This documentation differs from the official API. Jadeite adds extra features to the API including: variable font sizes, constructions examples, placeholders for classes and methods, and auto-generated “See Also” links. Additionally it is missing some items found in standard Javadoc documentation, including: generics type information, “Deprecated” tags and comments, “See Also” links, along with other minor differences. Please send any questions or feedback to bam@cs.cmu.edu.


javax.swing.text
interface Caret

All Known Implementing Classes:
DefaultCaret, BasicTextUI.BasicCaret

Most common way to construct:

JTextComponent target = …;

Caret caret = target.getCaret();

Based on 8 examples


public interface Caret

A place within a document view that represents where things can be inserted into the document model. A caret has a position in the document referred to as a dot. The dot is where the caret is currently located in the model. There is a second position maintained by the caret that represents the other end of a selection called mark. If there is no selection the dot and mark will be equal. If a selection exists, the two values will be different.

The dot can be placed by either calling setDot or moveDot. Setting the dot has the effect of removing any selection that may have previously existed. The dot and mark will be equal. Moving the dot has the effect of creating a selection as the mark is left at whatever position it previously had.


Method Summary
 void

          Adds a listener to track whenever the caret position has been changed.
 void

          Called when the UI is being removed from the interface of a JTextComponent.
 int

          Gets the blink rate of the caret.
 int

          Fetches the current position of the caret.
 Point

          Gets the current caret visual location.
 int

          Fetches the current position of the mark.
 void

          Called when the UI is being installed into the interface of a JTextComponent.
 boolean

          Determines if the selection is currently visible.
 boolean

          Determines if the caret is currently visible.
 void
moveDot(int dot)

          Moves the caret position (dot) to some other position, leaving behind the mark.
 void

          Renders the caret.
 void

          Removes a listener that was tracking caret position changes.
 void
setBlinkRate(int rate)

          Sets the blink rate of the caret.
 void
setDot(int dot)

          Sets the caret position to some position.
 void

          Set the current caret visual location.
 void

          Sets the visibility of the selection
 void
setVisible(boolean v)

          Sets the visibility of the caret.
 

Method Detail

addChangeListener

public void addChangeListener(ChangeListener l)
Adds a listener to track whenever the caret position has been changed.

Parameters:
l - the change listener

deinstall

public void deinstall(JTextComponent c)
Called when the UI is being removed from the interface of a JTextComponent. This is used to unregister any listeners that were attached.

Parameters:
c - the JTextComponent

getBlinkRate

public int getBlinkRate()
Gets the blink rate of the caret. This determines if and how fast the caret blinks, commonly used as one way to attract attention to the caret.

Returns:
the delay in milliseconds >= 0. If this is zero the caret will not blink.

getDot

public int getDot()
Fetches the current position of the caret.

Returns:
the position >= 0

getMagicCaretPosition

public Point getMagicCaretPosition()
Gets the current caret visual location.

Returns:
the visual position.

getMark

public int getMark()
Fetches the current position of the mark. If there is a selection, the mark will not be the same as the dot.

Returns:
the position >= 0

install

public void install(JTextComponent c)
Called when the UI is being installed into the interface of a JTextComponent. This can be used to gain access to the model that is being navigated by the implementation of this interface.

Parameters:
c - the JTextComponent

isSelectionVisible

public boolean isSelectionVisible()
Determines if the selection is currently visible.

Returns:
true if the caret is visible else false

isVisible

public boolean isVisible()
Determines if the caret is currently visible.

Returns:
true if the caret is visible else false

moveDot

public void moveDot(int dot)
Moves the caret position (dot) to some other position, leaving behind the mark. This is useful for making selections.

Parameters:
dot - the new position to move the caret to >= 0

paint

public void paint(Graphics g)
Renders the caret. This method is called by UI classes.

Parameters:
g - the graphics context

removeChangeListener

public void removeChangeListener(ChangeListener l)
Removes a listener that was tracking caret position changes.

Parameters:
l - the change listener

setBlinkRate

public void setBlinkRate(int rate)
Sets the blink rate of the caret. This determines if and how fast the caret blinks, commonly used as one way to attract attention to the caret.

Parameters:
rate - the delay in milliseconds >= 0. If this is zero the caret will not blink.

setDot

public void setDot(int dot)
Sets the caret position to some position. This causes the mark to become the same as the dot, effectively setting the selection range to zero.

If the parameter is negative or beyond the length of the document, the caret is placed at the beginning or at the end, respectively.

Parameters:
dot - the new position to set the caret to

setMagicCaretPosition

public void setMagicCaretPosition(Point p)
Set the current caret visual location. This can be used when moving between lines that have uneven end positions (such as when caret up or down actions occur). If text flows left-to-right or right-to-left the x-coordinate will indicate the desired navigation location for vertical movement. If the text flow is top-to-bottom, the y-coordinate will indicate the desired navigation location for horizontal movement.

Parameters:
p - the Point to use for the saved position. This can be null to indicate there is no visual location.

setSelectionVisible

public void setSelectionVisible(boolean v)
Sets the visibility of the selection

Parameters:
v - true if the caret should be shown, and false if the caret should be hidden

setVisible

public void setVisible(boolean v)
Sets the visibility of the caret.

Parameters:
v - true if the caret should be shown, and false if the caret should be hidden


This documentation differs from the official API. Jadeite adds extra features to the API including: variable font sizes, constructions examples, placeholders for classes and methods, and auto-generated “See Also” links. Additionally it is missing some items found in standard Javadoc documentation, including: generics type information, “Deprecated” tags and comments, “See Also” links, along with other minor differences. Please send any questions or feedback to bam@cs.cmu.edu.
This page displays the Jadeite version of the documention, which is derived from the offical documentation that contains this copyright notice:
Copyright 2008 Sun Microsystems, Inc. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.
The official Sun™ documentation can be found here at http://java.sun.com/javase/6/docs/api/.