How to use

getAbsoluteRight

method

in

com.google.gwt.user.client.Element

 public static boolean isVisible(Element e)
{
  //vp = viewPort, b = bottom, l = left, t = top, r = right
  int vpWidth   = Window.getClientWidth();
  int vpHeight = Window.getClientHeight();


  boolean tViz = ( e.getAbsoluteTop() >= 0 && e.getAbsoluteTop()<  vpHeight);
  boolean bViz = (e.getAbsoluteBottom() >  0 && e.getAbsoluteBottom() <= vpHeight);
  boolean lViz = (e.getAbsoluteLeft() >= 0 && e.getAbsoluteLeft() < vpWidth);
  boolean rViz = (e.getAbsoluteRight()  >  0 && e.getAbsoluteRight()  <= vpWidth);

  boolean vVisible   = tViz && bViz;
  boolean hVisible   = lViz && rViz;

  return hVisible && vVisible;
}

void resize()
{
  if( fakeDiv == null )
  {
    fakeDiv = DOM.createDiv();
    fakeDiv.getStyle().setPosition( Position.FIXED );
    fakeDiv.getStyle().setLeft( -10000, Unit.PX );
    getElement().getParentElement().insertAfter( fakeDiv, getElement() );
    applyStyle( fakeDiv );
  }
  int width = getElement().getAbsoluteRight() - getElement().getAbsoluteLeft();
  fakeDiv.getStyle().setWidth( width - 10 - 2, Unit.PX );
  fakeDiv.setInnerText( getText() );
  int height = getElement().getClientHeight();
  int newHeight = fakeDiv.getClientHeight() + 25;
  if( height < newHeight )
    getElement().getStyle().setHeight( newHeight, Unit.PX );
}

void resize()
{
  if( fakeDiv == null )
  {
    fakeDiv = DOM.createDiv();
    fakeDiv.getStyle().setPosition( Position.FIXED );
    fakeDiv.getStyle().setLeft( -10000, Unit.PX );
    getElement().getParentElement().insertAfter( fakeDiv, getElement() );
    applyStyle( fakeDiv );
  }
  int width = getElement().getAbsoluteRight() - getElement().getAbsoluteLeft();
  fakeDiv.getStyle().setWidth( width - 10 - 2, Unit.PX );
  fakeDiv.setInnerText( getText() );
  int height = getElement().getClientHeight();
  int newHeight = fakeDiv.getClientHeight() + 25;
  if( height < newHeight )
    getElement().getStyle().setHeight( newHeight, Unit.PX );
}

private void attachAutoCloseHandler() {
  removeAutoCloseHandler();
  autoCloseHandler = RootPanel.get().addDomHandler(e -> {
    if (isVisible()) {
      int top = content.asWidget().getElement().getAbsoluteTop();
      int left = content.asWidget().getElement().getAbsoluteLeft();
      int right = content.asWidget().getElement().getAbsoluteRight();
      int bottom = content.asWidget().getElement().getAbsoluteBottom();
      if (e.getY() < top || e.getY() > bottom || e.getX() < left || e.getX() > right) {
        hide();
      }
    }
  }, ClickEvent.getType());
}

private void show(final DragContext context) {
  //Get centre of DropTarget
  final Widget dropTargetParent = context.dropController.getDropTarget();
  int cxmin = dropTargetParent.getElement().getAbsoluteLeft();
  int cymin = dropTargetParent.getElement().getAbsoluteTop();
  int cxmax = dropTargetParent.getElement().getAbsoluteRight();
  int cymax = dropTargetParent.getElement().getAbsoluteBottom();
  final CoordinateArea ca = new CoordinateArea(cxmin,
                         cymin,
                         cxmax,
                         cymax);
  //Display Compass if not already visible
  if (!popup.isAttached()) {
    popup.setPopupPositionAndShow(new PopupPanel.PositionCallback() {
      @Override
      public void setPosition(int offsetWidth,
                  int offsetHeight) {
        popup.setPopupPosition(ca.getCenter().getLeft() - (offsetWidth / 2),
                    ca.getCenter().getTop() - (offsetHeight / 2));
      }
    });
  } else {
    popup.setPopupPosition(ca.getCenter().getLeft() - (popup.getOffsetWidth() / 2),
                ca.getCenter().getTop() - (popup.getOffsetHeight() / 2));
  }
}

private void show( final DragContext context ) {
  //Get centre of DropTarget
  final Widget dropTargetParent = context.dropController.getDropTarget();
  int cxmin = dropTargetParent.getElement().getAbsoluteLeft();
  int cymin = dropTargetParent.getElement().getAbsoluteTop();
  int cxmax = dropTargetParent.getElement().getAbsoluteRight();
  int cymax = dropTargetParent.getElement().getAbsoluteBottom();
  final CoordinateArea ca = new CoordinateArea( cxmin,
      cymin,
      cxmax,
      cymax );
  //Display Compass if not already visible
  if ( !isAttached() ) {
    setPopupPositionAndShow( new PositionCallback() {
      @Override
      public void setPosition( int offsetWidth,
                   int offsetHeight ) {
        setPopupPosition( ca.getCenter().getLeft() - ( offsetWidth / 2 ),
            ca.getCenter().getTop() - ( offsetHeight / 2 ) );
      }
    } );
  } else {
    setPopupPosition( ca.getCenter().getLeft() - ( getOffsetWidth() / 2 ),
        ca.getCenter().getTop() - ( getOffsetHeight() / 2 ) );
  }
}

private void show(final DragContext context) {
  //Get centre of DropTarget
  final Widget dropTargetParent = context.dropController.getDropTarget();
  int cxmin = dropTargetParent.getElement().getAbsoluteLeft();
  int cymin = dropTargetParent.getElement().getAbsoluteTop();
  int cxmax = dropTargetParent.getElement().getAbsoluteRight();
  int cymax = dropTargetParent.getElement().getAbsoluteBottom();
  final CoordinateArea ca = new CoordinateArea(cxmin,
                         cymin,
                         cxmax,
                         cymax);
  //Display Compass if not already visible
  if (!popup.isAttached()) {
    popup.setPopupPositionAndShow(new PopupPanel.PositionCallback() {
      @Override
      public void setPosition(int offsetWidth,
                  int offsetHeight) {
        popup.setPopupPosition(ca.getCenter().getLeft() - (offsetWidth / 2),
                    ca.getCenter().getTop() - (offsetHeight / 2));
      }
    });
  } else {
    popup.setPopupPosition(ca.getCenter().getLeft() - (popup.getOffsetWidth() / 2),
                ca.getCenter().getTop() - (popup.getOffsetHeight() / 2));
  }
}