public class Label extends Component implements Accessible
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 labels:
Modifier and Type | Class and Description |
---|---|
protected class |
Label.AccessibleAWTLabel This class implements accessibility support for the |
Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy
public static final int LEFT
Indicates that the label should be left justified.
public static final int CENTER
Indicates that the label should be centered.
public static final int RIGHT
Indicates that the label should be right justified.
public Label() throws HeadlessException
Constructs an empty label. The text of the label is the empty string ""
.
HeadlessException
- if GraphicsEnvironment.isHeadless() returns true.GraphicsEnvironment.isHeadless()
public Label(String text) throws HeadlessException
Constructs a new label with the specified string of text, left justified.
text
- the string that the label presents. A null
value will be accepted without causing a NullPointerException to be thrown.HeadlessException
- if GraphicsEnvironment.isHeadless() returns true.GraphicsEnvironment.isHeadless()
public Label(String text, int alignment) throws HeadlessException
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
.
text
- the string that the label presents. A null
value will be accepted without causing a NullPointerException to be thrown.alignment
- the alignment value.HeadlessException
- if GraphicsEnvironment.isHeadless() returns true.GraphicsEnvironment.isHeadless()
public void addNotify()
Creates the peer for this label. The peer allows us to modify the appearance of the label without changing its functionality.
addNotify
in class Component
Component.isDisplayable()
, Component.removeNotify()
, Component.invalidate()
public int getAlignment()
Gets the current alignment of this label. Possible values are Label.LEFT
, Label.RIGHT
, and Label.CENTER
.
setAlignment(int)
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
.
alignment
- the alignment to be set.IllegalArgumentException
- if an improper value for alignment
is given.getAlignment()
public String getText()
Gets the text of this label.
null
if the text has been set to null
.setText(java.lang.String)
public void setText(String text)
Sets the text for this label to the specified text.
text
- the text that this label displays. If text
is null
, it is treated for display purposes like an empty string ""
.getText()
protected String paramString()
Returns a string representing the state of this Label
. This method is intended to be used only for debugging purposes, and the content and format of the returned string may vary between implementations. The returned string may be empty but may not be null
.
paramString
in class Component
public AccessibleContext getAccessibleContext()
Gets the AccessibleContext associated with this Label. For labels, the AccessibleContext takes the form of an AccessibleAWTLabel. A new AccessibleAWTLabel instance is created if necessary.
getAccessibleContext
in interface Accessible
getAccessibleContext
in class Component
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