小编use*_*874的帖子

我有一个界面

Public Interface IPlotSurface2D
   WriteOnly Property PlotBackBrush() As IRectangleBrush
End Interface

这是实现接口的类

Public Class PlotSurface2D
    Implements IPlotSurface2D

    Public WriteOnly Property PlotBackBrush() As IRectangleBrush _
        Implements IPlotSurface2D.PlotBackBrush

        Set(value As IRectangleBrush)
            Me.plotBackBrush_ = DirectCast(value, IRectangleBrush)
            Me.plotBackColor_ = DirectCast(Nothing, Object)
            Me.plotBackImage_ = DirectCast(Nothing, Drawing.Bitmap)
        End Set
    End Property
End Class

我收到以下编译错误：

错误 86“PlotBackBrush”无法通过类“PlotSurface2D”在项目外部公开类型“IRectangleBrush”。

我怎样才能解决这个问题？