AMBIENTS.CPP

/* 
 * AMBIENTS.CPP 
 * Patron Chapter 24 
 * 
 * Implementation of the ambient properties IDispatch on a 
 * tenant control site. 
 * 
 * Copyright (c)1993-1995 Microsoft Corporation, All Rights Reserved 
 * 
 * Kraig Brockschmidt, Microsoft 
 * Internet  :  kraigb@microsoft.com 
 * Compuserve:  >INTERNET:kraigb@microsoft.com 
 */ 
 
 
#include "patron.h" 
 
 
/* 
 * CImpIDispatch::CImpIDispatch 
 * CImpIDispatch::~CImpIDispatch 
 * 
 * Parameters (Constructor): 
 *  pTen            PCTenant of the tenant we're in. 
 *  pUnkOuter       LPUNKNOWN to which we delegate. 
 */ 
 
CImpIDispatch::CImpIDispatch(PCTenant pTen, LPUNKNOWN pUnkOuter) 
    { 
    m_cRef=0; 
    m_pTen=pTen; 
    m_pUnkOuter=pUnkOuter; 
    return; 
    } 
 
CImpIDispatch::~CImpIDispatch(void) 
    { 
    return; 
    } 
 
 
 
 
/* 
 * CImpIDispatch::QueryInterface 
 * CImpIDispatch::AddRef 
 * CImpIDispatch::Release 
 */ 
 
STDMETHODIMP CImpIDispatch::QueryInterface(REFIID riid, PPVOID ppv) 
    { 
    return m_pUnkOuter->QueryInterface(riid, ppv); 
    } 
 
STDMETHODIMP_(ULONG) CImpIDispatch::AddRef(void) 
    { 
    ++m_cRef; 
    return m_pUnkOuter->AddRef(); 
    } 
 
STDMETHODIMP_(ULONG) CImpIDispatch::Release(void) 
    { 
    m_cRef--; 
    return m_pUnkOuter->Release(); 
    } 
 
 
 
 
/* 
 * CImpIDispatch::GetTypeInfoCount 
 * CImpIDispatch::GetTypeInfo 
 * CImpIDispatch::GetIDsOfNames 
 * 
 * Unimplemented members, not needed for ambient properties. 
 */ 
 
STDMETHODIMP CImpIDispatch::GetTypeInfoCount(UINT *pctInfo) 
    { 
    *pctInfo=0; 
    return NOERROR; 
    } 
 
STDMETHODIMP CImpIDispatch::GetTypeInfo(UINT itinfo 
    , LCID lcid, ITypeInfo **pptInfo) 
    { 
    *pptInfo=NULL; 
    return ResultFromScode(E_NOTIMPL); 
    } 
 
STDMETHODIMP CImpIDispatch::GetIDsOfNames(REFIID riid 
    , OLECHAR **rgszNames, UINT cNames, LCID lcid, DISPID *rgDispID) 
    { 
    *rgszNames=NULL; 
    *rgDispID=NULL; 
    return ResultFromScode(E_NOTIMPL); 
    } 
 
 
 
 
/* 
 * CImpIDispatch::Invoke 
 * 
 * Purpose: 
 *  Calls a method in the dispatch interface or manipulates a 
 *  property. 
 * 
 * Parameters: 
 *  dispIDMember    DISPID of the method or property of interest. 
 *  riid            REFIID reserved, must be NULL. 
 *  lcid            LCID of the locale. 
 *  wFlags          USHORT describing the context of the invocation. 
 *  pDispParams     DISPPARAMS * to the array of arguments. 
 *  pVarResult      VARIANT * in which to store the result.  Is 
 *                  NULL if the caller is not interested. 
 *  pExcepInfo      EXCEPINFO * to exception information. 
 *  puArgErr        UINT * in which to store the index of an 
 *                  invalid parameter if DISP_E_TYPEMISMATCH 
 *                  is returned. 
 * 
 * Return Value: 
 *  HRESULT         NOERROR or a general error code. 
 */ 
 
 
STDMETHODIMP CImpIDispatch::Invoke(DISPID dispIDMember, REFIID riid 
    , LCID lcid, unsigned short wFlags, DISPPARAMS *pDispParams 
    , VARIANT *pVarResult, EXCEPINFO *pExcepInfo, UINT *puArgErr) 
    { 
    HRESULT     hr; 
    VARIANT     varResult; 
 
    if (IID_NULL!=riid) 
        return ResultFromScode(E_INVALIDARG); 
 
    /* 
     * We ignore lcid in this function.  A multilingual application 
     * might use it to determine the meaning of certain parameters 
     * or perhaps as an indication of how to format data like 
     * time, date, and currency or any other language or locale- 
     * sensitive data. 
     */ 
 
    /* 
     * Variable handling:  since ambient properties is just a 
     * collection of singular read-only values, we don't have to 
     * worry about input parameters. 
     */ 
 
    /* 
     * If the caller is not interested in the return value, then 
     * pVarResult is NULL.  But since we're dealing with ambient 
     * properties, there should always be an interest.  In any case, 
     * if we're given a NULL, we'll point it to a dummy structure so 
     * the rest of the code can assume that pVarResult is non-NULL. 
     */ 
    if(NULL==pVarResult) 
      pVarResult=&varResult; 
 
    VariantInit(pVarResult); 
 
    //The most common case is boolean, use as an initial type 
    V_VT(pVarResult)=VT_BOOL; 
 
    /* 
     * Process the requested ambient property.  Anything but a 
     * request for a property is invalid, so we can check that 
     * before looking at the specific ID.  We can only get away 
     * with this because all properties are read-only. 
     */ 
 
    if (!(DISPATCH_PROPERTYGET & wFlags)) 
        return ResultFromScode(DISP_E_MEMBERNOTFOUND); 
 
    hr=NOERROR; 
 
    switch (dispIDMember) 
        { 
        case DISPID_AMBIENT_BACKCOLOR: 
            V_I4(pVarResult)=m_pTen->m_clrBack; 
            V_VT(pVarResult)=VT_I4; 
            break; 
 
        case DISPID_AMBIENT_FORECOLOR: 
            V_I4(pVarResult)=m_pTen->m_clrFore; 
            V_VT(pVarResult)=VT_I4; 
            break; 
 
        case DISPID_AMBIENT_FONT: 
            /* 
             * If we failed to create the font, act like we 
             * don't support it. 
             */ 
            if (NULL==m_pTen->m_pIFont) 
                return ResultFromScode(DISP_E_MEMBERNOTFOUND); 
 
            //The correct type is an IFontDisp pointer 
            V_DISPATCH(pVarResult)=m_pTen->m_pIFont; 
            m_pTen->m_pIFont->AddRef(); 
            V_VT(pVarResult)=VT_FONT; 
            break; 
 
        case DISPID_AMBIENT_LOCALEID: 
            V_I4(pVarResult)=m_pTen->m_lcid; 
            V_VT(pVarResult)=VT_I4; 
            break; 
 
        case DISPID_AMBIENT_USERMODE: 
            V_BOOL(pVarResult)=!m_pTen->m_fDesignMode; 
            break; 
 
        case DISPID_AMBIENT_UIDEAD: 
            V_BOOL(pVarResult)=m_pTen->m_fUIDead; 
            break; 
 
        case DISPID_AMBIENT_SUPPORTSMNEMONICS: 
            V_BOOL(pVarResult)=TRUE; 
            break; 
 
        case DISPID_AMBIENT_SHOWGRABHANDLES: 
            V_BOOL(pVarResult)=m_pTen->m_fHatchHandles; 
            break; 
 
        case DISPID_AMBIENT_SHOWHATCHING: 
            V_BOOL(pVarResult)=m_pTen->m_fHatchHandles; 
            break; 
 
        default: 
            hr=ResultFromScode(DISP_E_MEMBERNOTFOUND); 
            break; 
        } 
 
    return hr; 
    }