Getting messages from the IntelliMouse

The IntelliMouse (the mouse with the wheel in the center) is pretty neat. You can register to get the wheel messages from it in your top level frame. If you want to handle the message in a view you must pass the message down manually as is illustrated. To get messages from the wheel add the following to your application:

1. To make the wheel act like a simple middle button just add handlers for:

   WM_MBUTTONDOWN
   WM_MBUTTONUP

   and so-on just like left and right buttons. You won't find this in the class wizzard but you can add them manually.

 

2. For wheel messages do the following:

   Declare a global in your app as follows:

   UINT uMSH_MOUSEWHEEL;

   and everyplace else declare an external so you can get at it

   extern UINT uMSH_MOUSEWHEEL;

 

3. In your initialization code register the following message

   uMSH_MOUSEWHEEL = RegisterWindowMessage("MSWHEEL_ROLLMSG");

 

4. (In the MAIN FRAME add the following:

   To the message map in the .H file add

   afx_msg LONG OnWheel(UINT a, LONG b);

   To the message map in the .CPP file add

   ON_REGISTERED_MESSAGE(uMSH_MOUSEWHEEL,OnWheel) 

   And then add the message handler as follows

   LONG CMainFrame::OnMouseWheel(UINT nFlags, LONG pValue) 
   {
   	if(nFlags & 0x0100) // Rolled in
   	{
   		// do rolled in stuff here
   	}
   	else // Rolled out
   	{
   		// do rolled out stuff here
   	}
   	return 0;
   }

 

5. if you want to receive this message in a view then add the same handlers shown above to your view and then do the following in your main frame.

   LONG CMainFrame::OnWheel(UINT a, LONG b)
   {
   	BOOL yn;
   	MDIChildWnd* aw = (MDIChildWnd*)MDIGetActive(&yn); 
   	if(aw)
   	{
   		CView * junk;
   		junk = aw->GetActiveView();
   		if(junk)
   			junk->SendMessage(uMSH_MOUSEWHEEL,a,b);
   	}
   	return> 0;
   }