public class ParagraphView extends FlowView implements TabExpander
View of a simple line-wrapping paragraph that supports multiple fonts, colors, components, icons, etc. It is basically a vertical box with a margin around it. The contents of the box are a bunch of rows which are special horizontal boxes. This view creates a collection of views that represent the child elements of the paragraph element. Each of these views are placed into a row directly if they will fit, otherwise the breakView
method is called to try and carve the view into pieces that fit.
View
FlowView.FlowStrategy
protected int firstLineIndent
Indentation for the first line, from the left inset.
public ParagraphView(Element elem)
Constructs a ParagraphView
for the given element.
elem
- the element that this view is responsible forprotected void setJustification(int j)
Sets the type of justification.
j
- one of the following values: StyleConstants.ALIGN_LEFT
StyleConstants.ALIGN_CENTER
StyleConstants.ALIGN_RIGHT
protected void setLineSpacing(float ls)
Sets the line spacing.
ls
- the value is a factor of the line hightprotected void setFirstLineIndent(float fi)
Sets the indent on the first line.
fi
- the value in pointsprotected void setPropertiesFromAttributes()
Set the cached properties from the attributes.
protected int getLayoutViewCount()
Returns the number of views that this view is responsible for. The child views of the paragraph are rows which have been used to arrange pieces of the View
s that represent the child elements. This is the number of views that have been tiled in two dimensions, and should be equivalent to the number of child elements to the element this view is responsible for.
ParagraphView
is responsible forprotected View getLayoutView(int index)
Returns the view at a given index
. The child views of the paragraph are rows which have been used to arrange pieces of the Views
that represent the child elements. This methods returns the view responsible for the child element index (prior to breaking). These are the Views that were produced from a factory (to represent the child elements) and used for layout.
index
- the index
of the desired viewindex
protected int getNextNorthSouthVisualPositionFrom(int pos, Position.Bias b, Shape a, int direction, Position.Bias[] biasRet) throws BadLocationException
Returns the next visual position for the cursor, in either the east or west direction. Overridden from CompositeView
.
getNextNorthSouthVisualPositionFrom
in class CompositeView
pos
- position into the modelb
- either Position.Bias.Forward
or Position.Bias.Backward
a
- the allocated region to render intodirection
- either SwingConstants.NORTH
or SwingConstants.SOUTH
biasRet
- an array containing the bias that were checked in this methodBadLocationException
CompositeView.getNextVisualPositionFrom(int, javax.swing.text.Position.Bias, java.awt.Shape, int, javax.swing.text.Position.Bias[])
protected int getClosestPositionTo(int pos, Position.Bias b, Shape a, int direction, Position.Bias[] biasRet, int rowIndex, int x) throws BadLocationException
Returns the closest model position to x
. rowIndex
gives the index of the view that corresponds that should be looked in.
pos
- position into the modela
- the allocated region to render intodirection
- one of the following values: SwingConstants.NORTH
SwingConstants.SOUTH
biasRet
- an array containing the bias that were checked in this methodrowIndex
- the index of the viewx
- the x coordinate of interestx
BadLocationException
protected boolean flipEastAndWestAtEnds(int position, Position.Bias bias)
Determines in which direction the next view lays. Consider the View
at index n. Typically the View
s are layed out from left to right, so that the View
to the EAST will be at index n + 1, and the View
to the WEST will be at index n - 1. In certain situations, such as with bidirectional text, it is possible that the View
to EAST is not at index n + 1, but rather at index n - 1, or that the View
to the WEST is not at index n - 1, but index n + 1. In this case this method would return true, indicating the View
s are layed out in descending order.
This will return true if the text is layed out right to left at position, otherwise false.
flipEastAndWestAtEnds
in class BoxView
position
- position into the modelbias
- either Position.Bias.Forward
or Position.Bias.Backward
public int getFlowSpan(int index)
Fetches the constraining span to flow against for the given child index.
getFlowSpan
in class FlowView
index
- the index of the view being queriedindex
FlowView.getFlowStart(int)
public int getFlowStart(int index)
Fetches the location along the flow axis that the flow span will start at.
getFlowStart
in class FlowView
index
- the index of the view being queriedindex
FlowView.getFlowSpan(int)
protected View createRow()
Create a View
that should be used to hold a a row's worth of children in a flow.
public float nextTabStop(float x, int tabOffset)
Returns the next tab stop position given a reference position. This view implements the tab coordinate system, and calls getTabbedSpan
on the logical children in the process of layout to determine the desired span of the children. The logical children can delegate their tab expansion upward to the paragraph which knows how to expand tabs. LabelView
is an example of a view that delegates its tab expansion needs upward to the paragraph.
This is implemented to try and locate a TabSet
in the paragraph element's attribute set. If one can be found, its settings will be used, otherwise a default expansion will be provided. The base location for for tab expansion is the left inset from the paragraphs most recent allocation (which is what the layout of the children is based upon).
nextTabStop
in interface TabExpander
x
- the X reference positiontabOffset
- the position within the text stream that the tab occurred at >= 0TabSet
, TabStop
, LabelView
protected TabSet getTabSet()
Gets the Tabset
to be used in calculating tabs.
TabSet
protected float getPartialSize(int startOffset, int endOffset)
Returns the size used by the views between startOffset
and endOffset
. This uses getPartialView
to calculate the size if the child view implements the TabableView
interface. If a size is needed and a View
does not implement the TabableView
interface, the preferredSpan
will be used.
startOffset
- the starting document offset >= 0endOffset
- the ending document offset >= startOffsetprotected int findOffsetToCharactersInString(char[] string, int start)
Finds the next character in the document with a character in string
, starting at offset start
. If there are no characters found, -1 will be returned.
string
- the string of charactersstart
- where to start in the model >= 0protected float getTabBase()
Returns where the tabs are calculated from.
public void paint(Graphics g, Shape a)
Renders using the given rendering surface and area on that surface. This is implemented to delegate to the superclass after stashing the base coordinate for tab calculations.
paint
in class BoxView
g
- the rendering surface to usea
- the allocated region to render intoView.paint(java.awt.Graphics, java.awt.Shape)
public float getAlignment(int axis)
Determines the desired alignment for this view along an axis. This is implemented to give the alignment to the center of the first row along the y axis, and the default along the x axis.
getAlignment
in class BoxView
axis
- may be either View.X_AXIS
or View.Y_AXIS
public View breakView(int axis, float len, Shape a)
Breaks this view on the given axis at the given length.
ParagraphView
instances are breakable along the Y_AXIS
only, and only if len
is after the first line.
axis
- may be either View.X_AXIS
or View.Y_AXIS
len
- specifies where a potential break is desired along the given axis >= 0a
- the current allocation of the viewView.breakView(int, int, float, float)
public int getBreakWeight(int axis, float len)
Gets the break weight for a given location.
ParagraphView
instances are breakable along the Y_AXIS
only, and only if len
is after the first row. If the length is less than one row, a value of BadBreakWeight
is returned.
axis
- may be either View.X_AXIS
or View.Y_AXIS
len
- specifies where a potential break is desired >= 0GoodBreakWeight
or BadBreakWeight
View.getBreakWeight(int, float, float)
protected SizeRequirements calculateMinorAxisRequirements(int axis, SizeRequirements r)
Calculate the needs for the paragraph along the minor axis.
This uses size requirements of the superclass, modified to take into account the non-breakable areas at the adjacent views edges. The minimal size requirements for such views should be no less than the sum of all adjacent fragments.
If the axis
parameter is neither View.X_AXIS
nor View.Y_AXIS
, IllegalArgumentException
is thrown. If the r
parameter is null,
a new SizeRequirements
object is created, otherwise the supplied SizeRequirements
object is returned.
calculateMinorAxisRequirements
in class FlowView
axis
- the minor axisr
- the input SizeRequirements
objectSizeRequirements
objectIllegalArgumentException
- if the axis
parameter is invalidSizeRequirements
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.
changedUpdate
in class FlowView
changes
- the change information from the associated documenta
- the current allocation of the viewf
- the factory to use to rebuild if the view has childrenView.changedUpdate(javax.swing.event.DocumentEvent, java.awt.Shape, javax.swing.text.ViewFactory)
© 1993–2017, 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.