Module java.desktop

Package javax.swing.text

Class GlyphView

java.lang.Object

javax.swing.text.View

javax.swing.text.GlyphView

All Implemented Interfaces:

Cloneable, SwingConstants, TabableView

Direct Known Subclasses:

LabelView

public class GlyphView
extends View
implements TabableView, Cloneable

A GlyphView is a styled chunk of text that represents a view mapped over an element in the text model. This view is generally responsible for displaying text glyphs using character level attributes in some way. An implementation of the GlyphPainter class is used to do the actual rendering and model/view translations. This separates rendering from layout and management of the association with the model.

The view supports breaking for the purpose of formatting. The fragments produced by breaking share the view that has primary responsibility for the element (i.e. they are nested classes and carry only a small amount of state of their own) so they can share its resources.

Since this view represents text that may have tabs embedded in it, it implements the TabableView interface. Tabs will only be expanded if this view is embedded in a container that does tab expansion. ParagraphView is an example of a container that does tab expansion.

Since:

1.3

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	GlyphView.GlyphPainter	A class to perform rendering of the glyphs.

Field Summary

Fields declared in class javax.swing.text.View

BadBreakWeight, ExcellentBreakWeight, ForcedBreakWeight, GoodBreakWeight, X_AXIS, Y_AXIS

Fields declared in interface javax.swing.SwingConstants

BOTTOM, CENTER, EAST, HORIZONTAL, LEADING, LEFT, NEXT, NORTH, NORTH_EAST, NORTH_WEST, PREVIOUS, RIGHT, SOUTH, SOUTH_EAST, SOUTH_WEST, TOP, TRAILING, VERTICAL, WEST

Constructor Summary

Constructors

Constructor	Description
GlyphView(Element elem)	Constructs a new view wrapped on an element.

Method Summary

Modifier and Type	Method	Description
View	breakView(int axis, int p0, float pos, float len)	Breaks this view on the given axis at the given length.
void	changedUpdate(DocumentEvent e, Shape a, ViewFactory f)	Gives notification from the document that attributes were changed in a location that this view is responsible for.
protected void	checkPainter()	Check to see that a glyph painter exists.
protected Object	clone()	Creates a shallow copy.
View	createFragment(int p0, int p1)	Creates a view that represents a portion of the element.
float	getAlignment(int axis)	Determines the desired alignment for this view along an axis.
Color	getBackground()	Fetch the background color to use to render the glyphs.
int	getBreakWeight(int axis, float pos, float len)	Determines how attractive a break opportunity in this view is.
int	getEndOffset()	Fetches the portion of the model that this view is responsible for.
Font	getFont()	Fetch the font that the glyphs should be based upon.
Color	getForeground()	Fetch the foreground color to use to render the glyphs.
GlyphView.GlyphPainter	getGlyphPainter()	Fetch the currently installed glyph painter.
float	getMinimumSpan(int axis)	Determines the minimum span for this view along an axis.
int	getNextVisualPositionFrom(int pos, Position.Bias b, Shape a, int direction, Position.Bias[] biasRet)	Provides a way to determine the next visually represented model location that one might place a caret.
float	getPartialSpan(int p0, int p1)	Determines the span along the same axis as tab expansion for a portion of the view.
float	getPreferredSpan(int axis)	Determines the preferred span for this view along an axis.
int	getStartOffset()	Fetches the portion of the model that this view is responsible for.
float	getTabbedSpan(float x, TabExpander e)	Determines the desired span when using the given tab expansion implementation.
TabExpander	getTabExpander()	Fetch the TabExpander to use if tabs are present in this view.
Segment	getText(int p0, int p1)	Fetch a reference to the text that occupies the given range.
void	insertUpdate(DocumentEvent e, Shape a, ViewFactory f)	Gives notification that something was inserted into the document in a location that this view is responsible for.
boolean	isStrikeThrough()	Determine if the glyphs should have a strikethrough line.
boolean	isSubscript()	Determine if the glyphs should be rendered as superscript.
boolean	isSuperscript()	Determine if the glyphs should be rendered as subscript.
boolean	isUnderline()	Determine if the glyphs should be underlined.
Shape	modelToView(int pos, Shape a, Position.Bias b)	Provides a mapping from the document model coordinate space to the coordinate space of the view mapped to it.
void	paint(Graphics g, Shape a)	Renders a portion of a text style run.
void	removeUpdate(DocumentEvent e, Shape a, ViewFactory f)	Gives notification that something was removed from the document in a location that this view is responsible for.
void	setGlyphPainter(GlyphView.GlyphPainter p)	Sets the painter to use for rendering glyphs.
int	viewToModel(float x, float y, Shape a, Position.Bias[] biasReturn)	Provides a mapping from the view coordinate space to the logical coordinate space of the model.

Methods declared in class javax.swing.text.View

append, forwardUpdate, forwardUpdateToView, getAttributes, getChildAllocation, getContainer, getDocument, getElement, getGraphics, getMaximumSpan, getParent, getResizeWeight, getToolTipText, getView, getViewCount, getViewFactory, getViewIndex, getViewIndex, insert, isVisible, modelToView, modelToView, preferenceChanged, remove, removeAll, replace, setParent, setSize, updateChildren, updateLayout, viewToModel

Methods declared in class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

GlyphView

public GlyphView(Element elem)

Constructs a new view wrapped on an element.

Parameters:

elem - the element

Method Details

clone

protected final Object clone()

Creates a shallow copy. This is used by the createFragment and breakView methods.

Overrides:

clone in class Object

Returns:

the copy

See Also:

Cloneable

getGlyphPainter

public GlyphView.GlyphPainter getGlyphPainter()

Fetch the currently installed glyph painter. If a painter has not yet been installed, and a default was not yet needed, null is returned.

Returns:

the currently installed glyph painter

setGlyphPainter

public void setGlyphPainter(GlyphView.GlyphPainter p)

Sets the painter to use for rendering glyphs.

Parameters:

p - the painter to use for rendering glyphs

getText

public Segment getText(int p0,
 int p1)

Fetch a reference to the text that occupies the given range. This is normally used by the GlyphPainter to determine what characters it should render glyphs for.

Parameters:

p0 - the starting document offset >= 0

p1 - the ending document offset >= p0

Returns:

the Segment containing the text

getBackground

public Color getBackground()

Fetch the background color to use to render the glyphs. If there is no background color, null should be returned. This is implemented to call StyledDocument.getBackground if the associated document is a styled document, otherwise it returns null.

Returns:

the background color to use to render the glyphs

getForeground

public Color getForeground()

Fetch the foreground color to use to render the glyphs. If there is no foreground color, null should be returned. This is implemented to call StyledDocument.getBackground if the associated document is a StyledDocument. If the associated document is not a StyledDocument, the associated components foreground color is used. If there is no associated component, null is returned.

Returns:

the foreground color to use to render the glyphs

getFont

public Font getFont()

Fetch the font that the glyphs should be based upon. This is implemented to call StyledDocument.getFont if the associated document is a StyledDocument. If the associated document is not a StyledDocument, the associated components font is used. If there is no associated component, null is returned.

Returns:

the font that the glyphs should be based upon

isUnderline

public boolean isUnderline()

Determine if the glyphs should be underlined. If true, an underline should be drawn through the baseline.

Returns:

if the glyphs should be underlined

isStrikeThrough

public boolean isStrikeThrough()

Determine if the glyphs should have a strikethrough line. If true, a line should be drawn through the center of the glyphs.

Returns:

if the glyphs should have a strikethrough line

isSubscript

public boolean isSubscript()

Determine if the glyphs should be rendered as superscript.

Returns:

if the glyphs should be rendered as superscript

isSuperscript

public boolean isSuperscript()

Determine if the glyphs should be rendered as subscript.

Returns:

if the glyphs should be rendered as subscript

getTabExpander

public TabExpander getTabExpander()

Fetch the TabExpander to use if tabs are present in this view.

Returns:

the TabExpander to use if tabs are present in this view

checkPainter

protected void checkPainter()

Check to see that a glyph painter exists. If a painter doesn't exist, a default glyph painter will be installed.

getTabbedSpan

public float getTabbedSpan(float x,
 TabExpander e)

Determines the desired span when using the given tab expansion implementation.

Specified by:

getTabbedSpan in interface TabableView

Parameters:

x - the position the view would be located at for the purpose of tab expansion >= 0.

e - how to expand the tabs when encountered.

Returns:

the desired span >= 0

See Also:

TabableView.getTabbedSpan(float, javax.swing.text.TabExpander)

getPartialSpan

public float getPartialSpan(int p0,
 int p1)

Determines the span along the same axis as tab expansion for a portion of the view. This is intended for use by the TabExpander for cases where the tab expansion involves aligning the portion of text that doesn't have whitespace relative to the tab stop. There is therefore an assumption that the range given does not contain tabs.

This method can be called while servicing the getTabbedSpan or getPreferredSize. It has to arrange for its own text buffer to make the measurements.

Specified by:

getPartialSpan in interface TabableView

Parameters:

p0 - the starting document offset >= 0

p1 - the ending document offset >= p0

Returns:

the span >= 0

getStartOffset

public int getStartOffset()

Fetches the portion of the model that this view is responsible for.

Overrides:

getStartOffset in class View

Returns:

the starting offset into the model

See Also:

View.getStartOffset()

getEndOffset

public int getEndOffset()

Fetches the portion of the model that this view is responsible for.

Overrides:

getEndOffset in class View

Returns:

the ending offset into the model

See Also:

View.getEndOffset()

paint

public void paint(Graphics g,