ArcObjects 10.3向地圖添加透明多邊形

Question

這是我一直試圖解決的一個問題，並決定尋求幫助。我創建了一個ESRI ArcGIS Desktop加載項，允許用戶繪製多邊形，然後將其添加到地圖中。我能夠捕獲多邊形並將其添加到地圖，問題是透明度。目前和默認情況下，它是100％不透明和堅實。我想使它大約有50％的不透明度，以便用戶可以看到它背後的數據。

這裏是我到目前爲止的代碼：

 public static void AddPolygonToMap(IActiveView ActiveViewInstance, IGeometry NewGeo) 
    { 
     //Local Variable Declaration 
     var fillShapeElement = default(IFillShapeElement); 
     var element = default(IElement); 
     var graphicsContainer = default(IGraphicsContainer); 
     var simpleFilleSymbol = default(ISimpleFillSymbol); 
     var newRgbColor = default(IRgbColor); 
     var lineSymbol = default(ILineSymbol); 

     //Use the IElement interface to set the Envelope Element's geo 
     element = new PolygonElement(); 
     element.Geometry = NewGeo; 

     //QI for the IFillShapeElement interface so that the symbol property can be set 
     fillShapeElement = element as IFillShapeElement; 

     //Create a new fill symbol 
     simpleFilleSymbol = new SimpleFillSymbol(); 

     //Create a new color marker symbol of the color black; 
     newRgbColor = new RgbColor(); 
     newRgbColor.Red = 0; 
     newRgbColor.Green = 0; 
     newRgbColor.Blue = 0; 

     //Create a new line symbol so that we can set the width outline 
     lineSymbol = new SimpleLineSymbol(); 
     lineSymbol.Color = newRgbColor; 
     lineSymbol.Width = 2; 

     //Setup the Simple Fill Symbol 
     simpleFilleSymbol.Color = newRgbColor; 
     simpleFilleSymbol.Style = esriSimpleFillStyle.esriSFSHollow; 
     simpleFilleSymbol.Outline = lineSymbol; 
     fillShapeElement.Symbol = simpleFilleSymbol; 

     //QI for the graphics container from the active view allows access to basic graphics layer 
     graphicsContainer = ActiveViewInstance as IGraphicsContainer; 

     //Add the new element at Z order 0 
     graphicsContainer.AddElement((IElement)fillShapeElement, 0); 

     //Show the new graphic 
     ActiveViewInstance.Refresh(); 
    } 

我知道這是可能不知何故，我相信這只是一兩行失蹤，但任何幫助，將不勝感激。

V/R，

喬希

Answer 1

這看起來是要創建一個圖形元素。圖形元素不支持100％透明或0％透明以外的透明度。這是下面的文檔中列出：

IColor.Transparency物業 http://help.arcgis.com/en/sdk/10.0/arcobjects_net/componenthelp/index.html#//001w000000nt000000

For graphic elements, 0 for transparent and 255 for opaque are the only supported values. 

我希望這有助於！