Creating measurement studio control dynamically in VC++7.0

Question

We downloaded an example from the
following site:
<http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=B45EACE3EFE056A4E034080020E74861&p_...>
We converted the project to VC++7.0
solution.
When we tried to create a single
control it worked fine.
But when we create the second control
it crashes.
void CDynamicControlDlg:nButton1()
        CNiReal64Vector rt;                
        CNiMath:ineWave(rt, 60, 1.0);
        BSTR bstrLic = :ysAllocStringLen(pwchUILic, sizeof (pwchUILic) /
sizeof(WCHAR));
        m_graph1.Create("", WS_VISIBLE, CRect(110,20,370,200),this, 0,NULL,
FALSE, bstrLic);
        m_graph1.PlotY(rt);                
        :ysFreeString(bstrLic);              
        ::AfxMessageBox("WAIT for the crash.....");
        BSTR bstrLic1 = :ysAllocStringLen(pwchUILic, sizeof (pwchUILic) /
sizeof(WCHAR));
        m_graph2.Create("", WS_VISIBLE, CRect(200,120,350,300),this, 0,NULL,
FALSE, bstrLic1);
        m_graph2.PlotY(rt);                
        :ysFreeString(bstrLic1);    

Answer 1

Each control needs to have a unique ID, which is what the 5th parameter
in the Create method is. Try changing the code to the following
BSTR bstrLic = :ysAllocStringLen(pwchUILic, sizeof (pwchUILic) /
sizeof(WCHAR));
        m_graph1.Create("", WS_VISIBLE, CRect(110,20,370,200),this, 0,NULL,
FALSE, bstrLic);
        m_graph1.PlotY(rt);                
        :ysFreeString(bstrLic);              
        ::AfxMessageBox("WAIT for the crash.....");
        BSTR bstrLic1 = :ysAllocStringLen(pwchUILic, sizeof (pwchUILic) /
sizeof(WCHAR));
        m_graph2.Create("", WS_VISIBLE, CRect(200,120,350,300),this, 1002,NULL,
FALSE, bstrLic1);
        m_graph2.PlotY(rt);                
        :ysFreeString(bstrLic1);    
What you were doing was giving two controls the same control ID (0 in
this case). MFC will assert in this case. I just chose 1002, but that
value will depend on how many controls you have on your dialog and what
IDs are available. So everytime you create a new control, make sure you give it an ID that is not being used by another control.
Hope this helps.
Message Edited by bilalD on 10-26-2005 09:17 AM
Bilal Durrani
NI