The SBJ MVC Framework - The Design View, Responding to Model Change

//------------------------------------------------------------------------------
// $Workfile: ControlledWndT.h $
// $Header: /SbjDev/SbjCore/ControlledWndT.h 3     11/12/08 2:22p Steve $
//
//	Copyright � 2008 SbjCat
// All rights reserved.
//
//
// *** Authors ***
//	 Steve Johnson
//
// $Revision: 3 $
//
//-----------------------------------------------------------------------------

#pragma once

#include "ControlledCmdTargetT.h"
#include "WndController.h"


namespace SbjCore
{
	namespace Mvc
	{
		/**
			template class wraps a CWnd or derivative to add a link to 
			a WndController class for processing messages.
			                                             			
			ControlledWndT is derived from ControlledCmdTargetT and adds 
			an override to CWnd::OnWndMsg in order to route messages 
			to the assigned WndController.  The ControlledWndT will set 
			the WndController in its constructor with a call to
			ControlledCmdTargetT::SetController. 
			
			\param _baseClass Any CWnd or derived class
		*/
		template<class _baseClass>
		class ControlledWndT : public ControlledCmdTargetT<_baseClass>
		{
		public:
			/// ctor
			ControlledWndT()
			{
			}

			/// dtor
			virtual ~ControlledWndT()
			{
				m_hWnd = NULL;
			}

		protected:
			/** routes Windows messages to the Controller.  
				
				If the Controller::HandleWndMsg method returns true, it signals that
				it has already handled the call to OnWndMsgDefault, otherwise, OnWndMsg 
				will call OnWndMsgDefault.
				
				see MFC documentation for further information on CWnd::OnWndMsg

				\return true if the message was handled, otherwise false.
			*/
			virtual BOOL OnWndMsg(UINT message,
				WPARAM wParam,					
				LPARAM lParam,					
				LRESULT* pResult)				
			{
				BOOL bRslt = false;
				try
				{
					if (message == WM_CREATE)
					{
						message = WM_CREATE;	
					}
					if (GetSafeHwnd() != NULL)
					{
						// do pre default handling
						if ((pTheController != NULL) && (message != WM_COMMAND) && (message != WM_NOTIFY))
						{ 
							WndController* pTheWndCtrlr = dynamic_cast<WndController*>(pTheController);
							if (pTheWndCtrlr->CallDefaultFirst(message))
							{
								// return _baseClass result
								bRslt = _baseClass::OnWndMsg(message, wParam, lParam, pResult);
								(void)pTheWndCtrlr->HandleWndMsg(message, wParam, lParam, pResult);
							}
							else
							{
								// return false to allow default processing
								bRslt = pTheWndCtrlr->HandleWndMsg(message, wParam, lParam, pResult);

								// do default handling
								if (!bRslt)
								{
									bRslt = _baseClass::OnWndMsg(message, wParam, lParam, pResult);
								}
							}
						}
						else
						{
							bRslt = _baseClass::OnWndMsg(message, wParam, lParam, pResult);
						}

					}
				}
				catch(...)
				{
					// ignore exceptions (I think)
				}

				return bRslt;
			}
			
			/*
				The following overrides are only here because the MFC versions called OnCmdMsg
				and OnWndMsg as CWnd::OnCmdMsg and CWnd::OnWndMsg which bypassed the overrides 
				presented in ControlledWndT.h and ControlledCmdTarget.h. 
			*/
			
			virtual BOOL OnChildNotify(UINT uMsg, WPARAM wParam, LPARAM lParam, LRESULT* pResult)
			{
#ifndef _AFX_NO_OCC_SUPPORT
				if (m_pCtrlSite != NULL)
				{
					// first forward raw OCM_ messages to OLE control sources
					LRESULT lResult = SendMessage(OCM__BASE+uMsg, wParam, lParam);
					if (uMsg >= WM_CTLCOLORMSGBOX && uMsg <= WM_CTLCOLORSTATIC &&
						(HBRUSH)lResult == NULL)
					{
						// for WM_CTLCOLOR msgs, returning NULL implies continue routing
						return FALSE;
					}
					if (pResult != NULL)
						*pResult = lResult;
					return TRUE;
				}
#endif

				return ReflectChildNotify(uMsg, wParam, lParam, pResult);
			}
			
			struct AFX_CTLCOLOR
			{
				HWND hWnd;
				HDC hDC;
				UINT nCtlType;
			};

			BOOL ReflectChildNotify(UINT uMsg, WPARAM wParam, LPARAM lParam, LRESULT* pResult)
			{
				// Note: reflected messages are send directly to CWnd::OnWndMsg
				//  and CWnd::OnCmdMsg for speed and because these messages are not
				//  routed by normal OnCmdMsg routing (they are only dispatched)

				switch (uMsg)
				{
					// normal messages (just wParam, lParam through OnWndMsg)
				case WM_HSCROLL:
				case WM_VSCROLL:
				case WM_PARENTNOTIFY:
				case WM_DRAWITEM:
				case WM_MEASUREITEM:
				case WM_DELETEITEM:
				case WM_VKEYTOITEM:
				case WM_CHARTOITEM:
				case WM_COMPAREITEM:
					// reflect the message through the message map as WM_REFLECT_BASE+uMsg
					return OnWndMsg(WM_REFLECT_BASE+uMsg, wParam, lParam, pResult);

					// special case for WM_COMMAND
				case WM_COMMAND:
					{
						// reflect the message through the message map as OCM_COMMAND
						int nCode = HIWORD(wParam);
						if (OnCmdMsg(0, MAKELONG(nCode, WM_REFLECT_BASE+WM_COMMAND), NULL, NULL))
						{
							if (pResult != NULL)
								*pResult = 1;
							return TRUE;
						}
					}
					break;

					// special case for WM_NOTIFY
				case WM_NOTIFY:
					{
						// reflect the message through the message map as OCM_NOTIFY
						NMHDR* pNMHDR = (NMHDR*)lParam;
						int nCode = pNMHDR->code;
						AFX_NOTIFY notify;
						notify.pResult = pResult;
						notify.pNMHDR = pNMHDR;
						return OnCmdMsg(0, MAKELONG(nCode, WM_REFLECT_BASE+WM_NOTIFY), &notify, NULL);
					}

					// other special cases (WM_CTLCOLOR family)
				default:
					if (uMsg >= WM_CTLCOLORMSGBOX && uMsg <= WM_CTLCOLORSTATIC)
					{
						// fill in special struct for compatiblity with 16-bit WM_CTLCOLOR
						AFX_CTLCOLOR ctl;
						ctl.hDC = (HDC)wParam;
						ctl.nCtlType = uMsg - WM_CTLCOLORMSGBOX;
						//ASSERT(ctl.nCtlType >= CTLCOLOR_MSGBOX);
						ASSERT(ctl.nCtlType <= CTLCOLOR_STATIC);

						// reflect the message through the message map as OCM_CTLCOLOR
						BOOL bResult = OnWndMsg(WM_REFLECT_BASE+WM_CTLCOLOR, 0, (LPARAM)&ctl, pResult);
						if ((HBRUSH)*pResult == NULL)
							bResult = FALSE;
						return bResult;
					}
					break;
				}

				return FALSE;   // let the parent handle it
			}
		};

	}
}

//*** Modification History ***
// $Log: /SbjDev/SbjCore/ControlledWndT.h $
// 
// 3     11/12/08 2:22p Steve
// Finished Generalization of Model  v2.0.1