Nested namespace can't be found in spite of including header file

Question

I have two projects, one is a sample (which compiles without error) and looks like this (first few lines shown only):

Working Example

#include "cinder/app/App.h"
#include "cinder/app/RendererGl.h"
#include "cinder/Surface.h"
#include "cinder/gl/gl.h"
#include "cinder/gl/Texture.h"
#include "cinder/Rand.h"
#include "cinder/qtime/QuickTimeGl.h"

using namespace ci;
using namespace ci::app;
using namespace std;

class QTimeAdvApp : public App {
  public:
    void prepareSettings( Settings *settings );
    void setup();

    void keyDown( KeyEvent event );
    void fileDrop( FileDropEvent event );

    void update();
    void draw();

    void addActiveMovie( qtime::MovieGlRef movie );
    void loadMovieUrl( const std::string &urlString );
    void loadMovieFile( const fs::path &path );

};

Note especially the line: void addActiveMovie( qtime::MovieGlRef movie );

The other project, which needs to make use of the same library (Quicktime OpenGL within LibCinder), tries to do something similar - one again an extract:

Use in Project

#pragma once

#include "AbstractContent.h"
#include "cinder/gl/Texture.h"
#include "cinder/Tween.h"
#include "AbstractTransition.h"
#include "cinder/qtime/QuickTimeGl.h"

namespace TH {

    class VideoContent : public AbstractContent {
    public:
        VideoContent();
        ~VideoContent();
        virtual void setup();
        void loadMovie(ci::Url url);
        void loadLocalMovie(ci::fs::path path);
        void setPreloadedMovie(ci::qtime::MovieGlRef movie);

This one throws a compiler error: No member named 'qtime' in namespace 'cinder'

Notice again the virtually identical line: void setPreloadedMovie(ci::qtime::MovieGlRef movie); In fact, you can use the full qualified name ci:qtime:MovieGlRef in the first example and it compiles just fine (as expected).

What on earth is going on here? Why does the "Use in Project" version throw a compiler error: No member named 'qtime' in namespace 'cinder'?

Just for clarity, the QuickTimeGl.h file in turn includes another file which definitely declares the namespace and the type def:

namespace cinder { namespace qtime {

typedef std::shared_ptr<class MovieGl>  MovieGlRef;

Am I missing something? I'm pretty sure I'm including the correct header file, as before, and even trying to use the fully qualified namespace but still the compiler doesn't find the definition?

Answer 1

Have you tried referencing the global namespace, with ::ci::qtime rather than simply ci::qtime? This should not make a difference, but sometimes C++ compilers trip over these kind of things.