No appropriate default constructor available?

Question

I've got a peculiar error writing some C++/CLI code. I'm trying to make a copy of a class which holds some data.

The class is defined as:

public ref class RawDataPacket
{
protected:
    float* m_internalData;

public:
    RawDataPacket(const float* newInternalData);
    RawDataPacket(const RawDataPacket^ rdp);
    RawDataPacket(RawDataPacket^ rdp);
    RawDataPacket();
};

When I try and make use of the class as follows:

void SomeClass::SomeFunction( RawDataPacket^ rdp )
{
    // Send a copy of the packet to anyone interested.
    RawDataPacket^ rdp1 = gcnew RawDataPacket( rdp );
    ForwardData( rdp1 );
}

I get:

error C2512: 'RawDataPacket' : no appropriate default constructor available

I thought that RawDataPacket(); had that covered? ..or am I missing something really obvious there?

[Edit] The body of RawDataPacket() looks like this:

RawDataPacket::RawDataPacket()
{
    m_internalData = nullptr;
}

[Edit2] The full compiler output looks like this:

1>------ Build started: Project: MySoftware, Configuration: Debug Win32 ------
1>Compiling...
1>RawDataPacket.cpp
1>Controller.cpp
1>.\Controller.cpp(452) : error C2512: 'MySoftware::RawDataPacket' : no appropriate default constructor available
1>Build log was saved at "file://c:\Projects\Experiments\MySoftware\Debug\BuildLog.htm"
1>MySoftware - 1 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 1 up-to-date, 0 skipped ==========

Solution 1

Got it! It occurred to me that I'd forward-declared the RawDataPacket class in the header of the Controller class.

I tried including the header in there and removing the forward declaration and it worked. So it turns out that despite forward-declaring the class I'd forgotten to include the header in Controller.cpp

That could have been a nasty one to find.. cheers for the help all!

Solution 2

use explicit before the constructor if you are having parameters for constructor.