javax.swing.text.DefaultCaret — clojure-interop/javax.swing 1.0.5

A default implementation of Caret. The caret is rendered as a vertical line in the color specified by the CaretColor property of the associated JTextComponent. It can blink at the rate specified by the BlinkRate property.

This implementation expects two sources of asynchronous notification. The timer thread fires asynchronously, and causes the caret to simply repaint the most recent bounding box. The caret also tracks change as the document is modified. Typically this will happen on the event dispatch thread as a result of some mouse or keyboard event. The caret behavior on both synchronous and asynchronous documents updates is controlled by UpdatePolicy property. The repaint of the new caret location will occur on the event thread in any case, as calls to modelToView are only safe on the event thread.

The caret acts as a mouse and focus listener on the text component it has been installed in, and defines the caret semantics based upon those events. The listener methods can be reimplemented to change the semantics. By default, the first mouse button will be used to set focus and caret position. Dragging the mouse pointer with the first mouse button will sweep out a selection that is contiguous in the model. If the associated text component is editable, the caret will become visible when focus is gained, and invisible when focus is lost.

The Highlighter bound to the associated text component is used to render the selection by default. Selection appearance can be customized by supplying a painter to use for the highlights. By default a painter is used that will render a solid color as specified in the associated text component in the SelectionColor property. This can easily be changed by reimplementing the getSelectionPainter method.

A customized caret appearance can be achieved by reimplementing the paint method. If the paint method is changed, the damage method should also be reimplemented to cause a repaint for the area needed to render the caret. The caret extends the Rectangle class which is used to hold the bounding box for where the caret was last rendered. This enables the caret to repaint in a thread-safe manner when the caret moves without making a call to modelToView which is unstable between model updates and view repair (i.e. the order of delivery to DocumentListeners is not guaranteed).

The magic caret position is set to null when the caret position changes. A timer is used to determine the new location (after the caret change). When the timer fires, if the magic caret position is still null it is reset to the current caret position. Any actions that change the caret position and want the magic caret position to remain the same, must remember the magic caret position, change the cursor, and then set the magic caret position to its original value. This has the benefit that only actions that want the magic caret position to persist (such as open/down) need to know about it.

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans™ has been added to the java.beans package. Please see XMLEncoder.

*-always-update clj

Static Constant.

Indicates that the caret position is to be always updated accordingly to the document changes regardless whether the document updates are performed on the Event Dispatching Thread or not.

type: int

*-never-update clj

Static Constant.

Indicates that the caret should remain at the same absolute position in the document regardless of any document updates, except when the document length becomes less than the current caret position due to removal. In that case the caret position is adjusted to the end of the document.

type: int

*-update-when-on-edt clj

Static Constant.

Indicates that the caret position is to be updated only when document changes are performed on the Event Dispatching Thread.

type: int

->default-caret clj

(->default-caret)

Constructor.

Constructs a default caret.

active? clj

(active? this)

Determines if the caret is currently active.

This method returns whether or not the Caret is currently in a blinking state. It does not provide information as to whether it is currently blinked on or off. To determine if the caret is currently painted use the isVisible method.

returns: true if active else false - boolean

add-change-listener clj

(add-change-listener this l)

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

l - the listener - javax.swing.event.ChangeListener

deinstall clj

(deinstall this c)

Called when the UI is being removed from the interface of a JTextComponent. This is used to unregister any listeners that were attached.

c - the component - javax.swing.text.JTextComponent

equals clj

(equals this obj)

Compares this object to the specified object. The superclass behavior of comparing rectangles is not desired, so this is changed to the Object behavior.

obj - the object to compare this font with - java.lang.Object

returns: true if the objects are equal; false otherwise - boolean

focus-gained clj

(focus-gained this e)

Called when the component containing the caret gains focus. This is implemented to set the caret to visible if the component is editable.

e - the focus event - java.awt.event.FocusEvent

focus-lost clj

(focus-lost this e)

Called when the component containing the caret loses focus. This is implemented to set the caret to visibility to false.

e - the focus event - java.awt.event.FocusEvent

get-blink-rate clj

(get-blink-rate this)

Gets the caret blink rate.

returns: the delay in milliseconds. If this is zero the caret will not blink. - int

get-change-listeners clj

(get-change-listeners this)

Returns an array of all the change listeners registered on this caret.

returns: all of this caret's ChangeListeners or an empty array if no change listeners are currently registered - javax.swing.event.ChangeListener[]

get-dot clj

(get-dot this)

Fetches the current position of the caret.

returns: the position >= 0 - int

get-dot-bias clj

(get-dot-bias this)

Returns the bias of the caret position.

returns: the bias of the caret position - javax.swing.text.Position$Bias

get-listeners clj

(get-listeners this listener-type)

Returns an array of all the objects currently registered as FooListeners upon this caret. FooListeners 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 DefaultCaret c for its change listeners with the following code:

ChangeListener[] cls = (ChangeListener[])(c.getListeners(ChangeListener.class));

If no such listeners exist, this method returns an empty array.

listener-type - the type of listeners requested; this parameter should specify an interface that descends from java.util.EventListener - java.lang.Class

returns: an array of all objects registered as FooListeners on this component, or an empty array if no such listeners have been added - <T extends java.util.EventListener> T[]

throws: java.lang.ClassCastException - if listenerType doesn't specify a class or interface that implements java.util.EventListener

get-magic-caret-position clj

(get-magic-caret-position this)

Gets the saved caret position.

returns: the position see #setMagicCaretPosition - java.awt.Point

get-mark clj

(get-mark this)

Fetches the current position of the mark. If there is a selection, the dot and mark will not be the same.

returns: the position >= 0 - int

get-mark-bias clj

(get-mark-bias this)

Returns the bias of the mark.

returns: the bias of the mark - javax.swing.text.Position$Bias

get-update-policy clj

(get-update-policy this)

Gets the caret movement policy on document updates.

returns: one of the following values : UPDATE_WHEN_ON_EDT, NEVER_UPDATE, ALWAYS_UPDATE - int

install clj

(install this 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. Sets the dot and mark to 0, and establishes document, property change, focus, mouse, and mouse motion listeners.

c - the component - javax.swing.text.JTextComponent

mouse-clicked clj

(mouse-clicked this e)

Called when the mouse is clicked. If the click was generated from button1, a double click selects a word, and a triple click the current line.

e - the mouse event - java.awt.event.MouseEvent

mouse-dragged clj

(mouse-dragged this e)

Moves the caret position according to the mouse pointer's current location. This effectively extends the selection. By default, this is only done for mouse button 1.

e - the mouse event - java.awt.event.MouseEvent

mouse-entered clj

(mouse-entered this e)

Called when the mouse enters a region.

e - the mouse event - java.awt.event.MouseEvent

mouse-exited clj

(mouse-exited this e)

Called when the mouse exits a region.

e - the mouse event - java.awt.event.MouseEvent

mouse-moved clj

(mouse-moved this e)

Called when the mouse is moved.

e - the mouse event - java.awt.event.MouseEvent

mouse-pressed clj

(mouse-pressed this e)

If button 1 is pressed, this is implemented to request focus on the associated text component, and to set the caret position. If the shift key is held down, the caret will be moved, potentially resulting in a selection, otherwise the caret position will be set to the new location. If the component is not enabled, there will be no request for focus.

e - the mouse event - java.awt.event.MouseEvent

mouse-released clj

(mouse-released this e)

Called when the mouse is released.

e - the mouse event - java.awt.event.MouseEvent

move-dot clj

(move-dot this dot)

(move-dot this dot dot-bias)

Moves the caret position to the specified position, with the specified bias.

dot - the position >= 0 - int dot-bias - the bias for this position, not null - javax.swing.text.Position$Bias

throws: java.lang.IllegalArgumentException - if the bias is null

paint clj

(paint this g)

Renders the caret as a vertical line. If this is reimplemented the damage method should also be reimplemented as it assumes the shape of the caret is a vertical line. Sets the caret color to the value returned by getCaretColor().

If there are multiple text directions present in the associated document, a flag indicating the caret bias will be rendered. This will occur only if the associated document is a subclass of AbstractDocument and there are multiple bidi levels present in the bidi element structure (i.e. the text has multiple directions associated with it).

g - the graphics context - java.awt.Graphics

remove-change-listener clj

(remove-change-listener this l)

Removes a listener that was tracking caret position changes.

l - the listener - javax.swing.event.ChangeListener

selection-visible? clj

(selection-visible? this)

Checks whether the current selection is visible.

returns: true if the selection is visible - boolean

set-blink-rate clj

(set-blink-rate this rate)

Sets the caret blink rate.

rate - the rate in milliseconds, 0 to stop blinking - int

set-dot clj

(set-dot this dot)

(set-dot this dot dot-bias)

Sets the caret position and mark to the specified position, with the specified bias. This implicitly sets the selection range to zero.

dot - the position >= 0 - int dot-bias - the bias for this position, not null - javax.swing.text.Position$Bias

throws: java.lang.IllegalArgumentException - if the bias is null

set-magic-caret-position clj

(set-magic-caret-position this p)

Saves the current caret position. This is used when caret up/down actions occur, moving between lines that have uneven end positions.

p - the position - java.awt.Point

set-selection-visible clj

(set-selection-visible this vis)

Changes the selection visibility.

vis - the new visibility - boolean

set-update-policy clj

(set-update-policy this policy)

Sets the caret movement policy on the document updates. Normally the caret updates its absolute position within the document on insertions occurred before or at the caret position and on removals before the caret position. 'Absolute position' means here the position relative to the start of the document. For example if a character is typed within editable text component it is inserted at the caret position and the caret moves to the next absolute position within the document due to insertion and if BACKSPACE is typed then caret decreases its absolute position due to removal of a character before it. Sometimes it may be useful to turn off the caret position updates so that the caret stays at the same absolute position within the document position regardless of any document updates.

The following update policies are allowed:

NEVER_UPDATE: the caret stays at the same absolute position in the document regardless of any document updates, except when document length becomes less than the current caret position due to removal. In that case caret position is adjusted to the end of the document. The caret doesn't try to keep itself visible by scrolling the associated view when using this policy. ALWAYS_UPDATE: the caret always tracks document changes. For regular changes it increases its position if an insertion occurs before or at its current position, and decreases position if a removal occurs before its current position. For undo/redo updates it is always moved to the position where update occurred. The caret also tries to keep itself visible by calling adjustVisibility method. UPDATE_WHEN_ON_EDT: acts like ALWAYS_UPDATE if the document updates are performed on the Event Dispatching Thread and like NEVER_UPDATE if updates are performed on other thread.

The default property value is UPDATE_WHEN_ON_EDT.

policy - one of the following values : UPDATE_WHEN_ON_EDT, NEVER_UPDATE, ALWAYS_UPDATE - int

throws: java.lang.IllegalArgumentException - if invalid value is passed

set-visible clj

(set-visible this e)

Sets the caret visibility, and repaints the caret. It is important to understand the relationship between this method, isVisible and isActive. Calling this method with a value of true activates the caret blinking. Setting it to false turns it completely off. To determine whether the blinking is active, you should call isActive. In effect, isActive is an appropriate corresponding "getter" method for this one. isVisible can be used to fetch the current visibility status of the caret, meaning whether or not it is currently painted. This status will change as the caret blinks on and off.

Here's a list showing the potential return values of both isActive and isVisible after calling this method:

setVisible(true):

 isActive(): true
 isVisible(): true or false depending on whether
     or not the caret is blinked on or off

setVisible(false):

 isActive(): false
 isVisible(): false

e - the visibility specifier - boolean

to-string clj

(to-string this)

Description copied from class: Rectangle

returns: a String representing this Rectangle object's coordinate and size values. - java.lang.String

visible? clj

(visible? this)

Indicates whether or not the caret is currently visible. As the caret flashes on and off the return value of this will change between true, when the caret is painted, and false, when the caret is not painted. isActive indicates whether or not the caret is in a blinking state, such that it can be visible, and isVisible indicates whether or not the caret is actually visible.

Subclasses that wish to render a different flashing caret should override paint and only paint the caret if this method returns true.

returns: true if visible else false - boolean