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.
The type 'ESRI.ArcGIS.Display.RubberLineClass' has no constructors definedInterop type 'ESRI.ArcGIS.Display.SimpleMarkerSymbolClass' cannot be embedded. Use the applicable interface instead