Unable to launch Qt Assistant

[Mark Brethen]

On Jul 14, 2014, at 6:22 PM, Mark Brethen <mark.brethen at gmail.com> wrote:

> I'm testing the FreeCAD build and discovered that the help menu returns the error message: "Unable to launch Qt Assistant (/opt/local/bin/Assistant.app/Contents/MacOS/Assistant)".  Launching Qt Assistant is done in the function startAssistant() which is found in src/Gui/Assistant.cpp. The following lines get the name of the executable and the doc path:
> 
> #ifdef Q_OS_WIN
>        QString app;
>        app = QDir::toNativeSeparators(QString::fromUtf8
>            (App::GetApplication().GetHomePath()) + QLatin1String("bin/"));
> #else
>        QString app = QLibraryInfo::location(QLibraryInfo::BinariesPath) + QDir::separator();
> #endif 
> #if !defined(Q_OS_MAC)
>        app += QLatin1String("assistant");
> #else
>        app += QLatin1String("Assistant.app/Contents/MacOS/Assistant");
> #endif
> 
>        QString exe = QString::fromUtf8(App::GetApplication().getExecutableName());
>        QString doc = QString::fromUtf8(App::Application::getHelpDir().c_str());
>        QString qhc = doc + exe.toLower() + QLatin1String(".qhc");
> 
> I'm not that familiar with c++ but I believe 'QLibraryInfo::location(QLibraryInfo::BinariesPath) + QDir::separator()' is setting the variable 'app' to /opt/local/bin. This line needs to be patched so that it finds /Applications/Macports/Qt4. How is a string used as a file path In c++?
> 
> 
> Mark
> 
> 
> 
> 

In other words, how is the macports variable included in the patch? 

QString app = ${applications_dir} + QLatin1String("Qt/");


Mark