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&sc.Subgraph.ElementAt(0)

&sc.Subgraph.GetAt(0)

sc.Subgraph.GetPointer()

// The top of every source code file must include this line
#include "sierrachart.h"

// For reference, refer to this page:
// Advanced Custom Study Interface and Language (ACSIL)

// This line is required. Change the text within the quote
// marks to what you want to name your group of custom studies.
SCDLLName("SC Subgraph Pointer Issue")


SCSFExport scsf_SC_Subgraph_Pointer_Issue(SCStudyInterfaceRef sc)
{
// Set configuration variables
if (sc.SetDefaults)
{
// Set the configuration and defaults
sc.GraphName = "Subgraph Pointer issue test";
sc.StudyDescription = "Setting subgraphs using pointers does not work.";
    
// Set the region to draw the graph in. Region zero is the main
// price graph region.
sc.AutoLoop = 0; // Manual Looping
sc.GraphRegion = 0;
sc.ValueFormat = 0;
sc.UpdateAlways = 0;


SCSubgraphRef subg = sc.Subgraph[0];
subg.Name = "Chart Scale";
subg.LineWidth = 3;
subg.DrawStyle = DRAWSTYLE_LINE;
subg.PrimaryColor = RGB(0, 128, 255); //Blue
subg.SecondaryColor = RGB(0, 0, 0); //black
subg.SecondaryColorUsed = true;
subg.DisplayNameValueInWindowsFlags = 1;

// ---->> THIS IS RAISING AN EXCEPTION WHEN USING GetAt
// WHEN USING ElementAt is used no exception is raised
// s_SCSubgraph_260* subgP = &sc.Subgraph.ElementAt(0);
s_SCSubgraph_260* subgP = &sc.Subgraph.GetAt(0);
subgP++;
subgP->Name = "Set via pointer from sc.Subgraph.GetPointer()";
subgP->LineWidth = 3;
subgP->DrawStyle = DRAWSTYLE_LINE;
subgP->PrimaryColor = RGB(128, 128, 255);
subgP->SecondaryColor = RGB(0, 0, 0); //black
subgP->SecondaryColorUsed = false;
subgP->DisplayNameValueInWindowsFlags = 1;


SCInputRef inp = sc.Input[0];
inp.Name = "Input via sc.Inpput[0]";
inp.SetInt(55);

// ---->> THIS IS NOT RAISING AN EXCEPTION
// s_SCInput_145* inpP = &sc.Input.ElementAt(0);
s_SCInput_145* inpP = &sc.Input.GetAt(0);
inpP++;
inpP->Name = "Input via pointer from GetAt()";
inpP->SetInt(99);

// Must return before doing any data processing if sc.SetDefaults is set
return;
}  
}

sc.Subgraph.ElementAt(0)

sc.Subgraph[0]

template <typename T>
class c_ArrayWrapper
{
  private:
    T* m_Data; //<<<----- POINTER TO ARRAY ELEMENT
    int m_NumElements;

    fp_SCDLLOnArrayUsed m_fp_OnArrayUsed;
    int m_OnArrayUsedParam;

    int m_NumExtendedElements;
    int m_TotalNumElements;

    T m_DefaultElement;

  public:
    c_ArrayWrapper()
    {
      ResetMembers();
    }

    T& operator [] (int Index) //<<<---- OPERATOR OVERLOADING from [index] to ElementAt(index)
    {
      return ElementAt(Index);
    }

    const T& operator [] (int Index) const
    {
      return ElementAt(Index);
    }

    T& ElementAt(int Index) //<<<--- ElementAt IS VERY SIMILAR TO GetAt BUT CHECKS IN ADDITION THE STATUS OF THE index AND m_Data
    {
      if (m_Data == NULL)
      {
        if (m_fp_OnArrayUsed != NULL)
        {
          // This will allocate and set up the array if it can
          m_fp_OnArrayUsed(m_OnArrayUsedParam);
        }

        if (m_Data == NULL)
          return m_DefaultElement;
      }

      if (m_TotalNumElements == 0)
        return m_DefaultElement;

      if (Index < 0)
        Index = 0;

      if (Index >= m_TotalNumElements)
        Index = m_TotalNumElements - 1;

      return m_Data[Index]; //<<<--- THIS IS JUST A DIFFERENT WRITING OF *(m_data + Index) RETURNING A REFERENCE TO INDEX ELEMENT
}

    T& GetAt(int Index)
    {
      return m_Data[Index]; //<<<--- THIS IS JUST A DIFFERENT WRITING OF *(m_data + Index) RETURNING A REFERENCE TO INDEX ELEMENT
    }

    }


    // This should only be used when absolutely necessary and you know what
    // you are doing with it.
    T* GetPointer()
    {
      //Returns non-constant data pointer which can be used for rapidly setting blocks of data
      return m_Data;
    }