S60: cleanup stack

如果是局部指针的话，需要这样（否则heap内的内存无法回收）：

void SafeFunctionL()
{
CAnotherClass* theObject = new (ELeave) CAnotherClass();
// Push to the cleanup stack before calling
// any methods that may leave.
CleanupStack::PushL(theObject);
// If leave happens here, theObject will still be
// deleted.
theObject ->InitializeL();
// Pop the object from the cleanup stack.
CleanupStack::Pop(theObject);
// And finally delete the object.
delete theObject;
// Alternatively, the last 2 lines of code can
// be expressed in one line, as follows:
// CleanupStack::PopAndDestroy(theObject);
}

而如果是类的成员变量，则可以放心大胆地如下：

void CTestClass::SafeFunctionL()
{
// Heap allocation of a member variable
iTheObject = new(ELeave) CAnotherClass();
iTheObject ->InitializeL(); // Safe for iTheObject
}