C++ CCodeChainCtx::SetScreen方法代码示例

bool IDockScreenDisplay::EvalBool (const CString &sCode, bool *retbResult, CString *retsError)

//	EvalBool
//
//	Evaluates the given string

	{
	CCodeChainCtx Ctx;
	Ctx.SetScreen(m_pDockScreen);
	Ctx.SaveAndDefineSourceVar(m_pLocation);
	Ctx.SaveAndDefineDataVar(m_pData);

	char *pPos = sCode.GetPointer();
	ICCItem *pExp = Ctx.Link(sCode, 1, NULL);

	ICCItem *pResult = Ctx.Run(pExp);	//	LATER:Event
	Ctx.Discard(pExp);

	if (pResult->IsError())
		{
		*retsError = pResult->GetStringValue();
		Ctx.Discard(pResult);
		return false;
		}

	*retbResult = !pResult->IsNil();
	Ctx.Discard(pResult);

	return true;
	}

CSpaceObject *IDockScreenDisplay::EvalListSource (const CString &sString, CString *retsError)

//	EvalListSource
//
//	Returns the object from which we should display items

	{
	char *pPos = sString.GetPointer();

	//	See if we need to evaluate

	if (*pPos == '=')
		{
		CCodeChainCtx Ctx;
		Ctx.SetScreen(this);
		Ctx.SaveAndDefineSourceVar(m_pLocation);
		Ctx.SaveAndDefineDataVar(m_pData);

		ICCItem *pExp = Ctx.Link(sString, 1, NULL);

		ICCItem *pResult = Ctx.Run(pExp);	//	LATER:Event
		Ctx.Discard(pExp);

		if (pResult->IsError())
			{
			*retsError = pResult->GetStringValue();
			Ctx.Discard(pResult);
			return NULL;
			}

		//	Convert to an object pointer

		CSpaceObject *pSource;
		if (strEquals(pResult->GetStringValue(), DATA_FROM_PLAYER))
			pSource = m_pPlayer->GetShip();
		else if (strEquals(pResult->GetStringValue(), DATA_FROM_STATION)
				|| strEquals(pResult->GetStringValue(), DATA_FROM_SOURCE))
			pSource = m_pLocation;
		else
			pSource = Ctx.AsSpaceObject(pResult);

		Ctx.Discard(pResult);
		return pSource;
		}

	//	Otherwise, compare to constants

	else if (strEquals(sString, DATA_FROM_PLAYER))
		return m_pPlayer->GetShip();
	else
		return m_pLocation;
	}

bool IDockScreenDisplay::EvalString (const CString &sString, bool bPlain, ECodeChainEvents iEvent, CString *retsResult)

//	EvalString
//
//	Evaluates the given string.

	{
	CCodeChainCtx Ctx;
	Ctx.SetEvent(iEvent);
	Ctx.SetScreen(m_pDockScreen);
	Ctx.SaveAndDefineSourceVar(m_pLocation);
	Ctx.SaveAndDefineDataVar(m_pData);

	return Ctx.RunEvalString(sString, bPlain, retsResult);
	}

ALERROR CDockScreenCustomList::OnInitList (SInitCtx &Ctx, CString *retsError)

//	OnInitList
//
//	Initialize list

	{
	//	Get the list element

	CXMLElement *pListData = Ctx.pDesc->GetContentElementByTag(LIST_TAG);
	if (pListData == NULL)
		return ERR_FAIL;

	//	See if we define a custom row height

	CString sRowHeight;
	if (pListData->FindAttribute(ROW_HEIGHT_ATTRIB, &sRowHeight))
		{
		CString sResult;
		if (!EvalString(sRowHeight, false, eventNone, &sResult))
			{
			*retsError = sResult;
			return ERR_FAIL;
			}

		int cyRow = strToInt(sResult, -1);
		if (cyRow > 0)
			m_pItemListControl->SetRowHeight(cyRow);
		}

	//	Get the list to show

	CCodeChain &CC = g_pUniverse->GetCC();
	ICCItem *pExp = CC.Link(pListData->GetContentText(0), 0, NULL);

	//	Evaluate the function

	CCodeChainCtx CCCtx;
	CCCtx.SetScreen(m_pDockScreen);
	CCCtx.SaveAndDefineSourceVar(m_pLocation);
	CCCtx.SaveAndDefineDataVar(m_pData);

	ICCItem *pResult = CCCtx.Run(pExp);	//	LATER:Event
	CCCtx.Discard(pExp);

	if (pResult->IsError())
		{
		*retsError = pResult->GetStringValue();
		return ERR_FAIL;
		}

	//	Set this expression as the list

	m_pItemListControl->SetList(CC, pResult);
	CCCtx.Discard(pResult);

	//	Position the cursor on the next relevant item

	SelectNextItem();

	//	Give the screen a chance to start at a different item (other
	//	than the first)

	CString sInitialItemFunc = pListData->GetAttribute(INITIAL_ITEM_ATTRIB);
	if (!sInitialItemFunc.IsBlank())
		{
		bool bMore = IsCurrentItemValid();
		while (bMore)
			{
			bool bResult;
			if (!EvalBool(sInitialItemFunc, &bResult, retsError))
				return ERR_FAIL;

			if (bResult)
				break;

			bMore = SelectNextItem();
			}
		}

	return NOERROR;
	}