漫谈WinCE输入法的编写(三)

//========================================================================
//TITLE:
//    漫谈WinCE输入法的编写(三)
//AUTHOR:
//    norains
//DATE:
//    Friday  2-March -2007
//Environment:
//        EVC4.0 + Standard SDK
//========================================================================
       
        这次就让我们来看看一个简单的输入法界面窗口的实现.如果以类的观点来看,输入法界面窗口和普通的应用程序的窗口没有什么不同,可能也是唯一最大的差异就是输入法窗口不能也不应该发送PostQuiteMessage,否则将导致输入法管理器的退出.
       
        闲话不表,直接来看看一个最简单的输入法窗口架构:

        //**************************************************************
        //IMWnd.h
        //*************************************************************
        //The input method window class
        class CIMWnd  
        ...{
        public:
            //获取对象实例
            static CIMWnd * GetInstance();
            //显示输入法的设置窗口
            void ShowUserOptionsDlg(HWND hWndParent,HINSTANCE hInst = NULL);
            //显示输入法界面
            void ShowWindow(BOOL bShow);
            //销毁输入法界面
            void DestroyWindow();            
            //初始化窗口,hWndSip是输入法管理器的句柄
            BOOL Initialize(HINSTANCE hInst, HWND hWndSip);
            //析构函数
            virtual ~CIMWnd();
            
        protected:        
            //构造函数
            CIMWnd();    
            //注册回调函数        
            void OnRegCallback(HWND hWnd,UINT wMsg,WPARAM wParam,LPARAM lParam);    
            //窗口过程    
            static LRESULT WndProc(HWND hWnd,UINT wMsg,WPARAM wParam,LPARAM lParam);
            //指向对象的指针
            static CIMWnd *m_pInstance;        
            //输入法窗口句柄    
            HWND m_hWnd;
            //DLL实例
            HINSTANCE m_hInst;
            //输入法管理器窗口句柄
            HWND m_hWndSip; 
            //保存对外回调函数的指针        
            IIMCallback *m_pIMCallback; //Pointer to the callback function
        
        
        };

        //**************************************************************
        //IMWnd.cpp
        //*************************************************************
    
        //Initialize
        CIMWnd *CIMWnd::m_pInstance = NULL;        
        
        //----------------------------------------------------------------------
        //Description:
        //    Get the object instance
        //----------------------------------------------------------------------
        CIMWnd * CIMWnd::GetInstance()
        ...{
            if(m_pInstance == NULL)
            ...{
                m_pInstance = new CIMWnd();
            }
            return m_pInstance;
        }
        
        
        //----------------------------------------------------------------------------
        //Decription:
        //    On message MSG_USEROPTIONSDLG
        //-----------------------------------------------------------------------------
        void CIMWnd::ShowUserOptionsDlg(HWND hWndParent,HINSTANCE hInst)
        ...{
            
            CSettingDlg *pSettingDlg;
            pSettingDlg = CSettingDlg::GetInstance();
        
            if(hInst == NULL)
            ...{
                pSettingDlg->ShowDlg(m_hInst,hWndParent,&m_iTimeFresh);
            }
            else
            ...{
                pSettingDlg->ShowDlg(hInst,hWndParent,&m_iTimeFresh);
            }    
        
        }
        
        
        //----------------------------------------------------------------------
        //Description:
        //    Show the window
        //----------------------------------------------------------------------
        void CIMWnd::ShowWindow(BOOL bShow)
        ...{
            if(bShow == TRUE)
            ...{
                ::ShowWindow(m_hWnd,SW_SHOW);
            }
            else
            ...{
                ::ShowWindow(m_hWnd,SW_HIDE);
            }
        }
        
        //----------------------------------------------------------------------
        //Description:
        //    Destroy the window
        //----------------------------------------------------------------------
        void CIMWnd::DestroyWindow()
        ...{
            ::DestroyWindow(m_hWnd);
            UnregisterClass(WINDOW_CLASS,m_hInst);
        }
        
        
        
        //----------------------------------------------------------------------
        //Description:
        //    Initialize
        //----------------------------------------------------------------------
        BOOL CIMWnd::Initialize(HINSTANCE hInst, HWND hWndSip)
        ...{
            m_hInst = hInst;
            m_hWndSip = hWndSip;
        
        
            WNDCLASS wc;
            wc.style = CS_VREDRAW | CS_HREDRAW;;
            wc.lpfnWndProc = WndProc; 
            wc.cbClsExtra = 0;
            wc.cbWndExtra = 0;
            wc.hInstance = hInst;
            wc.hIcon = NULL;
            wc.hCursor = NULL;
            wc.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
            wc.lpszMenuName = NULL;
            wc.lpszClassName = WINDOW_CLASS;
            if(RegisterClass(&wc) == 0)
            ...{
                return FALSE;
            }
        
          // Create SIP window.  
            m_hWnd = CreateWindowEx(0,
                                WINDOW_CLASS,
                                WINDOW_TITLE,
                                WS_CHILD | WS_BORDER ,
                                CW_USERDEFAULT,
                                CW_USERDEFAULT,
                                CW_USERDEFAULT,
                                CW_USERDEFAULT,
                                hWndSip,
                                NULL,
                                m_hInst,
                                NULL
                                );
                    
        
            if(IsWindow(m_hWnd)==FALSE)
            ...{
                return FALSE;
            }
        
            return TRUE;
        }
        
        
        CIMWnd::~CIMWnd()
        ...{    
            DeleteCriticalSection(&m_CriticalForWaitFresh);
            if(m_pInstance != NULL)
            ...{
                delete m_pInstance;
                m_pInstance = NULL;
            }
        }
        
        
        CIMWnd::CIMWnd()
        ...{
        
            m_pIMCallback = NULL;
            m_hWnd = NULL;
            m_hInst = NULL;
            m_hWndSip = NULL;
        }
        
        
        //----------------------------------------------------------------------------
        //Decription:
        //    On message MYMSG_REGCALLBACK
        //-----------------------------------------------------------------------------
        void CIMWnd::OnRegCallback(HWND hWnd, UINT wMsg, WPARAM wParam, LPARAM lParam)
        ...{
            m_pIMCallback = (IIMCallback *)wParam;
        }
        
        
        
        //----------------------------------------------------------------------
        //Description:
        //    Window process
        //----------------------------------------------------------------------
        LRESULT CIMWnd::WndProc(HWND hWnd, UINT wMsg, WPARAM wParam, LPARAM lParam)
        ...{
            switch(wMsg)
            ...{
                ...
            
                case MYMSG_REGCALLBACK:
                    m_pInstance->OnRegCallback(hWnd,wMsg,wParam,lParam);
                    return 0;
            
                ...
            }
            return DefWindowProc(hWnd,wMsg,wParam,lParam);
        }

        这里需要注意的是m_pIMCallback指针,它保存的是输入法管理器传回来的函数地址,我们可以通过这个回调函数来像外发送字符.例如:m_pIMCallback->SendString(TEXT("，"),1);
               
        MYMSG_REGCALLBACK是自定义的消息,用来通知输入法窗口来保存函数地址.该消息的发送是在CInputMethod类的RegisterCallback()函数中.
       
       
        一个简单的输入法架构基本上已经完成,在下一章中将介绍一些输入法的调试技巧和需要注意的问题.