I was going through ArcObjects example on following linkWalkthrough_Building_custom_UI_elements .I followed same steps but I was getting error while initializing objects for following code.
ESRI.ArcGIS.Display.IRubberBand rubberBand = new ESRI.ArcGIS.Display.RubberLineClass() ISimpleMarkerSymbol simpleMarkerSymbol = new ESRI.ArcGIS.Display.SimpleMarkerSymbolClass() IMarkerElement markerElement = new MarkerElementClass()
etc I was not able to find exact reason why I was getting but may be due to version of ArcObjects.I am using .Net 4.0,Visual studio 2010, ArcObjects 10.2. I got following type of error
The type 'ESRI.ArcGIS.Display.RubberLineClass' has no constructors defined. Interop type 'ESRI.ArcGIS.Display.SimpleMarkerSymbolClass' cannot be embedded. Use the applicable interface instead.