Loading a FormView based on the Screen Resolution

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When you generate a formview based application or generally when you are using formview derived class, you will find this piece of code.

CTempView::CTempView()
 : CFormView(CTempView::IDD)
{
 //{{AFX_DATA_INIT(CTempView)
 //}}AFX_DATA_INIT
}

Now depending upon the resolution you want to load the resource i.e. for 1024×768 you want to load CTempView::IDD and for 800×600 you want to load CTempView::IDD1. If you try to write the code for selecting the resource directly in the constructor i.e. something like this

CTempView::CTempView()
 {
    /*logic to find the resolution, bResol will be true if it is 1024x768*
    if(bResol)
        id = CTempView::IDD;
   else
        id = CTempView::IDD1;

  // Call the formview costructor here.
  CFormView(id);

 //{{AFX_DATA_INIT(CTempView)
 //}}AFX_DATA_INIT

}
!-- end the block of source code -->

The Compiler will crib and it will not compile.

The solution is to have a global object which gets constructed before the formview and assign a global variable with the appropriate resource id, so that it can be used in the FormView constructor. The code looks something like this.

static int g_ID;
static struct _stDummy
{
 _stDummy()
 {
  /* logic to find the resolution *
  int x = GetSystemMetrics(SM_CXSCREEN);
  if(x == 1024)
   g_ID = CTempView::IDD;
  else /* for 800x600 and any other resolution*
   g_ID = CTempView::IDD1;
 }
}g_Dummy; /* dummy object *

IMPLEMENT_DYNCREATE(CTempView, CFormView)
CTempView::CTempView() :CFormView(g_ID)
{
 //{{AFX_DATA_INIT(CTempView)
 //}}AFX_DATA_INIT
}
!-- end the block of source code -->

Now the g_Dummy object gets constructed first and your logic for selecting the resource id is done here and the id is stored in g_ID which is later being used in the formview constructor. Now the compiler works happily and so does the code.