IDE Debug Helpers

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IDE debug helpers

Qt Creator

Qt Creator directly supports introspection of all Qt Containers and QObject derived classes for Qt 4 and Qt 5. User defined types can be supported in addition, see the Qt Creator documentation for details.

MS visual studio QString & QByteArray expansions

The new layout of QString in Qt 5 is hard to inspect using the debugger. The following code can be added to autoexp.dat (c:files(x86)visual studio 9.0\common7\packages\debugger\autoexp.dat) You should add it to the [Visualizer] section, before the STL/ATL containers.

Qt types

QStringData{

preview ([(unsigned short*)$e.d + 2 + $e.offset,su])
stringview ([(unsigned short*)$e.d + 2 + $e.offset,sub])

} QString{

preview ([$e.d])

} QByteArrayData{

preview ([(unsigned char*)$e.d + 4 + $e.offset,s])
stringview ([(unsigned char*)$e.d + 4 + $e.offset,sb])

} QByteArray{

preview ([$e.d])

}

Unfortunately, sizeof() cannot be used. That is why there is a constant 2 or 4 for the offset pointer. For an x64 build, the sizes most likely need to be doubled.

MS Visual Studio 2012

There is a new way to visualize native type, see http://code.msdn.microsoft.com/Writing-type-visualizers-2eae77a2 for details.

Ready-made .natvis files are included in the Visual Studio add-in.

So we can visualize QString and some other types using qt5.natvis file (save to file: %USERPROFILE%\Documents\Visual Studio 2012\Visualizers\qt5.natvis) <?xml version="1.0" encoding="utf-8"?> <AutoVisualizer >

<Type Name="QString">

<DisplayString>{(char*)d + d->offset,su}</DisplayString>
</Type>

<Type Name="QtPrivate::RefCount">

<DisplayString>{atomic}</DisplayString>
</Type>

<Type Name="QBasicAtomicInteger<int>">

<DisplayString>{_q_value}</DisplayString>
</Type>

<Type Name="QTypedArrayData<>">

<DisplayString>{{Count = {size}}}</DisplayString>
<Expand>
<Item Name="[size]">size</Item>
<ArrayItems>
<Size>size</Size>
<ValuePointer>(iterator) ((char)this + offset)</ValuePointer>
</ArrayItems>
</Expand>
</Type>

<Type Name="QByteArray">

<DisplayString>{*d}</DisplayString>
</Type>

<!— More Qt5 types… —>

</AutoVisualizer>

MS Visual Studio 2013

The ".natvis" files introduced in MSVS2012 received some additional attention in MSVS2013:

http://blogs.msdn.com/b/vcblog/archive/2013/06/28/using-visual-studio-2013-to-write-maintainable-native-visualizations-natvis.aspx