public class Label extends Component implements Accessible
Label
对象是放置在一个容器组件的文本。标签显示只读文本的单行线。文本可以通过应用程序更改,但用户不能直接编辑它。
例如,代码 。 。 。
setLayout(new FlowLayout(FlowLayout.CENTER, 10, 10)); add(new Label("Hi There!")); add(new Label("Another Label"));
生产下列标签:
Modifier and Type | Class and Description |
---|---|
protected class |
Label.AccessibleAWTLabel
这个类实现了对
Label 类可访问性支持。
|
Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy
Modifier and Type | Field and Description |
---|---|
static int |
CENTER
指示标签应为中心。
|
static int |
LEFT
指示标签应该是左对齐的。
|
static int |
RIGHT
指示标签应该是正确的。
|
accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT
ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH
Constructor and Description |
---|
Label()
构造一个空标签。
|
Label(String text)
用指定的文本字符串构造一个新的标签,左对齐。
|
Label(String text, int alignment)
构造一个新的标签,该标签以指定的对齐方式呈现指定的文本字符串。
|
Modifier and Type | Method and Description |
---|---|
void |
addNotify()
创建此标签的对等体。
|
AccessibleContext |
getAccessibleContext()
获取与该标签相关联的accessiblecontext。
|
int |
getAlignment()
获取此标签的当前对齐方式。
|
String |
getText()
获取此标签的文本。
|
protected String |
paramString()
返回一个字符串,表示此
Label 状态。
|
void |
setAlignment(int alignment)
将此标签的对齐方式设置为指定的对齐方式。
|
void |
setText(String text)
将此标签的文本设置为指定的文本。
|
action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, createVolatileImage, createVolatileImage, deliverEvent, disable, disableEvents, dispatchEvent, doLayout, enable, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getAlignmentX, getAlignmentY, getBackground, getBaseline, getBaselineResizeBehavior, getBounds, getBounds, getColorModel, getComponentAt, getComponentAt, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeys, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphics, getGraphicsConfiguration, getHeight, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getListeners, getLocale, getLocation, getLocation, getLocationOnScreen, getMaximumSize, getMinimumSize, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPeer, getPreferredSize, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getSize, getToolkit, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, invalidate, isBackgroundSet, isCursorSet, isDisplayable, isDoubleBuffered, isEnabled, isFocusable, isFocusCycleRoot, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isOpaque, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, layout, list, list, list, list, list, locate, location, lostFocus, minimumSize, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paint, paintAll, postEvent, preferredSize, prepareImage, prepareImage, print, printAll, processComponentEvent, processEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removeNotify, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, reshape, resize, resize, revalidate, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeys, setFocusTraversalKeysEnabled, setFont, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setMaximumSize, setMinimumSize, setName, setPreferredSize, setSize, setSize, setVisible, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle, update, validate
public static final int LEFT
public static final int CENTER
public static final int RIGHT
public Label() throws HeadlessException
""
。
HeadlessException
-如果graphicsenvironment isheadless()返回true。
GraphicsEnvironment.isHeadless()
public Label(String text) throws HeadlessException
text
-标签的字符串。一个
null
值将不会造成NullPointerException被接受。
HeadlessException
-如果graphicsenvironment isheadless()返回true。
GraphicsEnvironment.isHeadless()
public Label(String text, int alignment) throws HeadlessException
alignment
可能值
Label.LEFT
,
Label.RIGHT
,和
Label.CENTER
。
text
-标签的字符串。一个
null
值将不会造成NullPointerException被接受。
alignment
的对齐值。
HeadlessException
-如果graphicsenvironment isheadless()返回true。
GraphicsEnvironment.isHeadless()
public void addNotify()
addNotify
方法重写,继承类
Component
Component.isDisplayable()
,
Component.removeNotify()
,
Component.invalidate()
public int getAlignment()
Label.LEFT
,
Label.RIGHT
,和
Label.CENTER
。
setAlignment(int)
public void setAlignment(int alignment)
Label.LEFT
,
Label.RIGHT
,和
Label.CENTER
。
alignment
-对齐设置。
IllegalArgumentException
如果
alignment
不当的价值了。
getAlignment()
public String getText()
null
如果文本已被设置为
null
。
setText(java.lang.String)
public void setText(String text)
text
-这个标签显示文本。如果
text
是
null
,它显示的像一个空字符串
""
治疗。
getText()
protected String paramString()
Label
状态。这种方法的目的是用于调试目的,其含量和返回的字符串格式不同的实现可能会有所不同。返回的字符串是空的但可能不
null
。
paramString
方法重写,继承类
Component
public AccessibleContext getAccessibleContext()
getAccessibleContext
接口
Accessible
getAccessibleContext
方法重写,继承类
Component
Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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