How to use

removeClassName

method

in

com.google.gwt.user.client.Element

/**
 * Removes any previous emphasis made by drag&drag
 */
protected void deEmphasis() {
  if (currentEmphasis != null) {
    currentEmphasis.removeClassName(OVER);
    currentEmphasis.removeClassName(OVER_SPLITTER);
    currentEmphasis = null;
  }
}

public void openExpander() {
  element.removeClassName("hover");
  element.removeClassName("closed");
  element.addClassName("open");
  opened = true;
  updateColors();
}

  @Override
  public void onMouseOut(MouseOutEvent event) {
    getElement().removeClassName("hover");
    updateColors();
  }
}, MouseOutEvent.getType());

public void closeExpander() {
  element.removeClassName("hover");
  element.removeClassName("open");
  element.addClassName("closed");
  opened = false;
  updateColors();
}

public void updateSingleTabStyle() {
  if (tabLabels.size() <= 1) {
    tabContainer.addClassName(SINGLE_TAB_CLASS_NAME);
  } else {
    tabContainer.removeClassName(SINGLE_TAB_CLASS_NAME);
  }
}

  @Override
  public void onTouchStart(TouchStartEvent event) {
    getElement().removeClassName("hover");
    setColorsClick();
  }
});

/**
 * Set the state: not active, not clicked.
 */
private void setColorsOff() {
  getElement().removeClassName("active");
}

  @Override
  public void onTouchStart(TouchStartEvent event) {
    getElement().removeClassName("hover");
    setColorsClick();
    event.preventDefault();
  }
});

  @Override
  public void onMouseOut(MouseOutEvent event) {
    getElement().removeClassName("hover");
    updateColors();
  }
}, MouseOutEvent.getType());

 @Override
 public void invokeBinding(final Element element, final Annotation annotation) {
  final User user = userCache.getUser();
  final Set<Role> extractedRoles = roleExtractor.extractAllRoles((RestrictedAccess) annotation);
  if (User.ANONYMOUS.equals(user) || !user.getRoles().containsAll(extractedRoles)) {
   element.addClassName(RestrictedAccess.CSS_CLASS_NAME);
  }
  else {
   element.removeClassName(RestrictedAccess.CSS_CLASS_NAME);
  }
 }
});

 @Override
 public void invokeBinding(final Element element, final Annotation annotation) {
  final User user = userCache.getUser();
  final Set<Role> extractedRoles = roleExtractor.extractAllRoles((RestrictedAccess) annotation);
  if (User.ANONYMOUS.equals(user) || !user.getRoles().containsAll(extractedRoles)) {
   element.addClassName(RestrictedAccess.CSS_CLASS_NAME);
  }
  else {
   element.removeClassName(RestrictedAccess.CSS_CLASS_NAME);
  }
 }
});

  private void classNameToggle(final boolean value,
                 final String className) {
    if (value) {
      getElement().addClassName(className);
    } else {
      getElement().removeClassName(className);
    }
  }
}

  /**
   * @param iconName
   */
  public void setFixedWidth(boolean fixedWidth) {
    if (fixedWidth)
      getElement().addClassName("fa-fw"); //$NON-NLS-1$
    else
      getElement().removeClassName("fa-fw"); //$NON-NLS-1$
  }
}

  @Override
  public void onTouchEnd(TouchEndEvent event) {
    getElement().removeClassName("hover");
    groupBar.handleTileClick((VTemporaryAppTileGroup) group, that);
    updateColors();
    event.preventDefault();
  }
});

/**
 * Set the state: active, but not in a click or touch.
 */
private void setColorsOn() {
  getElement().removeClassName("clicked");
  getElement().addClassName("active");
}

@Override
public void setText(String value) {
  valueBuilder = maskValue(value);
  String text = valueBuilder.toString();
  if (text.equals(nullRepresentation) || valueBuilder.length() == 0) {
    getElement().addClassName(getEmptyFieldClass());
  } else {
    getElement().removeClassName(getEmptyFieldClass());
  }
  super.setText(text);
}

public void updateWaves(boolean enabled, UIObject obj) {
  if (obj instanceof MaterialWidget) {
    MaterialWidget widget = (MaterialWidget) obj;
    if (enabled) {
      if (widget.getWaves() != null) {
        widget.getElement().addClassName(CssName.WAVES_EFFECT);
      }
    } else {
      widget.getElement().removeClassName(CssName.WAVES_EFFECT);
    }
  }
}

public void updateWaves(boolean enabled, UIObject obj) {
  if (obj instanceof MaterialWidget) {
    MaterialWidget widget = (MaterialWidget) obj;
    if (enabled) {
      if (widget.getWaves() != null) {
        widget.getElement().addClassName(CssName.WAVES_EFFECT);
      }
    } else {
      widget.getElement().removeClassName(CssName.WAVES_EFFECT);
    }
  }
}

  @Override
  public void onTouchEnd(TouchEndEvent event) {
    getElement().removeClassName("hover");
    setActiveState(true);
    eventBus.fireEvent(new AppActivationEvent(appTile.getName()));
  }
});

@Override
protected void setColPriority(ComplexPanel col, String priority) {
  super.setColPriority(col, priority);
  if (col == null) return;
  if (priority != null && !priority.isEmpty()) {
    JQMCommon.setAttribute(col.getElement(), "data-priority", priority);
    col.getElement().removeClassName(JQM4GWT_COL_PERSISTENT);
  } else {
    JQMCommon.setAttribute(col.getElement(), "data-priority", null);
    col.getElement().addClassName(JQM4GWT_COL_PERSISTENT);
  }
}