com.google.gwt.user.client.ui
Class DirectionalTextHelper

java.lang.Object
  com.google.gwt.user.client.ui.DirectionalTextHelper

All Implemented Interfaces:

HasDirectionEstimator

public class DirectionalTextHelper
extends java.lang.Object
implements HasDirectionEstimator

A helper class for displaying bidi (i.e. potentially opposite-direction) text or HTML in an element. Note: this class assumes that callers perform all their text/html and direction manipulations through it alone.

DEFAULT_DIRECTION_ESTIMATOR

public static final DirectionEstimator DEFAULT_DIRECTION_ESTIMATOR

A default direction estimator instance.

DirectionalTextHelper

public DirectionalTextHelper(Element element,
                             boolean isElementInline)

Parameters:

element - The widget's element holding text.

isElementInline - Whether the element is an inline element.

getDirectionEstimator

public DirectionEstimator getDirectionEstimator()

Description copied from interface: HasDirectionEstimator

Returns the DirectionEstimator object.

Specified by:

getDirectionEstimator in interface HasDirectionEstimator

getTextDirection

public HasDirection.Direction getTextDirection()

getTextOrHtml

public java.lang.String getTextOrHtml(boolean isHtml)

Get the inner text or html of the element, taking the inner span wrap into consideration, if needed.

Parameters:

isHtml - true to get the inner html, false to get the inner text

Returns:

the text or html

setDirection

@Deprecated
public void setDirection(HasDirection.Direction direction)

Deprecated. 

Provides implementation for HasDirection's method setDirection (normally deprecated), dealing with backwards compatibility issues.

setDirectionEstimator

public void setDirectionEstimator(boolean enabled)

See note at setDirectionEstimator(com.google.gwt.i18n.shared.DirectionEstimator).

Specified by:

setDirectionEstimator in interface HasDirectionEstimator

Parameters:

enabled - Whether to enable direction estimation. If true, sets the DirectionEstimator object to a default DirectionEstimator.

setDirectionEstimator

public void setDirectionEstimator(DirectionEstimator directionEstimator)

Note: if the element already has non-empty content, this will update its direction according to the new estimator's result. This may cause flicker, and thus should be avoided; DirectionEstimator should be set before the element has any content.

Specified by:

setDirectionEstimator in interface HasDirectionEstimator

Parameters:

directionEstimator - The DirectionEstimator to be set. null means turning off direction estimation.

setTextOrHtml

public void setTextOrHtml(java.lang.String content,
                          boolean isHtml)

Sets the element's content to the given value (either plain text or HTML). If direction estimation is off, the direction is verified to match the element's initial direction. Otherwise, the direction is affected as described at setTextOrHtml(String, Direction, boolean).

Parameters:

content - the element's new content

isHtml - whether the content is HTML

setTextOrHtml

public void setTextOrHtml(java.lang.String content,
                          HasDirection.Direction dir,
                          boolean isHtml)

Sets the element's content to the given value (either plain text or HTML), applying the given direction.

Implementation details:

• If the element is a block element, sets its dir attribute according to the given direction.
• Otherwise (i.e. the element is inline), the direction is set using a nested <span dir=...> element which holds the content of the element. This nested span may be followed by a zero-width Unicode direction character (LRM or RLM). This manipulation is necessary to prevent garbling in case the direction of the element is opposite to the direction of its context. See BidiFormatter for more details.

Parameters:

content - the element's new content

dir - the content's direction

isHtml - whether the content is HTML