java.lang.Object
- javax.swing.text.View
- - javax.swing.text.AsyncBoxView

All Implemented Interfaces:

SwingConstants
```
public class AsyncBoxView
extends View
```
A box that does layout asynchronously. This is useful to keep the GUI event thread moving by not doing any layout on it. The layout is done on a granularity of operations on the child views. After each child view is accessed for some part of layout (a potentially time consuming operation) the remaining tasks can be abandoned or a new higher priority task (i.e. to service a synchronous request or a visible area) can be taken on.
While the child view is being accessed a read lock is acquired on the associated document so that the model is stable while being accessed.

Since:

1.3

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`class`	`AsyncBoxView.ChildLocator`	A class to manage the effective position of the child views in a localized area while changes are being made around the localized area.
`class`	`AsyncBoxView.ChildState`	A record representing the layout state of a child view.

Field Summary

Fields
Modifier and Type Field Description

protected AsyncBoxView.ChildLocator locator
Object that manages the offsets of the children.
- 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

AsyncBoxView(Element elem, int axis)
Construct a box view that does asynchronous layout.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`protected AsyncBoxView.ChildState`	`createChildState(View v)`	New ChildState records are created through this method to allow subclasses the extend the ChildState records to do/hold more.
`protected void`	`flushRequirementChanges()`	Publish the changes in preferences upward to the parent view.
`float`	`getBottomInset()`	Get the bottom part of the margin around the view.
`Shape`	`getChildAllocation(int index, Shape a)`	Fetches the allocation for the given child view.
`protected AsyncBoxView.ChildState`	`getChildState(int index)`	Fetch the object representing the layout state of of the child at the given index.
`protected boolean`	`getEstimatedMajorSpan()`	Is the major span currently estimated?
`protected float`	`getInsetSpan(int axis)`	Fetch the span along an axis that is taken up by the insets.
`protected LayoutQueue`	`getLayoutQueue()`	Fetch the queue to use for layout.
`float`	`getLeftInset()`	Get the left part of the margin around the view.
`int`	`getMajorAxis()`	Fetch the major axis (the axis the children are tiled along).
`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.
`int`	`getMinorAxis()`	Fetch the minor axis (the axis orthogonal to the tiled axis).
`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 that one might place a caret.
`float`	`getPreferredSpan(int axis)`	Determines the preferred span for this view along an axis.
`float`	`getRightInset()`	Get the right part of the margin around the view.
`float`	`getTopInset()`	Get the top part of the margin around the view.
`View`	`getView(int n)`	Gets the nth child view.
`int`	`getViewCount()`	Returns the number of views in this view.
`int`	`getViewIndex(int pos, Position.Bias b)`	Returns the child view index representing the given position in the model.
`protected int`	`getViewIndexAtPosition(int pos, Position.Bias b)`	Fetches the child view index representing the given position in the model.
`protected void`	`loadChildren(ViewFactory f)`	Loads all of the children to initialize the view.
`protected void`	`majorRequirementChange(AsyncBoxView.ChildState cs, float delta)`	Requirements changed along the major axis.
`protected void`	`minorRequirementChange(AsyncBoxView.ChildState cs)`	Requirements changed along the minor axis.
`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 alloc)`	Render the view using the given allocation and rendering surface.
`void`	`preferenceChanged(View child, boolean width, boolean height)`	Child views can call this on the parent to indicate that the preference has changed and should be reconsidered for layout.
`void`	`replace(int offset, int length, View[] views)`	Calls the superclass to update the child views, and updates the status records for the children.
`void`	`setBottomInset(float i)`	Set the bottom part of the margin around the view.
`protected void`	`setEstimatedMajorSpan(boolean isEstimated)`	Set the estimatedMajorSpan property that determines if the major span should be treated as being estimated.
`void`	`setLeftInset(float i)`	Set the left part of the margin around the view.
`void`	`setParent(View parent)`	Sets the parent of the view.
`void`	`setRightInset(float i)`	Set the right part of the margin around the view.
`void`	`setSize(float width, float height)`	Sets the size of the view.
`void`	`setTopInset(float i)`	Set the top part of the margin around the view.
`protected void`	`updateLayout(DocumentEvent.ElementChange ec, DocumentEvent e, Shape a)`	Update the layout in response to receiving notification of change from the model.
`int`	`viewToModel(float x, float y, Shape a, Position.Bias[] biasReturn)`	Provides a mapping from the view coordinate space to the logical coordinate space of the model.

Methods declared in class javax.swing.text.View
append, breakView, changedUpdate, createFragment, forwardUpdate, forwardUpdateToView, getAlignment, getAttributes, getBreakWeight, getContainer, getDocument, getElement, getEndOffset, getGraphics, getParent, getResizeWeight, getStartOffset, getToolTipText, getViewFactory, getViewIndex, insert, insertUpdate, isVisible, modelToView, modelToView, remove, removeAll, removeUpdate, updateChildren, viewToModel

Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - locator
```
protected AsyncBoxView.ChildLocator locator
```
    Object that manages the offsets of the children. All locking for management of child locations is on this object.
- Constructor Detail
  - AsyncBoxView
```
public AsyncBoxView(Element elem,
                    int axis)
```
    Construct a box view that does asynchronous layout.
    
    Parameters:
    
    elem - the element of the model to represent
    
    axis - the axis to tile along. This can be either X_AXIS or Y_AXIS.
- Method Detail
  - getMajorAxis
```
public int getMajorAxis()
```
    Fetch the major axis (the axis the children are tiled along). This will have a value of either X_AXIS or Y_AXIS.
    
    Returns:
    
    the major axis
  - getMinorAxis
```
public int getMinorAxis()
```
    Fetch the minor axis (the axis orthogonal to the tiled axis). This will have a value of either X_AXIS or Y_AXIS.
    
    Returns:
    
    the minor axis
  - getTopInset
```
public float getTopInset()
```
    Get the top part of the margin around the view.
    
    Returns:
    
    the top part of the margin around the view
  - setTopInset
```
public void setTopInset(float i)
```
    Set the top part of the margin around the view.
    
    Parameters:
    
    i - the value of the inset
  - getBottomInset
```
public float getBottomInset()
```
    Get the bottom part of the margin around the view.
    
    Returns:
    
    the bottom part of the margin around the view
  - setBottomInset
```
public void setBottomInset(float i)
```
    Set the bottom part of the margin around the view.
    
    Parameters:
    
    i - the value of the inset
  - getLeftInset
```
public float getLeftInset()
```
    Get the left part of the margin around the view.
    
    Returns:
    
    the left part of the margin around the view
  - setLeftInset
```
public void setLeftInset(float i)
```
    Set the left part of the margin around the view.
    
    Parameters:
    
    i - the value of the inset
  - getRightInset
```
public float getRightInset()
```
    Get the right part of the margin around the view.
    
    Returns:
    
    the right part of the margin around the view
  - setRightInset
```
public void setRightInset(float i)
```
    Set the right part of the margin around the view.
    
    Parameters:
    
    i - the value of the inset
  - getInsetSpan
```
protected float getInsetSpan(int axis)
```
    Fetch the span along an axis that is taken up by the insets.
    
    Parameters:
    
    axis - the axis to determine the total insets along, either X_AXIS or Y_AXIS.
    
    Returns:
    
    the span along an axis that is taken up by the insets
    
    Since:
    
    1.4
  - setEstimatedMajorSpan
```
protected void setEstimatedMajorSpan(boolean isEstimated)
```
    Set the estimatedMajorSpan property that determines if the major span should be treated as being estimated. If this property is true, the value of setSize along the major axis will change the requirements along the major axis and incremental changes will be ignored until all of the children have been updated (which will cause the property to automatically be set to false). If the property is false the value of the majorSpan will be considered to be accurate and incremental changes will be added into the total as they are calculated.
    
    Parameters:
    
    isEstimated - new value for the estimatedMajorSpan property
    
    Since:
    
    1.4
  - getEstimatedMajorSpan
```
protected boolean getEstimatedMajorSpan()
```
    Is the major span currently estimated?
    
    Returns:
    
    whether or not the major span currently estimated
    
    Since:
    
    1.4
  - getChildState
```
protected AsyncBoxView.ChildState getChildState(int index)
```
    Fetch the object representing the layout state of of the child at the given index.
    
    Parameters:
    
    index - the child index. This should be a value >= 0 and < getViewCount().
    
    Returns:
    
    the object representing the layout state of of the child at the given index
  - getLayoutQueue
```
protected LayoutQueue getLayoutQueue()
```
    Fetch the queue to use for layout.
    
    Returns:
    
    the queue to use for layout
  - createChildState
```
protected AsyncBoxView.ChildState createChildState(View v)
```
    New ChildState records are created through this method to allow subclasses the extend the ChildState records to do/hold more.
    
    Parameters:
    
    v - the view
    
    Returns:
    
    new child state
  - majorRequirementChange
```
protected void majorRequirementChange(AsyncBoxView.ChildState cs,
                                      float delta)
```
    Requirements changed along the major axis. This is called by the thread doing layout for the given ChildState object when it has completed fetching the child views new preferences. Typically this would be the layout thread, but might be the event thread if it is trying to update something immediately (such as to perform a model/view translation).
    This is implemented to mark the major axis as having changed so that a future check to see if the requirements need to be published to the parent view will consider the major axis. If the span along the major axis is not estimated, it is updated by the given delta to reflect the incremental change. The delta is ignored if the major span is estimated.
    
    Parameters:
    
    cs - the child state
    
    delta - the delta
  - minorRequirementChange
```
protected void minorRequirementChange(AsyncBoxView.ChildState cs)
```
    Requirements changed along the minor axis. This is called by the thread doing layout for the given ChildState object when it has completed fetching the child views new preferences. Typically this would be the layout thread, but might be the GUI thread if it is trying to update something immediately (such as to perform a model/view translation).
    
    Parameters:
    
    cs - the child state
  - flushRequirementChanges
```
protected void flushRequirementChanges()
```
    Publish the changes in preferences upward to the parent view. This is normally called by the layout thread.
  - replace
```
public void replace(int offset,
                    int length,
                    
```

Class AsyncBoxView

Nested Class Summary

Field Summary

Fields declared in class javax.swing.text.View

Fields declared in interface javax.swing.SwingConstants

Constructor Summary

Method Summary

Methods declared in class javax.swing.text.View

Methods declared in class java.lang.Object

Field Detail

locator

Constructor Detail

AsyncBoxView

Method Detail

getMajorAxis

getMinorAxis

getTopInset

setTopInset

getBottomInset

setBottomInset

getLeftInset

setLeftInset

getRightInset

setRightInset

getInsetSpan

setEstimatedMajorSpan

getEstimatedMajorSpan

getChildState

getLayoutQueue

createChildState

majorRequirementChange

minorRequirementChange

flushRequirementChanges

replace