java.awt
Class Label
java.lang.Object
|
+--java.awt.Component
|
+--java.awt.Label
- public class Label
- extends Component
A Label
object is a component for placing text in a
container. A label displays a single line of read-only text.
The text can be changed by the application, but a user cannot edit it
directly.
For example, the code . . .
setLayout(new FlowLayout(FlowLayout.CENTER, 10, 10));
add(new Label("Hi There!"));
add(new Label("Another Label"));
produces the following label:
- Since:
- JDK1.0
- See Also:
- Serialized Form
Field Summary |
(package private) int |
alignment
The label's alignment. |
private static String |
base
|
static int |
CENTER
Indicates that the label should be centered. |
static int |
LEFT
Indicates that the label should be left justified. |
private static int |
nameCounter
|
static int |
RIGHT
Indicates that the label should be right justified. |
private static long |
serialVersionUID
|
(package private) String |
text
The text of this label. |
Fields inherited from class java.awt.Component |
actionListenerK,
adjustmentListenerK,
appContext,
assert,
background,
BOTTOM_ALIGNMENT,
CENTER_ALIGNMENT,
changeSupport,
componentListener,
componentListenerK,
componentOrientation,
componentSerializedDataVersion,
containerListenerK,
cursor,
dropTarget,
enabled,
eventMask,
focusListener,
focusListenerK,
font,
foreground,
hasFocus,
height,
incRate,
inputMethodListener,
inputMethodListenerK,
isInc,
isPacked,
itemListenerK,
keyListener,
keyListenerK,
LEFT_ALIGNMENT,
locale,
LOCK,
minSize,
mouseListener,
mouseListenerK,
mouseMotionListener,
mouseMotionListenerK,
name,
nameExplicitlySet,
newEventsOnly,
ownedWindowK,
parent,
peer,
peerFont,
popups,
prefSize,
RIGHT_ALIGNMENT,
serialVersionUID,
textListenerK,
TOP_ALIGNMENT,
valid,
visible,
width,
windowListenerK,
x,
y |
Constructor Summary |
Label()
Constructs an empty label. |
Label(String text)
Constructs a new label with the specified string of text,
left justified. |
Label(String text,
int alignment)
Constructs a new label that presents the specified string of
text with the specified alignment. |
Method Summary |
(package private) static void |
()
|
void |
addNotify()
Creates the peer for this label. |
(package private) String |
constructComponentName()
Construct a name for this component. |
int |
getAlignment()
Gets the current alignment of this label. |
String |
getText()
Gets the text of this label. |
private static void |
initIDs()
Initialize JNI field and method IDs |
protected String |
paramString()
Returns the parameter string representing the state of this
label. |
void |
setAlignment(int alignment)
Sets the alignment for this label to the specified alignment. |
void |
setText(String text)
Sets the text for this label to the specified text. |
Methods inherited from class java.awt.Component |
action,
add,
addComponentListener,
addFocusListener,
addInputMethodListener,
addKeyListener,
addMouseListener,
addMouseMotionListener,
addPropertyChangeListener,
addPropertyChangeListener,
areInputMethodsEnabled,
bounds,
checkImage,
checkImage,
coalesceEvents,
contains,
contains,
createImage,
createImage,
deliverEvent,
disable,
disableEvents,
dispatchEvent,
dispatchEventImpl,
doLayout,
enable,
enable,
enableEvents,
enableInputMethods,
eventEnabled,
firePropertyChange,
getAlignmentX,
getAlignmentY,
getBackground,
getBounds,
getBounds,
getColorModel,
getComponentAt,
getComponentAt,
getComponentOrientation,
getCursor,
getDropTarget,
getFont_NoClientCode,
getFont,
getFontMetrics,
getForeground,
getGraphics,
getHeight,
getInputContext,
getInputMethodRequests,
getLocale,
getLocation,
getLocation,
getLocationOnScreen,
getMaximumSize,
getMinimumSize,
getName,
getNativeContainer,
getParent_NoClientCode,
getParent,
getPeer,
getPreferredSize,
getSize,
getSize,
getToolkit,
getToolkitImpl,
getTreeLock,
getWidth,
getWindowForObject,
getX,
getY,
gotFocus,
handleEvent,
hasFocus,
hide,
imageUpdate,
inside,
invalidate,
isDisplayable,
isDoubleBuffered,
isEnabled,
isEnabledImpl,
isFocusTraversable,
isLightweight,
isOpaque,
isShowing,
isValid,
isVisible,
keyDown,
keyUp,
layout,
lightweightPrint,
list,
list,
list,
list,
list,
locate,
location,
lostFocus,
minimumSize,
mouseDown,
mouseDrag,
mouseEnter,
mouseExit,
mouseMove,
mouseUp,
move,
nextFocus,
paint,
paintAll,
postEvent,
postsOldMouseEvents,
preferredSize,
prepareImage,
prepareImage,
print,
printAll,
processComponentEvent,
processEvent,
processFocusEvent,
processInputMethodEvent,
processKeyEvent,
processMouseEvent,
processMouseMotionEvent,
readObject,
remove,
removeComponentListener,
removeFocusListener,
removeInputMethodListener,
removeKeyListener,
removeMouseListener,
removeMouseMotionListener,
removeNotify,
removePropertyChangeListener,
removePropertyChangeListener,
repaint,
repaint,
repaint,
repaint,
requestFocus,
reshape,
resize,
resize,
setBackground,
setBounds,
setBounds,
setComponentOrientation,
setCursor,
setDropTarget,
setEnabled,
setFont,
setForeground,
setLocale,
setLocation,
setLocation,
setName,
setSize,
setSize,
setVisible,
show,
show,
size,
toString,
transferFocus,
update,
validate,
writeObject |
Methods inherited from class java.lang.Object |
clone,
equals,
finalize,
getClass,
hashCode,
notify,
notifyAll,
registerNatives,
wait,
wait,
wait |
LEFT
public static final int LEFT
- Indicates that the label should be left justified.
CENTER
public static final int CENTER
- Indicates that the label should be centered.
RIGHT
public static final int RIGHT
- Indicates that the label should be right justified.
- Since:
- JDK1.0t.
text
String text
- The text of this label.
This text can be modified by the program
but never by the user.
- See Also:
getText()
,
setText()
alignment
int alignment
- The label's alignment. The default alignment is set
to be left justified.
- See Also:
getAlignment()
,
setAlignment()
base
private static final String base
nameCounter
private static int nameCounter
serialVersionUID
private static final long serialVersionUID
Label
public Label()
- Constructs an empty label.
The text of the label is the empty string
""
.
Label
public Label(String text)
- Constructs a new label with the specified string of text,
left justified.
- Parameters:
text
- the string that the label presents.
A null
value
will be accepted without causing a NullPointerException
to be thrown.
Label
public Label(String text,
int alignment)
- Constructs a new label that presents the specified string of
text with the specified alignment.
Possible values for
alignment
are Label.LEFT
,
Label.RIGHT
, and Label.CENTER
.
- Parameters:
text
- the string that the label presents.
A null
value
will be accepted without causing a NullPointerException
to be thrown.alignment
- the alignment value.
static void ()
constructComponentName
String constructComponentName()
- Construct a name for this component. Called by getName() when the
name is
null
.
- Overrides:
- constructComponentName in class Component
addNotify
public void addNotify()
- Creates the peer for this label. The peer allows us to
modify the appearance of the label without changing its
functionality.
- Overrides:
- addNotify in class Component
getAlignment
public int getAlignment()
- Gets the current alignment of this label. Possible values are
Label.LEFT
, Label.RIGHT
, and
Label.CENTER
.
- See Also:
setAlignment(int)
setAlignment
public void setAlignment(int alignment)
- Sets the alignment for this label to the specified alignment.
Possible values are
Label.LEFT
,
Label.RIGHT
, and Label.CENTER
.
- Parameters:
alignment
- the alignment to be set.- Throws:
- IllegalArgumentException - if an improper value for
alignment
is given. - See Also:
getAlignment()
getText
public String getText()
- Gets the text of this label.
- Returns:
- the text of this label, or
null
if
the text has been set to null
. - See Also:
setText(java.lang.String)
setText
public void setText(String text)
- Sets the text for this label to the specified text.
- Parameters:
text
- the text that this label displays. If
text
is null
, it is
treated for display purposes like an empty
string ""
.- See Also:
getText()
paramString
protected String paramString()
- Returns the parameter string representing the state of this
label. This string is useful for debugging.
- Returns:
- the parameter string of this label.
- Overrides:
- paramString in class Component
initIDs
private static void initIDs()
- Initialize JNI field and method IDs