Class BoxView

java.lang.Object

javax.swing.text.View

javax.swing.text.CompositeView

javax.swing.text.BoxView

All Implemented Interfaces:

SwingConstants

Direct Known Subclasses:

BlockView, FlowView, TableView, TableView.TableCell, TableView.TableRow, WrappedPlainView, ZoneView

public class BoxView
extends CompositeView

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 orthogonal 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.

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
BoxView(Element elem, int axis)	Constructs a BoxView.

Method Summary

Modifier and Type	Method	Description
protected void	baselineLayout(int targetSpan, int axis, int[] offsets, int[] spans)	Computes the location and extent of each child view in this 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)	Calculates the size requirements for this BoxView by examining the size of each child view.
protected SizeRequirements	calculateMajorAxisRequirements(int axis, SizeRequirements r)	Calculates the size requirements for the major axis axis.
protected SizeRequirements	calculateMinorAxisRequirements(int axis, SizeRequirements r)	Calculates the size requirements for the minor axis axis.
protected void	childAllocation(int index, Rectangle alloc)	Allocates a region for a child view.
protected boolean	flipEastAndWestAtEnds(int position, Position.Bias bias)	Determines in which direction the next view lays.
protected void	forwardUpdate(DocumentEvent.ElementChange ec, DocumentEvent e, Shape a, ViewFactory f)	Forwards the given DocumentEvent to the child views that need to be notified of the change to the model.
float	getAlignment(int axis)	Determines the desired alignment for this view along an axis.
int	getAxis()	Fetches the tile axis property.
Shape	getChildAllocation(int index, Shape a)	Fetches the allocation for the given child view.
int	getHeight()	Returns the current height of the box.
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.
protected int	getOffset(int axis, int childIndex)	Fetches the offset of a particular child's current layout.
float	getPreferredSpan(int axis)	Determines the preferred span for this view along an axis.
int	getResizeWeight(int axis)	Gets the resize weight.
protected int	getSpan(int axis, int childIndex)	Fetches the span of a particular child's current layout.
protected View	getViewAtPoint(int x, int y, Rectangle alloc)	Fetches the child view at the given coordinates.
int	getWidth()	Returns the current width of the box.
protected boolean	isAfter(int x, int y, Rectangle innerAlloc)	Determines if a point falls after an allocated region.
protected boolean	isAllocationValid()	Are the allocations for the children still valid?
protected boolean	isBefore(int x, int y, Rectangle innerAlloc)	Determines if a point falls before an allocated region.
protected boolean	isLayoutValid(int axis)	Determines if the layout is valid along the given axis.
protected void	layout(int width, int height)	Perform layout on the box
void	layoutChanged(int axis)	Invalidates the layout along an axis.
protected void	layoutMajorAxis(int targetSpan, int axis, int[] offsets, int[] spans)	Performs layout for the major axis of the box (i.e. the axis that it represents).
protected void	layoutMinorAxis(int targetSpan, int axis, int[] offsets, int[] spans)	Performs layout for the minor axis of the box (i.e. the axis orthogonal to the axis that it represents).
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 allocation)	Renders the BoxView using the given rendering surface and area on that surface.
protected void	paintChild(Graphics g, Rectangle alloc, int index)	Paints a child.
void	preferenceChanged(View child, boolean width, boolean height)	This is called by a child to indicate its preferred span has changed.
void	replace(int index, int length, View[] elems)	Invalidates the layout and resizes the cache of requests/allocations.
void	setAxis(int axis)	Sets the tile axis property.
void	setSize(float width, float height)	Sets the size of the view.
int	viewToModel(float x, float y, Shape a, Position.Bias[] bias)	Provides a mapping from the view coordinate space to the logical coordinate space of the model.

Methods declared in class javax.swing.text.CompositeView

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

Methods declared in class javax.swing.text.View

append, breakView, changedUpdate, createFragment, forwardUpdateToView, getAttributes, getBreakWeight, getContainer,