Exception when using TaskDialogIndirect in MFC

Question

I am trying the following code because I want to use the Verification Check box feature:

const HICON hQuestionIcon = AfxGetApp()->LoadStandardIcon(IDI_QUESTION);
CString strTitle = CString();
CString strMainInstruction = CString();
CString strContent = CString();
CString strAdditional = CString();
CString strFooter = CString();
CString strExpand = CString();
CString strCollapse = CString();

ENSURE(strTitle.LoadString(AFX_IDS_APP_TITLE));
ENSURE(strMainInstruction.LoadString(IDS_STR_SUBMIT_STATS_MAIN_TEXT));
ENSURE(strContent.LoadString(IDS_STR_SUBMIT_STATS_CONTENT_TEXT));
ENSURE(strAdditional.LoadString(IDS_STR_SUBMIT_STATS_ADDITIONAL_TEXT));
ENSURE(strFooter.LoadString(IDS_STR_TASK_DIALOG_FOOTER));
ENSURE(strExpand.LoadString(IDS_STR_FIND_OUT_MORE));
ENSURE(strCollapse.LoadString(IDS_STR_COLLAPSE));

TASKDIALOGCONFIG sConfig = { 0 };
sConfig.cbSize = sizeof(TASKDIALOGCONFIG);
sConfig.hInstance = AfxGetResourceHandle();
sConfig.dwCommonButtons = TDCBF_YES_BUTTON | TDCBF_NO_BUTTON;
sConfig.hMainIcon = hQuestionIcon;
sConfig.pszMainInstruction = strMainInstruction.GetString();
sConfig.pszContent = strContent.GetString();
sConfig.pszExpandedControlText = strAdditional.GetString();
sConfig.pszFooter = strFooter.GetString();
sConfig.pszCollapsedControlText = strExpand.GetString();
sConfig.pszExpandedControlText = strCollapse.GetString();
sConfig.pszFooterIcon = TD_INFORMATION_ICON;
sConfig.pszVerificationText = _T("Stop displaying this message");
sConfig.cxWidth = CMeetingScheduleAssistantApp::DetectMessageBoxWidth();

int iButtonPressed = IDNO; // Default
BOOL bStopDisplayingMessage = FALSE;

TaskDialogIndirect(&sConfig, &iButtonPressed, NULL, &bStopDisplayingMessage);

if (bStopDisplayingMessage)
{
    CChristianLifeMinistryUtils::HidePromptToSubmitWorkbookDownloadStats();
}

return iButtonPressed;

But I am getting an exception:

I can do a regular CTaskDialog instead (without checkbox) and it is fine.

Answer 1

Whilst there are other problems with the code I showed you in the question, the resolution to the exception was setting the parent:

sConfig.hwndParent = GetSafeHwnd();

It is not disussed or mentioned here. I found it out by viewing the source. The TASKDIALOGCONFIG topic says it can be NULL though.

Either way, exception doesn't happen now.

---

Complete Code

const HICON hQuestionIcon = AfxGetApp()->LoadStandardIcon(IDI_QUESTION);
CString strTitle;
CString strMainInstruction;
CString strContent;
CString strAdditional;
CString strFooter;
CString strExpand;
CString strCollapse;

ENSURE(strTitle.LoadString(AFX_IDS_APP_TITLE));
ENSURE(strMainInstruction.LoadString(IDS_STR_SUBMIT_STATS_MAIN_TEXT));
ENSURE(strContent.LoadString(IDS_STR_SUBMIT_STATS_CONTENT_TEXT));
ENSURE(strAdditional.LoadString(IDS_STR_SUBMIT_STATS_ADDITIONAL_TEXT));
ENSURE(strFooter.LoadString(IDS_STR_TASK_DIALOG_FOOTER));
ENSURE(strExpand.LoadString(IDS_STR_FIND_OUT_MORE));
ENSURE(strCollapse.LoadString(IDS_STR_COLLAPSE));

TASKDIALOGCONFIG sConfig = { 0 };
sConfig.hwndParent = GetSafeHwnd();
sConfig.cbSize = sizeof(TASKDIALOGCONFIG);
sConfig.dwFlags = TDF_ENABLE_HYPERLINKS | TDF_USE_HICON_MAIN;
sConfig.hInstance = AfxGetResourceHandle();
sConfig.dwCommonButtons = TDCBF_YES_BUTTON | TDCBF_NO_BUTTON;
sConfig.hMainIcon = hQuestionIcon;
sConfig.pszMainInstruction = strMainInstruction.GetString();
sConfig.pszContent = strContent.GetString();
sConfig.pszExpandedInformation = strAdditional.GetString();
sConfig.pszFooter = strFooter.GetString();
sConfig.pszCollapsedControlText = strExpand.GetString();
sConfig.pszExpandedControlText = strCollapse.GetString();
sConfig.pszFooterIcon = TD_INFORMATION_ICON;
sConfig.pszVerificationText = _T("Stop displaying this message");
sConfig.cxWidth = CMeetingScheduleAssistantApp::DetectMessageBoxWidth();

int iButtonPressed = IDNO; // Default
BOOL bStopDisplayingMessage = FALSE;

HRESULT hResult = TaskDialogIndirect(&sConfig, &iButtonPressed, NULL, &bStopDisplayingMessage);
if (hResult == S_OK)
{
    if (bStopDisplayingMessage)
    {
        CChristianLifeMinistryUtils::HidePromptToSubmitWorkbookDownloadStats();
    }
}

return iButtonPressed;