java.lang.Object | +--javax.swing.text.View | +--javax.swing.text.CompositeView | +--javax.swing.text.BoxView
Safe: A view that arranges its children into a box shape by tiling its children along an axis. The box is somewhat like that found in TeX where there is alignment of the children, flexibility of the children is considered, etc. This is a building block that might be useful to represent things like a collection of lines, paragraphs, lists, columns, pages, etc. The axis along which the children are tiled is considered the major axis. The orthoginal axis is the minor axis.
Layout for each axis is handled separately by the methods
layoutMajorAxis and layoutMinorAxis.
Subclasses can change the layout algorithm by
reimplementing these methods. These methods will be called
as necessary depending upon whether or not there is cached
layout information and the cache is considered
valid. These methods are typically called if the given size
along the axis changes, or if layoutChanged is
called to force an updated layout. The layoutChanged
method invalidates cached layout information, if there is any.
The requirements published to the parent view are calculated by
the methods calculateMajorAxisRequirements
and calculateMinorAxisRequirements.
If the layout algorithm is changed, these methods will
likely need to be reimplemented.
BadBreakWeight, ExcellentBreakWeight, ForcedBreakWeight, GoodBreakWeight, sharedBiasReturn, X_AXIS, Y_AXIS
BOTTOM, CENTER, EAST, HORIZONTAL, LEADING, LEFT, NEXT, NORTH, NORTH_EAST, NORTH_WEST, PREVIOUS, RIGHT, SOUTH, SOUTH_EAST, SOUTH_WEST, TOP, TRAILING, VERTICAL, WEST
protected void
baselineLayout(int targetSpan,
int axis,
int[] offsets,
int[] spans)
BoxView given the targetSpan,
which is the width (or height) of the region we have to
work with.
protected SizeRequirements
baselineRequirements(int axis,
SizeRequirements r)
BoxView
by examining the size of each child view.
protected SizeRequirements
calculateMajorAxisRequirements(int axis,
SizeRequirements r)
protected SizeRequirements
calculateMinorAxisRequirements(int axis,
SizeRequirements r)
axis.
protected boolean
flipEastAndWestAtEnds(int position,
javax.swing.text.Position.Bias bias)
protected void
forwardUpdate(javax.swing.event.DocumentEvent.ElementChange ec,
DocumentEvent e,
Shape a,
ViewFactory f)
DocumentEvent to the child views
that need to be notified of the change to the model.
Shape
getChildAllocation(int index,
Shape a)
protected int
getOffset(int axis,
int childIndex)
float
getPreferredSpan(int axis)
protected int
getSpan(int axis,
int childIndex)
protected View
getViewAtPoint(int x,
int y,
Rectangle alloc)
protected boolean
isAfter(int x,
int y,
Rectangle innerAlloc)
protected boolean
isBefore(int x,
int y,
Rectangle innerAlloc)
protected void
layoutMajorAxis(int targetSpan,
int axis,
int[] offsets,
int[] spans)
protected void
layoutMinorAxis(int targetSpan,
int axis,
int[] offsets,
int[] spans)
Shape
modelToView(int pos,
Shape a,
javax.swing.text.Position.Bias b)
void
paint(Graphics g,
Shape allocation)
BoxView using the given
rendering surface and area
on that surface.
void
preferenceChanged(View child,
boolean width,
boolean height)
void
replace(int index,
int length,
View[] elems)
(package private) int[]
updateLayoutArray(int[] oldArray,
int offset,
int nInserted)
int
viewToModel(float x,
float y,
Shape a,
javax.swing.text.Position.Bias[] bias)
getBottomInset, getInsideAllocation, getLeftInset, getNextEastWestVisualPositionFrom, getNextNorthSouthVisualPositionFrom, getNextVisualPositionFrom, getRightInset, getTopInset, getView, getViewAtPosition, getViewCount, getViewIndex, getViewIndexAtPosition, loadChildren, modelToView, setInsets, setParagraphInsets, setParent
append, breakView, changedUpdate, createFragment, forwardUpdateToView, getAttributes, getBreakWeight, getContainer, getDocument, getElement, getEndOffset, getGraphics, getParent, getStartOffset, getToolTipText, getViewFactory, getViewIndex, insert, insertUpdate, isVisible, modelToView, remove, removeAll, removeUpdate, updateChildren, updateLayout, viewToModel
int majorAxis
int majorSpan
int minorSpan
boolean majorReqValid
boolean minorReqValid
SizeRequirements majorRequest
SizeRequirements minorRequest
boolean majorAllocValid
int[] majorOffsets
int[] majorSpans
boolean minorAllocValid
int[] minorOffsets
int[] minorSpans
Rectangle tempRect
public BoxView(Element elem, int axis)
BoxView.
elem - the element this view is responsible foraxis - either View.X_AXIS or View.Y_AXISpublic int getAxis()
View.X_AXIS or View.Y_AXISpublic void setAxis(int axis)
axis - either View.X_AXIS or View.Y_AXISpublic void layoutChanged(int axis)
setSize method
is called on this view (typically in paint).
axis - either View.X_AXIS or View.Y_AXISprotected boolean isLayoutValid(int axis)
axis - either View.X_AXIS or View.Y_AXISprotected void paintChild(Graphics g, Rectangle alloc, int index)
g - the graphics contextalloc - the allocated region to paint intoindex - the child index,>= 0 && < getViewCount()public void replace(int index, int length, View[] elems)
replace in class CompositeViewindex - the starting index into the child views to insert
the new views; this should be a value>= 0 and <= getViewCountlength - the number of existing child views to remove;
This should be a value>= 0 and <= (getViewCount() - offset)elems - the child views to add; this value can be
null
to indicate no children are being added (useful to remove)int[] updateLayoutArray(int[] oldArray, int offset, int nInserted)
oldArray - the original layout arrayoffset - location where new views will be insertednInserted - the number of child views being inserted;
therefore the number of blank spaces to leave in the
new array at location offset
protected void forwardUpdate(javax.swing.event.DocumentEvent.ElementChange ec, DocumentEvent e, Shape a, ViewFactory f)
DocumentEvent to the child views
that need to be notified of the change to the model.
If a child changed its requirements and the allocation
was valid prior to forwarding the portion of the box
from the starting child to the end of the box will
be repainted.
forwardUpdate in class Viewec - changes to the element this view is responsible
for (may be null if there were no changes)e - the change information from the associated documenta - the current allocation of the viewf - the factory to use to rebuild if the view has childrenView.insertUpdate(javax.swing.event.DocumentEvent, java.awt.Shape, javax.swing.text.ViewFactory),
View.removeUpdate(javax.swing.event.DocumentEvent, java.awt.Shape, javax.swing.text.ViewFactory),
View.changedUpdate(javax.swing.event.DocumentEvent, java.awt.Shape, javax.swing.text.ViewFactory)public void preferenceChanged(View child, boolean width, boolean height)
preferenceChanged in class Viewchild - the child viewwidth - true if the width preference should changeheight - true if the height preference should changejavax.swing.JComponent#revalidatepublic int getResizeWeight(int axis)
getResizeWeight in class Viewaxis - may be either View.X_AXIS or
View.Y_AXIS
void setSpanOnAxis(int axis, float span)
axis - may be either View.X_AXIS or
View.Y_AXISspan - the span to layout to>= 0void updateChildSizes()
float getSpanOnAxis(int axis)
axis - may be either View.X_AXIS or
View.Y_AXIS
public void setSize(float width, float height)
width - the width>= 0height - the height>= 0public void paint(Graphics g, Shape allocation)
BoxView using the given
rendering surface and area
on that surface. Only the children that intersect
the clip bounds of the given Graphics
will be rendered.
g - the rendering surface to useallocation - the allocated region to render intoView.paint(java.awt.Graphics, java.awt.Shape)public Shape getChildAllocation(int index, Shape a)
null if the layout is invalid,
otherwise the superclass behavior is executed.
getChildAllocation in class CompositeViewindex - the index of the child,>= 0 && < getViewCount()a - the allocation to this view
null
if a is null;
or null if the layout is invalidpublic Shape modelToView(int pos, Shape a, javax.swing.text.Position.Bias b) throws BadLocationException
modelToView in class CompositeViewpos - the position to convert>= 0a - the allocated region to render intob - a bias value of either Position.Bias.Forward
or Position.Bias.Backward
BadLocationExceptionView.modelToView(int, java.awt.Shape, javax.swing.text.Position.Bias)public int viewToModel(float x, float y, Shape a, javax.swing.text.Position.Bias[] bias)
viewToModel in class CompositeViewx - x coordinate of the view location to convert>= 0y - y coordinate of the view location to convert>= 0a - the allocated region to render intobias - either Position.Bias.Forward or
Position.Bias.Backward
View.viewToModel(float, float, java.awt.Shape, javax.swing.text.Position.Bias[])public float getAlignment(int axis)
getAlignment in class Viewaxis - may be either View.X_AXIS
or View.Y_AXIS
public float getPreferredSpan(int axis)
getPreferredSpan in class Viewaxis - may be either View.X_AXIS
or View.Y_AXIS
View.getPreferredSpan(int)public float getMinimumSpan(int axis)
getMinimumSpan in class Viewaxis - may be either View.X_AXIS
or View.Y_AXIS
View.getPreferredSpan(int)public float getMaximumSpan(int axis)
getMaximumSpan in class Viewaxis - may be either View.X_AXIS
or View.Y_AXIS
View.getPreferredSpan(int)protected boolean isAllocationValid()
protected boolean isBefore(int x, int y, Rectangle innerAlloc)
isBefore in class CompositeViewx - the X coordinate>= 0y - the Y coordinate>= 0innerAlloc - the allocated region; this is the area
inside of the insets
protected boolean isAfter(int x, int y, Rectangle innerAlloc)
isAfter in class CompositeViewx - the X coordinate>= 0y - the Y coordinate>= 0innerAlloc - the allocated region; this is the area
inside of the insets
protected View getViewAtPoint(int x, int y, Rectangle alloc)
getViewAtPoint in class CompositeViewx - the X coordinate>= 0y - the Y coordinate>= 0alloc - the parents inner allocation on entry, which should
be changed to the childs allocation on exit
protected void childAllocation(int index, Rectangle alloc)
childAllocation in class CompositeViewindex - the index of the child view to
allocate,>= 0 && < getViewCount()alloc - the allocated regionprotected void layout(int width, int height)
width - the width (inside of the insets)>= 0height - the height (inside of the insets)>= 0public int getWidth()
public int getHeight()
protected void layoutMajorAxis(int targetSpan, int axis, int[] offsets, int[] spans)
targetSpan - the total span given to the view, which
would be used to layout the childrenaxis - the axis being layed outoffsets - the offsets from the origin of the view for
each of the child views; this is a return value and is
filled in by the implementation of this methodspans - the span of each child view; this is a return
value and is filled in by the implementation of this method
protected void layoutMinorAxis(int targetSpan, int axis, int[] offsets, int[] spans)
targetSpan - the total span given to the view, which
would be used to layout the childrenaxis - the axis being layed outoffsets - the offsets from the origin of the view for
each of the child views; this is a return value and is
filled in by the implementation of this methodspans - the span of each child view; this is a return
value and is filled in by the implementation of this method
protected SizeRequirements calculateMajorAxisRequirements(int axis, SizeRequirements r)
axis - the axis being studiedr - the SizeRequirements object;
if null one will be created
SizeRequirements objectjavax.swing.SizeRequirementsprotected SizeRequirements calculateMinorAxisRequirements(int axis, SizeRequirements r)
axis.
axis - the axis being studiedr - the SizeRequirements object;
if null one will be created
SizeRequirements objectjavax.swing.SizeRequirementsvoid checkRequests(int axis)
axis - the axis being studiedprotected void baselineLayout(int targetSpan, int axis, int[] offsets, int[] spans)
BoxView given the targetSpan,
which is the width (or height) of the region we have to
work with.
targetSpan - the total span given to the view, which
would be used to layout the childrenaxis - the axis being studied, either
View.X_AXIS or View.Y_AXISoffsets - an empty array filled by this method with
values specifying the location of each child viewspans - an empty array filled by this method with
values specifying the extent of each child viewprotected SizeRequirements baselineRequirements(int axis, SizeRequirements r)
BoxView
by examining the size of each child view.
axis - the axis being studiedr - the SizeRequirements object;
if null one will be created
SizeRequirements objectprotected int getOffset(int axis, int childIndex)
axis - the axis being studiedchildIndex - the index of the requested child
protected int getSpan(int axis, int childIndex)
axis - the axis being studiedchildIndex - the index of the requested child
protected boolean flipEastAndWestAtEnds(int position, javax.swing.text.Position.Bias bias)
Views
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 Views are layed out in
descending order. Otherwise the method would return false
indicating the Views are layed out in ascending order.
If the receiver is laying its Views along the
Y_AXIS, this will will return the value from
invoking the same method on the View
responsible for rendering position and
bias. Otherwise this will return false.
flipEastAndWestAtEnds in class CompositeViewposition - position into the modelbias - either Position.Bias.Forward or
Position.Bias.Backward
Views surrounding the
View responding for rendering
position and bias
are layed out in descending order; otherwise false