asked on

Calling a function in the Main application from a DLL

Hi,

There is this application that has a scenario like this:

Main Application:
SDI with CListView
BaseDialog

DLL:
MFC Extension DLL
Derived Dialog (base from BaseDialog)

I'm using dynamic loading to create an instance of the DeriveDialog and pass it to the BaseDialog so that I can manipulate the functions of DeriveDialog in the Main Application.

But this is the problem, how about if there is an event in the DeriveDialog that it needs to call a function in the Main Application?

I tried to pass a pointer of the main application to function inside the DerivedDialog (implemented also as virtual in the BaseDialog) but I'm having a link error when I call the function inside the main Application

Example:

Main Application: (Implemented as SDI with CListView)
TestView::Hello() - function
BaseDialog:
virtual void Test(TestView* m_pView)

DLL: (Implemented as MFC Extension DLL)
DerivedDialog:

void Test(TestView* m_pView)
{
m_pView->Hello() - Linking error
}

I hope someone can help on my problem.

Mhelinx

Roshan Davis

Use PostMessage.
Pass the view handle (not pointer) to the dll function
Good luck

mhelinx09

ASKER

Rosmon,

You're my savior!!!

Can you elaborate it? I checked MSDN but they have a small definition about it.

Thanks!!!

Mhelinx

Roshan Davis

Main Application: (Implemented as SDI with CListView)

in header
afx_msg long Hello();

#define WM_USER_HELLO WM_USER+100

BEGIN_MESSAGE_MAP()
ON_MESSAGE(WM_USER_HELLO, Hello)
END_MESSAGE_MAP()

TestView::Hello() - function

BaseDialog:
virtual void Test(HWND hWnd)

DLL: (Implemented as MFC Extension DLL)
DerivedDialog:

#define WM_USER_HELLO WM_USER+100

void Test(HWND hWnd)
{
::PostMessage(hWnd, WM_USER_HELLO, 0, 0);
}

Call this dll function from view like this

*pfnTest(this->m_hWnd);

here this->m_hWnd is the window handle of the View class

Good Luck

mhelinx09

ASKER

Many thanks rosmon,

How about if you have parameter on the function (e. g. CString)

TestView::Hello(CString sInput) - function

Thanks!

Mhelinx

ASKER CERTIFIED SOLUTION

Roshan Davis

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mhelinx09

ASKER

Thanks a lot savior.

This what I did.

Base Dialog:
GetHandle(HWND hWnd)
protected:
HWND m_hWndHandle;

Main Application:
GetHandle(this->hWnd);

DO you think this is safe?

Thanks again.
Mhelinx

Roshan Davis

Yes, its fine...