.

Description

Method called whenever the user releases a key. Replaced by processKeyEvent(KeyEvent).

layout

public void layout() (Deprecated)

Description

Lays out component. Replaced by doLayout().

list

public void list()

Description

Prints the contents of the Component to System.out.

public void list (PrintStream out)

Parameters

out

Output stream to send results to.

Description

Prints the contents of the Component to a PrintStream.

public void list (PrintStream out, int indentation)

Parameters

out

Output stream to send results to.

indentation

Indentation to use when printing.

Description

Prints the contents of the Component indented to a PrintStream.

public void list (PrintWriter out)

Parameters

out

Output stream to send results to.

Description

Prints the contents of the Component to a PrintWriter.

public void list (PrintWriter out, int indentation)

Parameters

out

Output stream to send results to.

indentation

Indentation to use when printing.

Description

Prints the contents of the Component indented to a PrintWriter.

locate

public Component locate (int x, int y) (Deprecated)

Parameters

x

Horizontal position.

y

Vertical position.

Returns

Component if the point (x, y) falls within the component, null otherwise.

Description

Replaced by getComponentAt(int, int).

location

public Point location() (Deprecated)

Returns

Position of component.

Description

Gets the current position of this Component in its parent's coordinate space. Replaced by getLocation().

lostFocus

public boolean lostFocus (Event e, Object o) (Deprecated)

Parameters

e

Event instance identifying what triggered the call to this method.

o

Argument specific to the component subclass that generated the event.

Returns

true if event handled, false to propagate it to parent container.

Description

Method called when Component loses input focus. Replaced by processFocusEvent(FocusEvent).

minimizeSize

public Dimension minimumSize() (Deprecated)

Returns

The minimum dimensions of the component. Replaced by getMinimumSize().

mouseDown

public boolean mouseDown (Event e, int x, int y) (Deprecated)

Parameters

e

Event instance identifying what triggered the call to this method.

x

Horizontal position of the mouse within Component when Event initiated

y

Vertical position of the mouse within Component when Event initiated

Returns

true if event handled, false to propagate it to parent container.

Description

Method called when the user presses a mouse button over Component. Replaced by processMouseEvent(MouseEvent).

mouseDrag

public boolean mouseDrag (Event e, int x, int y) (Deprecated)

Parameters

e

Event instance identifying what triggered the call to this method.

x

Horizontal position of the mouse within Component when Event initiated

y

Vertical position of the mouse within Component when Event initiated

Returns

true if event handled, false to propagate it to parent container.

Description

Method called when the user is pressing a mouse button and moves the mouse. Replaced by processMouseMotionEvent(MouseEvent).

mouseEnter

public boolean mouseEnter (Event e, int x, int y) (Deprecated)

Parameters

e

Event instance identifying what triggered the call to this method.

x

Horizontal position of the mouse within Component when Event initiated

y

Vertical position of the mouse within Component when Event initiated

Returns

true if event handled, false to propagate it to parent container.

Description

Method called when the mouse enters Component. Replaced by processMouseEvent(MouseEvent).

mouseExit

public boolean mouseExit (Event e, int x, int y) (Deprecated)

Parameters

e

Event instance identifying what triggered the call to this method.

x

Horizontal position of the mouse within Component when Event initiated

y

Vertical position of the mouse within Component when Event initiated

Returns

true if event handled, false to propagate it to parent container.

Description

Method called when the mouse exits Component. Replaced by processMouseEvent(MouseEvent).

mouseMove

public boolean mouseMove (Event e, int x, int y) (Deprecated)

Parameters

e

Event instance identifying what triggered the call to this method.

x

Horizontal position of the mouse within Component when Event initiated

y

Vertical position of the mouse within Component when Event initiated

Returns

true if event handled, false to propagate it to parent container.

Description

Method called when the user is not pressing a mouse button and moves the mouse. Replaced by processMouseMotionEvent(MouseEvent).

mouseUp

public boolean mouseUp (Event e, int x, int y) (Deprecated)

Parameters

e

Event instance identifying what triggered the call to this method.

x

Horizontal position of the mouse within Component when Event initiated

y

Vertical position of the mouse within Component when Event initiated

Returns

true if event is handled, false to propagate it to the parent container.

Description

Method called when user releases mouse button over Component. Replaced by processMouseEvent(MouseEvent).

move

public void move (int x, int y) (Deprecated)

Parameters

x

New horizontal position for component.

y

New vertical position for component.

Description

Relocates component. Replaced by setLocation(int, int).

nextFocus

public void nextFocus() (Deprecated)

Description

Moves focus from current component to next one in parent container. Replaced by transferFocus().

paint

public void paint (Graphics g)

Parameters

g

Graphics context of component.

Description

Empty method to be overridden to draw something in the graphics context.

paintAll

public void paintAll (Graphics g)

Parameters

g

Graphics context of component.

Description

Method to validate component and paint its peer if it is visible.

postEvent

public boolean postEvent (Event e) (Deprecated)

Parameters

e

Event instance to post to component

Returns

If Event is handled, true is returned. Otherwise, false is returned.

Description

Tells Component to deal with Event.

preferredSize

public Dimension preferredSize() (Deprecated)

Returns

The preferred dimensions of the component. Replaced by getPreferredSize().

prepareImage

public boolean prepareImage (Image image, ImageObserver observer)

Parameters

image

Image to start loading.

observer

Component on which image will be rendered.

Returns

true if Image is fully loaded, false otherwise.

Description

Forces Image to start loading.

public boolean prepareImage (Image image, int width, int height, ImageObserver observer)

Parameters

image

Image to start loading.

width

Horizontal size of the Image after scaling.

height

Vertical size of the Image after scaling.

observer

Component on which image will be rendered.

Returns

true if Image is fully loaded, false otherwise.

Description

Forces Image to start loading.

print

public void print (Graphics g)

Parameters

g

Graphics context.

Description

Empty method to be overridden to print something into the graphics context.

printAll

public void printAll (Graphics g)

Parameters

g

Graphics context.

Description

Method to print this component and its children.

remove

public void remove (MenuComponent popup) (New)

Parameters

popup

The menu to remove.

Description

After adding a PopupMenu, you can use this method to remove it.

removeComponentListener

public void removeComponentListener (ComponentListener l) (New)

Description

Removes the specified ComponentListener from this Component.

removeFocusListener

public void removeFocusListener (FocusListener l) (New)

Description

Removes the specified FocusListener from this Component.

removeKeyListener

public void removeKeyListener (KeyListener l) (New)

Description

Removes the specified KeyListener from this Component.

removeMouseListener

public void removeMouseListener (MouseListener l) (New)

Description

Removes the specified MouseListener from this Component.

removeMouseMotionListener

public void removeMouseMotionListener (MouseMotionListener l) (New)

Description

Removes the specified MouseMotionListener from this Component.

removeNotify

public void removeNotify()

Description

Removes peer of Component's subclass.

repaint

public void repaint()

Description

Requests scheduler to redraw the component as soon as possible.

public void repaint (long tm)

Parameters

tm

Millisecond delay allowed before repaint.

Description

Requests scheduler to redraw the component within a time period.

public void repaint (int x, int y, int width, int height)

Parameters

x

Horizontal origin of bounding box to redraw.

y

Vertical origin of bounding box to redraw.

width

Width of bounding box to redraw.

height

Height of bounding box to redraw.

Description

Requests scheduler to redraw a portion of component as soon as possible.

public void repaint (long tm, int x, int y, int width, int height)

Parameters

tm

Millisecond delay allowed before repaint.

x

Horizontal origin of bounding box to redraw.

y

Vertical origin of bounding box to redraw.

width

Width of bounding box to redraw.

height

Height of bounding box to redraw.

Description

Requests scheduler to redraw a portion of component within a time period.

requestFocus

public void requestFocus()

Description

Requests the input focus for this Component.

reshape

public void reshape (int x, int y, int width, int height) (Deprecated)

Parameters

x

New horizontal position for component.

y

New vertical position for component.

width

New width for component.

height

New height for component.

Description

Relocates and resizes component. Replaced by setBounds(int, int, int, int).

resize

public void resize (Dimension d) (Deprecated)

Parameters

d

New dimensions for the component.

Description

Resizes component. Replaced by setSize(Dimension).

public void resize (int width, int height) (Deprecated)

Parameters

width

New width for component.

height

New height for component.

Description

Resizes component. Replaced by setSize(int, int).

setBackground

public void setBackground (Color c)

Parameters

c

New background color.

Description

Changes the component's background color.

setBounds

public void setBounds (int x, int y, int width, int height) (New)

Parameters

x

New horizontal position for component.

y

New vertical position for component.

width

New width for component.

height

New height for component.

Description

Relocates and resizes the component.

public void setBounds (Rectangle r) (New)

Parameters

r

New coordinates for component.

Description

Relocates and resizes component.

setCursor

public synchronized void setCursor (Cursor cursor) (New)

Parameters

cursor

The new cursor for the component.

Description

Changes the component's cursor.

setEnabled

public void setEnabled (boolean b) (New)

Parameters

b

true to enable the component, false to disable it.

Description

Enables or disables the component. Replaces enable(), enable(boolean), and disable().

setFont

public synchronized void setFont (Font f)

Parameters

f

Font to change component to.

Description

Changes the font of the component.

setForeground

public void setForeground (Color c)

Parameters

c

New foreground color.

Description

Changes the foreground color of component's area.

setLocale

public void setLocale (Locale l) (New)

Parameters

l

The locale object for the component.

Description

Sets the Component's locale.

setLocation

public void setLocation (int x, int y) (New)

Parameters

x

New horizontal position for component.

y

New vertical position for component.

Description

Relocates the component.

public void setLocation (Point p) (New)

Parameters

p

New position for component.

Description

Relocates the component.

setName

public void setName (String name) (New)

Parameters

name

New name for component.

Description

Sets the component's name.

setSize

public void setSize (int width, int height) (New)

Parameters

width

New width for component.

height

New height for component.

Description

Resizes the component.

public void setSize (Dimension d) (New)

Parameters

d

New dimensions for the component.

Description

Resizes the component.

setVisible

public void setVisible (boolean b) (New)

Parameters

b

true to show component, false to hide it.

Description

Shows or hides the component based on the b parameter.

show

public void show() (Deprecated)

Description

Replaced by setVisible(true).

public void show (boolean condition) (Deprecated)

Parameters

condition

true to show the component, false to hide it.

Description

Replaced by setVisible(boolean).

size

public Dimension size() (Deprecated)

Returns

Dimensions of the component.

Description

Gets width and height of the component. Replaced by getSize().

toString

public String toString()

Returns

A string representation of the Component object.

Overrides

Object.toString()

transferFocus

public void transferFocus() (New)

Description

Transfers focus to the next component in the container hierarchy.

update

public void update (Graphics g)

Parameters

g

Graphics context of component.

Description

Called to update the component's display area.

validate

public void validate()

Description

Sets the component's valid state to true.

Protected Instance Methods

disableEvents

protected final void disableEvents (long eventsToDisable) (New)

Parameters

eventsToDisable

A value representing certain kinds of events. This can be constructed by ORing the event mask constants defined in java.awt.AWTEvent.

Description

By default, a component receives events corresponding to the event listeners that have registered. If a component should not receive events of a certain type, even if there is a listener registered for that type of event, this method can be used to disable that event type.

enableEvents

protected final void enableEvents (long eventsToEnable) (New)

Parameters

eventsToEnable

A value representing certain kinds of events. This can be constructed by ORing the event mask constants defined in java.awt.AWTEvent.

Description

By default, a component receives events corresponding to the event listeners that have registered. If a component should receive other types of events as well, this method can be used to request them.

paramString

protected String paramString()

Returns

A String with the current settings of the Component.

Description

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

processComponentEvent

protected void processComponentEvent(ComponentEvent e) (New)

Parameters

e

The event to process.

Description

Component events are passed to this method for processing. Normally, this method is called by processEvent().

processEvent

protected void processEvent(AWTEvent e) (New)

Parameters

e

The event to process.

Description

Low level AWTEvents are passed to this method for processing.

processFocusEvent

protected void processFocusEvent(FocusEvent e) (New)

Parameters

e

The event to process.

Description

Focus events are passed to this method for processing. Normally, this method is called by processEvent().

processKeyEvent

protected void processKeyEvent(KeyEvent e) (New)

Parameters

e

The event to process.

Description

Key events are passed to this method for processing. Normally, this method is called by processEvent().

processMouseEvent

protected void processMouseEvent(MouseEvent e) (New)

Parameters

e

The event to process.

Description

Mouse events are passed to this method for processing. Normally, this method is called by processEvent().

processMouseMotionEvent

protected void processMouseMotionEvent(MouseEvent e) (New)

Parameters

e

The event to process.

Description

Mouse motion events are passed to this method for processing. Normally, this method is called by processEvent().

See Also

Button, Canvas, Checkbox, Choice, Color, ColorModel, ComponentPeer, Container, Dimension, Event, Font, FontMetrics, Graphics, ImageObserver, ImageProducer, Label, List, MenuContainer, Object, Point, PrintStream, Rectangle, Scrollbar, Serializable, String, TextComponent, Toolkit

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