org.bounce.text

Class FoldingPlainView

java.lang.Object

javax.swing.text.View

javax.swing.text.PlainView

org.bounce.text.FoldingPlainView

All Implemented Interfaces:

SwingConstants, TabExpander

Direct Known Subclasses:

SyntaxHighlightingView

public class FoldingPlainView
extends PlainView

Implements View interface for a simple multi-line text view that has text in one font and color. The view represents each child element as a line of text.

Version:

1.71 01/23/03

Author:

Timothy Prinzing

See Also:

View

Field Summary

Fields

Modifier and Type	Field and Description
protected FontMetrics	metrics Font metrics for the current font.

Fields inherited from class javax.swing.text.View

BadBreakWeight, ExcellentBreakWeight, ForcedBreakWeight, GoodBreakWeight, X_AXIS, Y_AXIS

Fields inherited from 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 and Description
FoldingPlainView(Element elem) Constructs a new PlainView wrapped on an element.

Method Summary

Methods

Modifier and Type	Method and Description
void	calculateLongestLine() Iterate over the lines represented by the child elements of the element this view represents, looking for the line that is the longest.
void	changedUpdate(DocumentEvent changes, Shape a, ViewFactory f) Gives notification from the document that attributes were changed in a location that this view is responsible for.
protected void	damageLineRange(int line0, int line1, Shape a, Component host) Repaint the given line range.
protected void	drawLine(int lineIndex, Graphics g, int x, int y) Renders a line of text, suppressing whitespace at the end and expanding any tabs.
protected int	drawSelectedText(Graphics g, int x, int y, int p0, int p1) Renders the given range in the model as selected text.
protected int	drawUnselectedText(Graphics g, int x, int y, int p0, int p1) Renders the given range in the model as normal unselected text.
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 at which one might place a caret.
float	getPreferredSpan(int axis) Determines the preferred span for this view along an axis.
void	insertUpdate(DocumentEvent changes, Shape a, ViewFactory f) Gives notification that something was inserted into the document in a location that this view is responsible for.
protected Rectangle	lineToRect(Shape a, int line) Determine the rectangle that represents the given line.
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.
float	nextTabStop(float x, int tabOffset) Returns the next tab stop position after a given reference position.
void	paint(Graphics g, Shape a) Renders using the given rendering surface and area on that surface.
void	removeUpdate(DocumentEvent changes, Shape a, ViewFactory f) Gives notification that something was removed from the document in a location that this view is responsible for.
void	setSize(float width, float height) Sets the size of the view.
protected void	updateDamage(DocumentEvent changes, Shape a, ViewFactory f)
protected void	updateMetrics() Checks to see if the font metrics and longest line are up-to-date.
int	viewToModel(float fx, float fy, Shape a, Position.Bias[] bias) Provides a mapping from the view coordinate space to the logical coordinate space of the model.

Methods inherited from class javax.swing.text.PlainView

getLineBuffer, getTabSize

Methods inherited from class javax.swing.text.View

append, breakView, createFragment, forwardUpdate, forwardUpdateToView, getAlignment, getAttributes, getBreakWeight, getChildAllocation, getContainer, getDocument, getElement, getEndOffset, getGraphics, getMaximumSpan, getMinimumSpan, getParent, getResizeWeight, getStartOffset, getToolTipText, getView, getViewCount, getViewFactory, getViewIndex, getViewIndex, insert, isVisible, modelToView, modelToView, preferenceChanged, remove, removeAll, replace, setParent, updateChildren, updateLayout, viewToModel

Methods inherited from class java.lang.Object

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

Field Detail

metrics

protected FontMetrics metrics

Font metrics for the current font.

Constructor Detail

FoldingPlainView

public FoldingPlainView(Element elem)

Constructs a new PlainView wrapped on an element.

Parameters:

elem - the element

Method Detail

drawLine

protected void drawLine(int lineIndex,
            Graphics g,
            int x,
            int y)

Renders a line of text, suppressing whitespace at the end and expanding any tabs. This is implemented to make calls to the methods drawUnselectedText and drawSelectedText so that the way selected and unselected text are rendered can be customized.

Overrides:

drawLine in class PlainView

Parameters:

lineIndex - the line to draw >= 0

g - the Graphics context

x - the starting X position >= 0

y - the starting Y position >= 0

See Also:

drawUnselectedText(java.awt.Graphics, int, int, int, int), drawSelectedText(java.awt.Graphics, int, int, int, int)

getNextVisualPositionFrom

public int getNextVisualPositionFrom(int pos,
                            Position.Bias b,
                            Shape a,
                            int direction,
                            Position.Bias[] biasRet)
                              throws BadLocationException

Provides a way to determine the next visually represented model location at which one might place a caret. Some views may not be visible, they might not be in the same order found in the model, or they just might not allow access to some of the locations in the model.

Overrides:

getNextVisualPositionFrom in class View

Parameters:

pos - the position to convert >= 0

a - the allocated region in which to render

direction - the direction from the current position that can be thought of as the arrow keys typically found on a keyboard. This will be one of the following values:

• SwingConstants.WEST
• SwingConstants.EAST
• SwingConstants.NORTH
• SwingConstants.SOUTH

Returns:

the location within the model that best represents the next location visual position

Throws:

BadLocationException

IllegalArgumentException - if direction doesn't have one of the legal values above

drawUnselectedText

protected int drawUnselectedText(Graphics g,
                     int x,
                     int y,
                     int p0,
                     int p1)
                          throws BadLocationException

Renders the given range in the model as normal unselected text. Uses the foreground or disabled color to render the text.

Overrides:

drawUnselectedText in class PlainView

Parameters:

g - the graphics context

x - the starting X coordinate >= 0

y - the starting Y coordinate >= 0

p0 - the beginning position in the model >= 0

p1 - the ending position in the model >= 0

Returns:

the X location of the end of the range >= 0

Throws:

BadLocationException - if the range is invalid

drawSelectedText

protected int drawSelectedText(Graphics g,
                   int x,
                   int y,
                   int p0,
                   int p1)
                        throws BadLocationException

Renders the given range in the model as selected text. This is implemented to render the text in the color specified in the hosting component. It assumes the highlighter will render the selected background.

Overrides:

drawSelectedText in class PlainView

Parameters:

g - the graphics context

x - the starting X coordinate >= 0

y - the starting Y coordinate >= 0

p0 - the beginning position in the model >= 0

p1 - the ending position in the model >= 0

Returns:

the location of the end of the range

Throws:

BadLocationException - if the range is invalid

updateMetrics

protected void updateMetrics()

Checks to see if the font metrics and longest line are up-to-date.

Overrides:

updateMetrics in class PlainView

Since:

1.4

getPreferredSpan

public float getPreferredSpan(int axis)

Determines the preferred span for this view along an axis.

Overrides:

getPreferredSpan in class PlainView

Parameters:

axis - may be either View.X_AXIS or View.Y_AXIS

Returns:

the span the view would like to be rendered into >= 0. Typically the view is told to render into the span that is returned, although there is no guarantee. The parent may choose to resize or break the view.

Throws:

IllegalArgumentException - for an invalid axis

paint

public void paint(Graphics g,
         Shape a)

Renders using the given rendering surface and area on that surface. The view may need to do layout and create child views to enable itself to render into the given allocation.

Overrides:

paint in class PlainView

Parameters:

g - the rendering surface to use

a - the allocated region to render into

See Also:

View.paint(java.awt.Graphics, java.awt.Shape)

modelToView

public Shape modelToView(int pos,
                Shape a,
                Position.Bias b)
                  throws BadLocationException

Provides a mapping from the document model coordinate space to the coordinate space of the view mapped to it.

Overrides:

modelToView in class PlainView

Parameters:

pos - the position to convert >= 0

a - the allocated region to render into

Returns:

the bounding box of the given position

Throws:

BadLocationException - if the given position does not represent a valid location in the associated document

See Also:

View.modelToView(int, java.awt.Shape, javax.swing.text.Position.Bias)

viewToModel

public int viewToModel(float fx,
              float fy,
              Shape a,
              Position.Bias[] bias)

Provides a mapping from the view coordinate space to the logical coordinate space of the model.

Overrides:

viewToModel in class PlainView

Parameters:

fx - the X coordinate >= 0

fy - the Y coordinate >= 0

a - the allocated region to render into

Returns:

the location within the model that best represents the given point in the view >= 0

See Also:

View.viewToModel(float, float, java.awt.Shape, javax.swing.text.Position.Bias[])

insertUpdate

public void insertUpdate(DocumentEvent changes,
                Shape a,
                ViewFactory f)

Gives notification that something was inserted into the document in a location that this view is responsible for.

Overrides:

insertUpdate in class PlainView

Parameters:

changes - the change information from the associated document

a - the current allocation of the view

f - the factory to use to rebuild if the view has children

See Also:

View.insertUpdate(javax.swing.event.DocumentEvent, java.awt.Shape, javax.swing.text.ViewFactory)

removeUpdate

public void removeUpdate(DocumentEvent changes,
                Shape a,
                ViewFactory f)

Gives notification that something was removed from the document in a location that this view is responsible for.

Overrides:

removeUpdate in class PlainView

Parameters:

changes - the change information from the associated document

a - the current allocation of the view

f - the factory to use to rebuild if the view has children

See Also:

View.removeUpdate(javax.swing.event.DocumentEvent, java.awt.Shape, javax.swing.text.ViewFactory)

changedUpdate

public void changedUpdate(DocumentEvent changes,
                 Shape a,
                 ViewFactory f)

Gives notification from the document that attributes were changed in a location that this view is responsible for.

Overrides:

changedUpdate in class PlainView

Parameters:

changes - the change information from the associated document

a - the current allocation of the view

f - the factory to use to rebuild if the view has children

See Also:

View.changedUpdate(javax.swing.event.DocumentEvent, java.awt.Shape, javax.swing.text.ViewFactory)

setSize

public void setSize(float width,
           float height)

Sets the size of the view. This should cause layout of the view along the given axis, if it has any layout duties.

Overrides:

setSize in class PlainView

Parameters:

width - the width >= 0

height - the height >= 0

nextTabStop

public float nextTabStop(float x,
                int tabOffset)

Returns the next tab stop position after a given reference position. This implementation does not support things like centering so it ignores the tabOffset argument.

Specified by:

nextTabStop in interface TabExpander

Overrides:

nextTabStop in class PlainView

Parameters:

x - the current position >= 0

tabOffset - the position within the text stream that the tab occurred at >= 0.

Returns:

the tab stop, measured in points >= 0

updateDamage

protected void updateDamage(DocumentEvent changes,
                Shape a,
                ViewFactory f)

Overrides:

updateDamage in class PlainView

damageLineRange

protected void damageLineRange(int line0,
                   int line1,
                   Shape a,
                   Component host)

Repaint the given line range.

Overrides:

damageLineRange in class PlainView

Parameters:

host - the component hosting the view (used to call repaint)

a - the region allocated for the view to render into

line0 - the starting line number to repaint. This must be a valid line number in the model.

line1 - the ending line number to repaint. This must be a valid line number in the model.

Since:

1.4

lineToRect

protected Rectangle lineToRect(Shape a,
                   int line)

Determine the rectangle that represents the given line.

Overrides:

lineToRect in class PlainView

Parameters:

a - the region allocated for the view to render into

line - the line number to find the region of. This must be a valid line number in the model.

Since:

1.4

calculateLongestLine

public void calculateLongestLine()

Iterate over the lines represented by the child elements of the element this view represents, looking for the line that is the longest. The longLine variable is updated to represent the longest line contained. The font variable is updated to indicate the font used to calculate the longest line.