Class DirectionalTextHelper

java.lang.Object
com.google.gwt.user.client.ui.DirectionalTextHelper
All Implemented Interfaces:
HasDirectionEstimator

public class DirectionalTextHelper extends 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.
  • Field Details

    • DEFAULT_DIRECTION_ESTIMATOR

      public static final DirectionEstimator DEFAULT_DIRECTION_ESTIMATOR
      A default direction estimator instance.
  • Constructor Details

    • DirectionalTextHelper

      public DirectionalTextHelper(Element element, boolean isElementInline)
      Parameters:
      element - The widget's element holding text.
      isElementInline - Whether the element is an inline element.
  • Method Details

    • getDirectionEstimator

      public DirectionEstimator getDirectionEstimator()
      Description copied from interface: HasDirectionEstimator
      Returns the DirectionEstimator object.
      Specified by:
      getDirectionEstimator in interface HasDirectionEstimator
    • getTextDirection

      public HasDirection.Direction getTextDirection()
    • getText

      public String getText()
      Get the inner text of the element, taking the inner span wrap into consideration, if needed.
      Returns:
      the text
    • getHtml

      public String getHtml()
      Get the inner html of the element, taking the inner span wrap into consideration, if needed.
      Returns:
      the html
    • getTextOrHtml

      public String getTextOrHtml(boolean isHtml)
      Get the inner text or html of the element, taking the inner span wrap into consideration, if needed. Prefer using getText() or getHtml() instead of this method.
      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)
      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.
    • setText

      public void setText(String content)
      Sets the element's content to the given value (plain text). If direction estimation is off, the direction is verified to match the element's initial direction. Otherwise, the direction is affected as described at setText(String, Direction).
      Parameters:
      content - the element's new content
    • setHtml

      public void setHtml(SafeHtml content)
      Sets the element's content to the given value (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 setHtml(String, Direction).
      Parameters:
      content - the element's new content
    • setHtml

      public void setHtml(String content)
      Sets the element's content to the given value (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 setHtml(String, Direction).
      Parameters:
      content - the element's new content
    • setTextOrHtml

      public void setTextOrHtml(String content, boolean isHtml)
      Sets the element's content to the given value (either plain text or HTML). Prefer using setText or setHtml instead of this method.
      Parameters:
      content - the element's new content
      isHtml - whether the content is HTML
    • setText

      public void setText(String content, HasDirection.Direction dir)
      Sets the element's content to the given value (plain text), 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
    • setHtml

      public void setHtml(SafeHtml content, HasDirection.Direction dir)
      Sets the element's content to the given value (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
    • setHtml

      public void setHtml(String content, HasDirection.Direction dir)
      Sets the element's content to the given value (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
    • setTextOrHtml

      public void setTextOrHtml(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. Prefer using setText or setHtml instead of this method.
      Parameters:
      content - the element's new content
      dir - the content's direction
      isHtml - whether the content is HTML