ImageObserver
, MenuContainer
, Serializable
, Accessible
public sealed class TextComponent extends Component implements Accessible permits TextArea, TextField
TextComponent
class is the superclass of any component that allows the editing of some text. A text component embodies a string of text. The TextComponent
class defines a set of methods that determine whether or not this text is editable. If the component is editable, it defines another set of methods that supports a text insertion caret.
In addition, the class defines methods that are used to maintain a current selection from the text. The text selection, a substring of the component's text, is the target of editing operations. It is also referred to as the selected text.
Modifier and Type | Class | Description |
---|---|---|
protected class |
TextComponent.AccessibleAWTTextComponent |
This class implements accessibility support for the TextComponent class. |
Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy
Modifier and Type | Field | Description |
---|---|---|
protected TextListener |
textListener |
A list of listeners that will receive events from this object. |
accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT
ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH
Modifier and Type | Method | Description |
---|---|---|
void |
addNotify() |
Makes this Component displayable by connecting it to a native screen resource. |
void |
addTextListener |
Adds the specified text event listener to receive text events from this text component. |
void |
enableInputMethods |
Enables or disables input method support for this text component. |
AccessibleContext |
getAccessibleContext() |
Gets the AccessibleContext associated with this TextComponent. |
Color |
getBackground() |
Gets the background color of this text component. |
int |
getCaretPosition() |
Returns the position of the text insertion caret. |
<T extends EventListener> |
getListeners |
Returns an array of all the objects currently registered as FooListener s upon this TextComponent . |
String |
getSelectedText() |
Returns the selected text from the text that is presented by this text component. |
int |
getSelectionEnd() |
Gets the end position of the selected text in this text component. |
int |
getSelectionStart() |
Gets the start position of the selected text in this text component. |
String |
getText() |
Returns the text that is presented by this text component. |
TextListener[] |
getTextListeners() |
Returns an array of all the text listeners registered on this text component. |
boolean |
isEditable() |
Indicates whether or not this text component is editable. |
protected String |
paramString() |
Returns a string representing the state of this TextComponent . |
protected void |
processEvent |
Processes events on this text component. |
protected void |
processTextEvent |
Processes text events occurring on this text component by dispatching them to any registered TextListener objects. |
void |
removeNotify() |
Removes the TextComponent 's peer. |
void |
removeTextListener |
Removes the specified text event listener so that it no longer receives text events from this text component If l is null , no exception is thrown and no action is performed. |
void |
select |
Selects the text between the specified start and end positions. |
void |
selectAll() |
Selects all the text in this text component. |
void |
setBackground |
Sets the background color of this text component. |
void |
setCaretPosition |
Sets the position of the text insertion caret. |
void |
setEditable |
Sets the flag that determines whether or not this text component is editable. |
void |
setSelectionEnd |
Sets the selection end for this text component to the specified position. |
void |
setSelectionStart |
Sets the selection start for this text component to the specified position. |
void |
setText |
Sets the text that is presented by this text component to be the specified text. |
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, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getAlignmentX, getAlignmentY, 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, getLocale, getLocation, getLocation, getLocationOnScreen, getMaximumSize, getMinimumSize, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, 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, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, requestFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, requestFocusInWindow, reshape, resize, resize, revalidate, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeys, setFocusTraversalKeysEnabled, setFont, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setMaximumSize, setMinimumSize, setMixingCutoutShape, setName, setPreferredSize, setSize, setSize, setVisible, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle, update, validate
protected transient TextListener textListener
public void enableInputMethods(boolean enable)
enableInputMethods
in class Component
enable
- true to enable, false to disablepublic void addNotify()
public void removeNotify()
TextComponent
's peer. The peer allows us to modify the appearance of the TextComponent
without changing its functionality.removeNotify
in class Component
public void setText(String t)
t
- the new text; if this parameter is null
then the text is set to the empty string ""public String getText()
TextComponent
public String getSelectedText()
public boolean isEditable()
true
if this text component is editable; false
otherwise.public void setEditable(boolean b)
If the flag is set to true
, this text component becomes user editable. If the flag is set to false
, the user cannot change the text of this text component. By default, non-editable text components have a background color of SystemColor.control. This default can be overridden by calling setBackground.
b
- a flag indicating whether this text component is user editable.public Color getBackground()
getBackground
in class Component
public void setBackground(Color c)
setBackground
in class Component
c
- The color to become this text component's color. If this parameter is null then this text component will inherit the background color of its parent.public int getSelectionStart()
public void setSelectionStart(int selectionStart)
selectionStart
that is out of bounds, the method enforces these constraints silently, and without failure.selectionStart
- the start position of the selected textpublic int getSelectionEnd()
public void setSelectionEnd(int selectionEnd)
selectionEnd
that is out of bounds, the method enforces these constraints silently, and without failure.selectionEnd
- the end position of the selected textpublic void select(int selectionStart, int selectionEnd)
This method sets the start and end positions of the selected text, enforcing the restriction that the start position must be greater than or equal to zero. The end position must be greater than or equal to the start position, and less than or equal to the length of the text component's text. The character positions are indexed starting with zero. The length of the selection is endPosition
- startPosition
, so the character at endPosition
is not selected. If the start and end positions of the selected text are equal, all text is deselected.
If the caller supplies values that are inconsistent or out of bounds, the method enforces these constraints silently, and without failure. Specifically, if the start position or end position is greater than the length of the text, it is reset to equal the text length. If the start position is less than zero, it is reset to zero, and if the end position is less than the start position, it is reset to the start position.
selectionStart
- the zero-based index of the first character (char
value) to be selectedselectionEnd
- the zero-based end position of the text to be selected; the character (char
value) at selectionEnd
is not selectedpublic void selectAll()
public void setCaretPosition(int position)
TextComponent
contains no text) and no error is returned. If the passed-in value is less than 0, an IllegalArgumentException
is thrown.position
- the position of the text insertion caretIllegalArgumentException
- if position
is less than zeropublic int getCaretPosition()
public void addTextListener(TextListener l)
l
is null
, no exception is thrown and no action is performed. Refer to AWT Threading Issues for details on AWT's threading model.
l
- the text event listenerpublic void removeTextListener(TextListener l)
l
is null
, no exception is thrown and no action is performed. Refer to AWT Threading Issues for details on AWT's threading model.
l
- the text listenerpublic TextListener[] getTextListeners()
TextListener
s or an empty array if no text listeners are currently registeredpublic <T extends EventListener> T[] getListeners(Class<T> listenerType)
FooListener
s upon this TextComponent
. FooListener
s are registered using the addFooListener
method. You can specify the listenerType
argument with a class literal, such as FooListener.class
. For example, you can query a TextComponent t
for its text listeners with the following code:
TextListener[] tls = (TextListener[])(t.getListeners(TextListener.class));If no such listeners exist, this method returns an empty array.
getListeners
in class Component
T
- the type of the listenerslistenerType
- the type of listeners requested; this parameter should specify an interface that descends from java.util.EventListener
FooListener
s on this text component, or an empty array if no such listeners have been addedClassCastException
- if listenerType
doesn't specify a class or interface that implements java.util.EventListener
protected void processEvent(AWTEvent e)
TextEvent
, it invokes the processTextEvent
method else it invokes its superclass's processEvent
. Note that if the event parameter is null
the behavior is unspecified and may result in an exception.
processEvent
in class Component
e
- the eventprotected void processTextEvent(TextEvent e)
TextListener
objects. NOTE: This method will not be called unless text events are enabled for this component. This happens when one of the following occurs:
TextListener
object is registered via addTextListener
enableEvents
Note that if the event parameter is null
the behavior is unspecified and may result in an exception.
e
- the text eventprotected String paramString()
TextComponent
. 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()
getAccessibleContext
in interface Accessible
getAccessibleContext
in class Component
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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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https://docs.oracle.com/en/java/javase/21/docs/api/java.desktop/java/awt/TextComponent.html