public CIMStroke ConstructStroke()

//Create a polygon graphic using an envelope with simple line and fill styles.

//Construct on the worker thread
await QueuedTask.Run(() =>
{
  //Build 2D envelope
  Coordinate2D env_ll = new Coordinate2D(1.0, 4.75);
  Coordinate2D env_ur = new Coordinate2D(3.0, 5.75);
  //At 2.x - Envelope env = EnvelopeBuilder.CreateEnvelope(env_ll, env_ur);
  Envelope env = EnvelopeBuilderEx.CreateEnvelope(env_ll, env_ur);

  //Set symbolology, create and add element to layout
  CIMStroke outline = SymbolFactory.Instance.ConstructStroke(
    ColorFactory.Instance.BlueRGB, 2.0, SimpleLineStyle.DashDotDot);
  CIMPolygonSymbol polySym = SymbolFactory.Instance.ConstructPolygonSymbol(
    ColorFactory.Instance.RedRGB, SimpleFillStyle.ForwardDiagonal, outline);
  //At 2.x - GraphicElement polyElm =
  //            LayoutElementFactory.Instance.CreatePolygonGraphicElement(layout, env, polySym);
  //         polyElm.SetName("New Polygon");
  GraphicElement polyElm = ElementFactory.Instance.CreateGraphicElement(
    layout, env, polySym, "New Polygon");
});

//Create a circle graphic element using a simple line and fill styles.

//Construct on the worker thread
await QueuedTask.Run(() =>
{
  //Build geometry
  Coordinate2D center = new Coordinate2D(2, 4);
  //At 2.x - EllipticArcBuilder eabCir = new EllipticArcBuilder(center, 0.5, esriArcOrientation.esriArcClockwise);
  var eabCir = new EllipticArcBuilderEx(center, 0.5, ArcOrientation.ArcClockwise);
  EllipticArcSegment cir = eabCir.ToSegment();

  //Set symbolology, create and add element to layout
  CIMStroke outline = SymbolFactory.Instance.ConstructStroke(ColorFactory.Instance.BlackRGB, 2.0, SimpleLineStyle.Dash);
  CIMPolygonSymbol circleSym = SymbolFactory.Instance.ConstructPolygonSymbol(ColorFactory.Instance.RedRGB, SimpleFillStyle.Solid, outline);
  //At 2.x - GraphicElement cirElm = LayoutElementFactory.Instance.CreateCircleGraphicElement(layout, cir, circleSym);
  //         cirElm.SetName("New Circle");

  var polyLine = PolylineBuilderEx.CreatePolyline(cir);
  GraphicElement cirElm = ElementFactory.Instance.CreateGraphicElement(layout, polyLine, circleSym, "New Circle");
});

//Create an ellipse graphic with simple line and fill styles.

//Construct on the worker thread
await QueuedTask.Run(() =>
{
  //Build geometry
  Coordinate2D center = new Coordinate2D(2, 2.75);
  //At 2.x - EllipticArcBuilder eabElp = new EllipticArcBuilder(center, 0, 1, 0.45, esriArcOrientation.esriArcClockwise);
  var eabElp = new EllipticArcBuilderEx(center, 0, 1, 0.45, ArcOrientation.ArcClockwise);
  EllipticArcSegment ellipse = eabElp.ToSegment();

  //Set symbolology, create and add element to layout
  CIMStroke outline = SymbolFactory.Instance.ConstructStroke(ColorFactory.Instance.GreenRGB, 2.0, SimpleLineStyle.Dot);
  CIMPolygonSymbol ellipseSym = SymbolFactory.Instance.ConstructPolygonSymbol(ColorFactory.Instance.GreyRGB, SimpleFillStyle.Vertical, outline);
  //At 2.x - GraphicElement elpElm = LayoutElementFactory.Instance.CreateEllipseGraphicElement(layout, ellipse, ellipseSym);
  //         elpElm.SetName("New Ellipse");

  var polyLine = PolylineBuilderEx.CreatePolyline(ellipse);
  GraphicElement elpElm = ElementFactory.Instance.CreateGraphicElement(layout, polyLine, ellipseSym, "New Ellipse");
});