Tricks of the Windows Gam…ming Gurus (2nd Edition)/Disc2.iso/msdn_vcb/samples/vc98/vcoledb/consumer/complexdb/complexctl.cpp

C/C++ Source or Header | 1998-04-03 | 5KB | 187 lines

// ComplexCtl.cpp : Implementation of CComplexCtl
//
// This is a part of the Active Template Library.
// Copyright (C) 1996-1998 Microsoft Corporation
// All rights reserved.
//
// This source code is only intended as a supplement to the
// Active Template Library Reference and related
// electronic documentation provided with the library.
// See these sources for detailed information regarding the
// Active Template Library product.

#include "stdafx.h"
#include "ComplexDB.h"
#include "ComplexCtl.h"

/////////////////////////////////////////////////////////////////////////////
// CComplexCtl

HRESULT CComplexCtl::OnDraw(ATL_DRAWINFO& di)
{
    return S_OK;
}

STDMETHODIMP CComplexCtl::get_DataSource(DataSource** ppDataSource)
{
    *ppDataSource = m_spDataSource;

    return S_OK;
}

STDMETHODIMP CComplexCtl::putref_DataSource(DataSource* pDataSource)
{
    m_spDataSource = pDataSource;
    UpdateControl();

    return S_OK;
}

STDMETHODIMP CComplexCtl::get_DataMember(DataMember * pVal)
{
    *pVal = m_strDataMember.Copy();

    return S_OK;
}

STDMETHODIMP CComplexCtl::put_DataMember(DataMember newVal)
{
    m_strDataMember = newVal;
    UpdateControl();

    return S_OK;
}

STDMETHODIMP CComplexCtl::get_FieldName(BSTR * pVal)
{
    *pVal = m_strFieldName.Copy();

    return S_OK;
}

STDMETHODIMP CComplexCtl::put_FieldName(BSTR newVal)
{
    m_strFieldName = newVal;

    if (newVal != NULL)
        UpdateControl();

    return S_OK;
}

HRESULT CComplexCtl::GetRowset()
{
    ATLASSERT(m_spDataSource != NULL);
    HRESULT hr;

    // Close anything we had open and unadvise if necessary
    if (m_dwCookie != 0)
        AtlUnadvise(m_spRowPosition, IID_IRowPositionChange, m_dwCookie);
    CAccessorRowset<CManualAccessor>::Close();
    m_spRowPosition.Release();

    hr = m_spDataSource->getDataMember(m_strDataMember, IID_IRowPosition,
        (IUnknown**)&m_spRowPosition);
    if (FAILED(hr))
        return hr;

    return m_spRowPosition->GetRowset(IID_IRowset, (IUnknown**)&m_spRowset);
}

HRESULT CComplexCtl::UpdateControl()
{
    USES_CONVERSION;
    CBookmark<> bookmark;
    HRESULT     hr;
    BOOL        bUserMode;
    BYTE*       pBookmarkCopy;
    ULONG       nBookmarkSize;
    ULONG       nColumn, nEntries, nLength;

    // We can't do anything if the datasource hasn't been set
    if (m_spDataSource == NULL)
        return S_OK;

    m_nColumns = 0; // Reset the column count
    // Get the rowset from the data control
    hr = GetRowset();
    if (FAILED(hr))
        return hr;

    // Get the column information so we know the column names etc.
    hr = CAccessorRowset<CManualAccessor>::GetColumnInfo(&m_nColumns, &m_pColumnInfo, &m_pStrings);

    // If the field name hasn't been set then there is no data to retrieve
    if (m_strFieldName.m_str == NULL)
        return S_OK;

    // Check if we have bookmarks we can store
    if (m_pColumnInfo->iOrdinal == 0)
    {
        m_bHaveBookmarks = true;
        FreeBookmarkMemory();
        nBookmarkSize = m_pColumnInfo->ulColumnSize;
    }
    else
        m_bHaveBookmarks = false;

    GetAmbientUserMode(bUserMode);
    if (bUserMode == FALSE)
        return S_OK;    // Don't do anything else at design mode

    // Now we can create the accessor and bind the data
    // First of all we need to find the column ordinal from the name
    for (nColumn = 0; nColumn < m_nColumns; nColumn++)
    {
        if (m_pColumnInfo[nColumn].pwszName != NULL)
        {
            nLength = ocslen(m_pColumnInfo[nColumn].pwszName) + 1;
            if (memcmp(m_pColumnInfo[nColumn].pwszName, m_strFieldName.m_str, nLength * sizeof(OLECHAR)) == 0)
                break;
        }
    }

    // If we didn't find a match then return
    if (nColumn == m_nColumns)
        return S_OK;

    if (m_bHaveBookmarks)
        nEntries = 2;
    else
        nEntries = 1;
    CreateAccessor(nEntries, &m_data, sizeof(m_data));
    if (m_bHaveBookmarks)
        AddBindEntry(0, DBTYPE_BYTES, sizeof(m_data.bookmark), &m_data.bookmark);

    AddBindEntry(nColumn, DBTYPE_BSTR, sizeof(BSTR), &m_data.bstrData);
    hr = Bind();
    if (FAILED(hr))
        return hr;

    // Loop around and store each record in our list control
    m_ctlListBox.SendMessage(LB_RESETCONTENT, 0, 0);
    hr = MoveFirst();
    while (hr == S_OK)
    {
        if (m_bHaveBookmarks)
        {
            pBookmarkCopy = new BYTE[nBookmarkSize];
            if (pBookmarkCopy != NULL)
                memcpy(pBookmarkCopy, &m_data.bookmark, nBookmarkSize);

            m_apBookmark.Add(pBookmarkCopy);
        }
        m_ctlListBox.SendMessage(LB_ADDSTRING, 0, (LPARAM)OLE2T(m_data.bstrData));

        FreeRecordMemory();
        hr = MoveNext();
    }
    // Set the cursor to the beginning
    m_ctlListBox.SendMessage(LB_SETCURSEL, 0, 0);

    // Set up the sink so we know when the rowset is repositioned
    AtlAdvise(m_spRowPosition, GetUnknown(), IID_IRowPositionChange, &m_dwCookie);

    return S_OK;
}