Class FieldView

javax.swing.text.FieldView

All Implemented Interfaces:: SwingConstants, TabExpander

Direct Known Subclasses:: PasswordView

public class FieldView extends PlainView

Extends the multi-line plain text view to be suitable for a single-line editor view. If the view is allocated extra space, the field must adjust for it. If the hosting component is a JTextField, this view will manage the ranges of the associated BoundedRangeModel and will adjust the horizontal allocation to match the current visibility settings of the JTextField.

See Also:

Field Summary

Fields declared in class PlainView

metrics

Modifier and Type	Field	Description
`protected FontMetrics`	`metrics`	Font metrics for the current font.

Fields declared in class View

BadBreakWeight, ExcellentBreakWeight, ForcedBreakWeight, GoodBreakWeight, X_AXIS, Y_AXIS

Modifier and Type	Field	Description
`static final int`	`BadBreakWeight`	The weight to indicate a view is a bad break opportunity for the purpose of formatting.
`static final int`	`ExcellentBreakWeight`	The weight to indicate a view supports breaking, and this represents a very attractive place to break.
`static final int`	`ForcedBreakWeight`	The weight to indicate a view supports breaking, and must be broken to be represented properly when placed in a view that formats its children by breaking them.
`static final int`	`GoodBreakWeight`	The weight to indicate a view supports breaking, but better opportunities probably exist.
`static final int`	`X_AXIS`	Axis for format/break operations.
`static final int`	`Y_AXIS`	Axis for format/break operations.

Fields declared in interface SwingConstants

BOTTOM, CENTER, EAST, HORIZONTAL, LEADING, LEFT, NEXT, NORTH, NORTH_EAST, NORTH_WEST, PREVIOUS, RIGHT, SOUTH, SOUTH_EAST, SOUTH_WEST, TOP, TRAILING, VERTICAL, WEST

Modifier and Type	Field	Description
`static final int`	`BOTTOM`	Box-orientation constant used to specify the bottom of a box.
`static final int`	`CENTER`	The central position in an area.
`static final int`	`EAST`	Compass-direction east (right).
`static final int`	`HORIZONTAL`	Horizontal orientation.
`static final int`	`LEADING`	Identifies the leading edge of text for use with left-to-right and right-to-left languages.
`static final int`	`LEFT`	Box-orientation constant used to specify the left side of a box.
`static final int`	`NEXT`	Identifies the next direction in a sequence.
`static final int`	`NORTH`	Compass-direction North (up).
`static final int`	`NORTH_EAST`	Compass-direction north-east (upper right).
`static final int`	`NORTH_WEST`	Compass-direction north west (upper left).
`static final int`	`PREVIOUS`	Identifies the previous direction in a sequence.
`static final int`	`RIGHT`	Box-orientation constant used to specify the right side of a box.
`static final int`	`SOUTH`	Compass-direction south (down).
`static final int`	`SOUTH_EAST`	Compass-direction south-east (lower right).
`static final int`	`SOUTH_WEST`	Compass-direction south-west (lower left).
`static final int`	`TOP`	Box-orientation constant used to specify the top of a box.
`static final int`	`TRAILING`	Identifies the trailing edge of text for use with left-to-right and right-to-left languages.
`static final int`	`VERTICAL`	Vertical orientation.
`static final int`	`WEST`	Compass-direction west (left).

Constructor Summary

Constructor	Description
`FieldView(Element elem)`	Constructs a new FieldView wrapped on an element.

Method Summary

Modifier and Type	Method	Description
`protected Shape`	`adjustAllocation(Shape a)`	Adjusts the allocation given to the view to be a suitable allocation for a text field.
`protected FontMetrics`	`getFontMetrics()`	Fetches the font metrics associated with the component hosting this view.
`float`	`getPreferredSpan(int axis)`	Determines the preferred span for this view along an axis.
`int`	`getResizeWeight(int axis)`	Determines the resizability of the view along the given axis.
`void`	`insertUpdate(DocumentEvent changes, Shape a, ViewFactory f)`	Gives notification that something was inserted into the document in a location that this view is responsible for.
`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 a)`	Renders using the given rendering surface and area on that surface.
`void`	`removeUpdate(DocumentEvent changes, Shape a, ViewFactory f)`	Gives notification that something was removed from the document in a location that this view is responsible for.
`int`	`viewToModel(float fx, float fy, 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 PlainView

changedUpdate, damageLineRange, drawLine, drawLine, drawSelectedText, drawSelectedText, drawUnselectedText, drawUnselectedText, getLineBuffer, getTabSize, lineToRect, nextTabStop, setSize, updateDamage, updateMetrics

Modifier and Type	Method	Description
`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.
`protected void`	`damageLineRange(int line0, int line1, Shape a, Component host)`	Repaint the given line range.
`protected void`	`drawLine(int lineIndex, Graphics2D g, float x, float y)`	Renders a line of text, suppressing whitespace at the end and expanding any tabs.
`protected void`	`drawLine(int lineIndex, Graphics g, int x, int y)`	Deprecated. replaced by `PlainView.drawLine(int, Graphics2D, float, float)`
`protected float`	`drawSelectedText(Graphics2D g, float x, float y, int p0, int p1)`	Renders the given range in the model as selected text.
`protected int`	`drawSelectedText(Graphics g, int x, int y, int p0, int p1)`	Deprecated. replaced by `PlainView.drawSelectedText(Graphics2D, float, float, int, int)`
`protected float`	`drawUnselectedText(Graphics2D g, float x, float y, int p0, int p1)`	Renders the given range in the model as normal unselected text.
`protected int`	`drawUnselectedText(Graphics g, int x, int y, int p0, int p1)`	Deprecated. replaced by `PlainView.drawUnselectedText(Graphics2D, float, float, int, int)`
`protected final Segment`	`getLineBuffer()`	Gives access to a buffer that can be used to fetch text from the associated document.
`protected int`	`getTabSize()`	Returns the tab size set for the document, defaulting to 8.
`protected Rectangle`	`lineToRect(Shape a, int line)`	Determine the rectangle that represents the given line.
`float`	`nextTabStop(float x, int tabOffset)`	Returns the next tab stop position after a given reference position.
`void`	`setSize(float width, float height)`	Sets the size of the view.
`protected void`	`updateDamage(DocumentEvent changes, Shape a, ViewFactory f)`	Repaint the region of change covered by the given document event.
`protected void`	`updateMetrics()`	Checks to see if the font metrics and longest line are up-to-date.

Methods declared in class View

append, breakView, createFragment, forwardUpdate, forwardUpdateToView, getAlignment, getAttributes, getBreakWeight, getChildAllocation, getContainer, getDocument, getElement, getEndOffset, getGraphics, getMaximumSpan, getMinimumSpan, getNextVisualPositionFrom, getParent, getStartOffset, getToolTipText, getView, getViewCount, getViewFactory, getViewIndex, getViewIndex, insert, isVisible, modelToView, modelToView, preferenceChanged, remove, removeAll, replace, setParent, updateChildren, updateLayout, viewToModel

Modifier and Type	Method	Description
`void`	`append(View v)`	Appends a single child view.
`View`	`breakView(int axis, int offset, float pos, float len)`	Tries to break this view on the given axis.
`View`	`createFragment(int p0, int p1)`	Creates a view that represents a portion of the element.
`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.
`protected void`	`forwardUpdateToView(View v, DocumentEvent e, Shape a, ViewFactory f)`	Forwards the `DocumentEvent` to the give child view.
`float`	`getAlignment(int axis)`	Determines the desired alignment for this view along an axis.
`AttributeSet`	`getAttributes()`	Fetches the attributes to use when rendering.
`int`	`getBreakWeight(int axis, float pos, float len)`	Determines how attractive a break opportunity in this view is.
`Shape`	`getChildAllocation(int index, Shape a)`	Fetches the allocation for the given child view.
`Container`	`getContainer()`	Fetches the container hosting the view.
`Document`	`getDocument()`	Fetches the model associated with the view.
`Element`	`getElement()`	Fetches the structural portion of the subject that this view is mapped to.
`int`	`getEndOffset()`	Fetches the portion of the model for which this view is responsible.
`Graphics`	`getGraphics()`	Fetch a `Graphics` for rendering.
`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`	`getNextVisualPositionFrom(int pos, Position.Bias b, Shape a, int direction, Position.Bias[] biasRet)`	Provides a way to determine the next visually represented model location at which one might place a caret.
`View`	`getParent()`	Returns the parent of the view.
`int`	`getStartOffset()`	Fetches the portion of the model for which this view is responsible.
`String`	`getToolTipText(float x, float y, Shape allocation)`	Returns the tooltip text at the specified location.
`View`	`getView(int n)`	Gets the nth child view.
`int`	`getViewCount()`	Returns the number of views in this view.
`ViewFactory`	`getViewFactory()`	Fetches the `ViewFactory` implementation that is feeding the view hierarchy.
`int`	`getViewIndex(float x, float y, Shape allocation)`	Returns the child view index representing the given position in the view.
`int`	`getViewIndex(int pos, Position.Bias b)`	Returns the child view index representing the given position in the model.
`void`	`insert(int offs, View v)`	Inserts a single child view.
`boolean`	`isVisible()`	Returns a boolean that indicates whether the view is visible or not.
`Shape`	`modelToView(int pos, Shape a)`	Deprecated.
`Shape`	`modelToView(int p0, Position.Bias b0, int p1, Position.Bias b1, Shape a)`	Provides a mapping, for a given region, from the document model coordinate space to the view coordinate space.
`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`	`remove(int i)`	Removes one of the children at the given position.
`void`	`removeAll()`	Removes all of the children.
`void`	`replace(int offset, int length, View[] views)`	Replaces child views.
`void`	`setParent(View parent)`	Establishes the parent view for this view.
`protected boolean`	`updateChildren(DocumentEvent.ElementChange ec, DocumentEvent e, ViewFactory f)`	Updates the child views in response to receiving notification that the model changed, and there is change record for the element this view is responsible for.
`protected void`	`updateLayout(DocumentEvent.ElementChange ec, DocumentEvent e, Shape a)`	Updates the layout in response to receiving notification of change from the model.
`int`	`viewToModel(float x, float y, Shape a)`	Deprecated.

Methods declared in class Object

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

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this object.
`final void`	`notify()`	Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()`	Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()`	Returns a string representation of the object.
`final void`	`wait()`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Constructor Details

FieldView

public FieldView(Element elem)

Constructs a new FieldView wrapped on an element.

Parameters:: elem - the element

Method Details

getFontMetrics

protected FontMetrics getFontMetrics()

Fetches the font metrics associated with the component hosting this view.

Returns:: the metrics

adjustAllocation

protected Shape adjustAllocation(Shape a)

Adjusts the allocation given to the view to be a suitable allocation for a text field. If the view has been allocated more than the preferred span vertically, the allocation is changed to be centered vertically. Horizontally the view is adjusted according to the horizontal alignment property set on the associated JTextField (if that is the type of the hosting component).

Parameters:: a - the allocation given to the view, which may need to be adjusted.
Returns:: the allocation that the superclass should use.

paint

public void paint(Graphics g, Shape a)

Renders using the given rendering surface and area on that surface. The view may need to do layout and create child views to enable itself to render into the given allocation.

Overrides:

paint in class PlainView

Parameters:

g - the rendering surface to use

a - the allocated region to render into

See Also:

getPreferredSpan

public float getPreferredSpan(int axis)

Determines the preferred span for this view along an axis.

Overrides:: getPreferredSpan in class PlainView
Parameters:: axis - may be either View.X_AXIS or View.Y_AXIS
Returns:: the span the view would like to be rendered into >= 0. 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.

getResizeWeight

public int getResizeWeight(int axis)

Determines the resizability of the view along the given axis. A value of 0 or less is not resizable.

Overrides:: getResizeWeight in class View
Parameters:: axis - View.X_AXIS or View.Y_AXIS
Returns:: the weight -> 1 for View.X_AXIS, else 0

modelToView

public Shape modelToView(int pos, Shape a, Position.Bias b) throws BadLocationException

Provides a mapping from the document model coordinate space to the coordinate space of the view mapped to it.

Overrides:

modelToView in class PlainView

Parameters:

pos - the position to convert >= 0

a - the allocated region to render into

b - the bias toward the previous character or the next character represented by the offset, in case the position is a boundary of two views; b will have one of these values:

Position.Bias.Forward
Position.Bias.Backward

Returns:

the bounding box of the given position

Throws:

BadLocationException - if the given position does not represent a valid location in the associated document

See Also:

viewToModel

public int viewToModel(float fx, float fy, Shape a, Position.Bias[] bias)

Provides a mapping from the view coordinate space to the logical coordinate space of the model.

Overrides:

viewToModel in class PlainView

Parameters:

fx - the X coordinate >= 0.0f

fy - the Y coordinate >= 0.0f

a - the allocated region to render into

bias - the returned bias

Returns:

the location within the model that best represents the given point in the view

See Also:

insertUpdate

public void insertUpdate(DocumentEvent changes, Shape a, ViewFactory f)

Gives notification that something was inserted into the document in a location that this view is responsible for.

Overrides:

insertUpdate in class PlainView

Parameters:

changes - 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:

removeUpdate

public void removeUpdate(DocumentEvent changes, Shape a, ViewFactory f)

Gives notification that something was removed from the document in a location that this view is responsible for.

Overrides:

removeUpdate in class PlainView

Parameters:

changes - 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:

© 1993, 2025, 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.