Class WrappedPlainView

All Implemented Interfaces:
SwingConstants, TabExpander 

public class WrappedPlainView
extends BoxView
implements TabExpander

View of plain text (text with only one font and color) that does line-wrapping. This view expects that its associated element has child elements that represent the lines it should be wrapping. It is implemented as a vertical box that contains logical line views. The logical line views are nested classes that render the logical line as multiple physical line if the logical line is too wide to fit within the allocation. The line views draw upon the outer class for its state to reduce their memory requirements.

The line views do all of their rendering through the drawLine method which in turn does all of its rendering through the drawSelectedText and drawUnselectedText methods. This enables subclasses to easily specialize the rendering without concern for the layout aspects.

See Also:
View

Fields

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

Constructors

Constructor and Description
WrappedPlainView(Element elem)

Creates a new WrappedPlainView.
WrappedPlainView(Element elem, boolean wordWrap)

Creates a new WrappedPlainView.

Methods

Modifier and Type Method and Description
protected int calculateBreakPosition(int p0, int p1)

This is called by the nested wrapped line views to determine the break location.
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 drawLine(int p0, int p1, 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.
protected Segment getLineBuffer()

Gives access to a buffer that can be used to fetch text from the associated document.
float getMaximumSpan(int axis)

Determines the maximum span for this view along an axis.
float getMinimumSpan(int axis)

Determines the minimum span for this view along an axis.
float getPreferredSpan(int axis)

Determines the preferred span for this view along an axis.
protected int getTabSize()

Returns the tab size set for the document, defaulting to 8.
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.
protected void loadChildren(ViewFactory f)

Loads all of the children to initialize the view.
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 e, 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.

Methods inherited from class javax.swing.text.BoxView

baselineLayout, baselineRequirements, calculateMajorAxisRequirements, calculateMinorAxisRequirements, childAllocation, flipEastAndWestAtEnds, forwardUpdate, getAlignment, getAxis, getChildAllocation, getHeight, getOffset, getResizeWeight, getSpan, getViewAtPoint, getWidth, isAfter, isAllocationValid, isBefore, isLayoutValid, layout, layoutChanged, layoutMajorAxis, layoutMinorAxis, modelToView, paintChild, preferenceChanged, replace, setAxis, viewToModel

Methods inherited from class javax.swing.text.CompositeView

getBottomInset, getInsideAllocation, getLeftInset, getNextEastWestVisualPositionFrom, getNextNorthSouthVisualPositionFrom, getNextVisualPositionFrom, getRightInset, getTopInset, getView, getViewAtPosition, getViewCount, getViewIndex, getViewIndexAtPosition, modelToView, setInsets, setParagraphInsets, setParent

Methods inherited from class javax.swing.text.View

append, breakView, createFragment, forwardUpdateToView, getAttributes, getBreakWeight, getContainer, getDocument, getElement, getEndOffset, getGraphics, getParent, getStartOffset, getToolTipText, getViewFactory, getViewIndex, insert, isVisible, modelToView, remove, removeAll, updateChildren, updateLayout, viewToModel

Methods inherited from class java.lang.Object

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

Constructors

WrappedPlainView

public WrappedPlainView(Element elem)

Creates a new WrappedPlainView. Lines will be wrapped on character boundaries.

Parameters:
elem - the element underlying the view

WrappedPlainView

public WrappedPlainView(Element elem,
                        boolean wordWrap)

Creates a new WrappedPlainView. Lines can be wrapped on either character or word boundaries depending upon the setting of the wordWrap parameter.

Parameters:
elem - the element underlying the view
wordWrap - should lines be wrapped on word boundaries?

Methods

getTabSize

protected int getTabSize()

Returns the tab size set for the document, defaulting to 8.

Returns:
the tab size

drawLine

protected void drawLine(int p0,
                        int p1,
                        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.

Parameters:
p0 - the starting document location to use >= 0
p1 - the ending document location to use >= p1
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)

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.

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 >= p0
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.

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 >= p0
Returns:
the location of the end of the range.
Throws:
BadLocationException - if the range is invalid

getLineBuffer

protected final Segment getLineBuffer()

Gives access to a buffer that can be used to fetch text from the associated document.

Returns:
the buffer

calculateBreakPosition

protected int calculateBreakPosition(int p0,
                                     int p1)

This is called by the nested wrapped line views to determine the break location. This can be reimplemented to alter the breaking behavior. It will either break at word or character boundaries depending upon the break argument given at construction.

loadChildren

protected void loadChildren(ViewFactory f)

Loads all of the children to initialize the view. This is called by the setParent method. Subclasses can reimplement this to initialize their child views in a different manner. The default implementation creates a child view for each child element.

Overrides:
loadChildren in class CompositeView
Parameters:
f - the view factory
See Also:
CompositeView.setParent(javax.swing.text.View)

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
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

paint

public void paint(Graphics g,
                  Shape a)

Renders using the given rendering surface and area on that surface. This is implemented to stash the selection positions, selection colors, and font metrics for the nested lines to use.

Overrides:
paint in class BoxView
Parameters:
g - the rendering surface to use
a - the allocated region to render into
See Also:
View.paint(java.awt.Graphics, java.awt.Shape)

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 BoxView
Parameters:
width - the width >= 0
height - the height >= 0

getPreferredSpan

public float getPreferredSpan(int axis)

Determines the preferred span for this view along an axis. This is implemented to provide the superclass behavior after first making sure that the current font metrics are cached (for the nested lines which use the metrics to determine the height of the potentially wrapped lines).

Overrides:
getPreferredSpan in class BoxView
Parameters:
axis - may be either View.X_AXIS or View.Y_AXIS
Returns:
the span the view would like to be rendered into. 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.
See Also:
View.getPreferredSpan(int)

getMinimumSpan

public float getMinimumSpan(int axis)

Determines the minimum span for this view along an axis. This is implemented to provide the superclass behavior after first making sure that the current font metrics are cached (for the nested lines which use the metrics to determine the height of the potentially wrapped lines).

Overrides:
getMinimumSpan in class BoxView
Parameters:
axis - may be either View.X_AXIS or View.Y_AXIS
Returns:
the span the view would like to be rendered into. 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.
See Also:
View.getMinimumSpan(int)

getMaximumSpan

public float getMaximumSpan(int axis)

Determines the maximum span for this view along an axis. This is implemented to provide the superclass behavior after first making sure that the current font metrics are cached (for the nested lines which use the metrics to determine the height of the potentially wrapped lines).

Overrides:
getMaximumSpan in class BoxView
Parameters:
axis - may be either View.X_AXIS or View.Y_AXIS
Returns:
the span the view would like to be rendered into. 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.
See Also:
View.getMaximumSpan(int)

insertUpdate

public 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. This is implemented to simply update the children.

Overrides:
insertUpdate in class View
Parameters:
e - 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 e,
                         Shape a,
                         ViewFactory f)

Gives notification that something was removed from the document in a location that this view is responsible for. This is implemented to simply update the children.

Overrides:
removeUpdate in class View
Parameters:
e - 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 e,
                          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 View
Parameters:
e - 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)

© 1993, 2020, Oracle and/or its affiliates. All rights reserved.
Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Various third party code in OpenJDK is licensed under different licenses (see Debian package).
Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.
https://docs.oracle.com/javase/8/docs/api/javax/swing/text/WrappedPlainView.html