UpdateBot: Nightly -> 4.5

2015-11-12T22:04:05Z

Nightly -> 4.5

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<noinclude>{{documentation/versioncheck}}</noinclude>

= Qt Plugins =
Plugins for Qt (e.g. designer, iconengines, image formats) are automatically discovered and loaded by Qt based on the directory plugins are into. There are [http://doc.qt.nokia.com/4.6/plugins-howto.html#locating-plugins multiple ways] to tell Qt where to scan directories containing plugins. <code>addLibraryPath</code> would probably be the easiest, but because plugins (e.g. designer) must be localized by Qt Designer when designing UIs, the solution is to have the environment variable <code>QT_PLUGIN_PATH</code> set by the [[Documentation/{{documentation/version}}/Developers/Launcher|Slicer launcher]] (or using a ''qt.conf'' file when no launcher is available (e.g. MacOsX Slicer installs)).
A limitation of qt.conf is that it only handles 1 plugin path, this is why Slicer installs must have their plugins in a unique top directory.

== Configuration ==
To create a plugin, use one of the macros in [https://github.com/commontk/CTK/blob/master/CMake/ctkMacroBuildQtPlugin.cmake ctkMacroBuildQtPlugin.cmake]:
*<code>ctkMacroBuildQtDesignerPlugin</code> to build a Qt Designer plugin.
*<code>ctkMacroBuildQtIconEnginesPlugin</code> to build an Icon Engine plugin.
*...
They are built in the ''bin/PLUGIN_TYPE'' directory where ''PLUGIN_TYPE'' is designer, imageformats... Only on Visual Studio they are also automatically in XXX-build/bin/PLUGIN_TYPE/BUILD_TYPE where BUILD_TYPE is Debug, Release...
Refer to

== Mac Bundle ==
Because Qt plugins are not ''direct'' dependency of Slicer (discovered and dynamically loaded at run time), Qt plugins need to be compiled as [http://www.cmake.org/cmake/help/cmake-2-8-docs.html#command:add_library MODULE] and need to be manually bundled at package time (see [http://viewvc.slicer.org/viewvc.cgi/Slicer4/trunk/Utilities/LastConfigureStep/SlicerCompleteBundles.cmake.in?view=markup SlicerCompleteBundles.cmake.in]).

== Build ==
<code>QT_PLUGIN_PATH</code> must points to 2 paths: ''Slicer-Superbuild/CTK-build/CTK-build/bin'' and <code>Slicer_QtPlugins_DIR</code>=''Slicer-Superbuild/Slicer-build/bin''.

The default Qt plugins (such as svg image format or sqldriver plugins) are in the Qtdir plugin path.

Plugins locations for Slicer builds:
* ''Slicer-Superbuild/CTK-build/CTK-build/bin/designer/CTK??????WidgetsPlugins.{so|dll}''
* ''Slicer-Superbuild/Slicer-build/bin/designer/qSlicer??????WidgetsPlugins.{so|dll}''
* ''Slicer-Superbuild/Slicer-build/bin/iconengines/qSlicer??????Plugin.{so|dll}''
* ''QtDir/plugins/imageformats/*.{so|dll|dylib}''

On Windows, they also are in the following paths but are ignored by Qt:
* ''Slicer-Superbuild/CTK-build/CTK-build/bin/designer/Release/CTK??????WidgetsPlugins.{so|dll}''
* ''Slicer-Superbuild/Slicer-build/bin/designer/Release/qSlicer??????WidgetsPlugins.{so|dll}''
* ''Slicer-Superbuild/Slicer-build/bin/iconengines/Release/qSlicer??????Plugin.{so|dll}''

See [[Documentation/{{documentation/version}}/Developers/DirectoryStructure#Build_tree|Build directory structure]]

== Install ==
<code>QT_PLUGIN_PATH</code> points to a unique path: <code>Slicer_INSTALL_QtPlugins_DIR</code>=''Slicer/lib/QtPlugins''. However, on MacOSX, there is no launcher, so environment variables can't be set prior to launching Slicer. A ''qt.conf'' containing the ''Slicer/lib/QtPlugins'' path is used for the mac bundle.
In order for the plugins to be installed at the right location, <code>CTK_INSTALL_QTPLUGIN_DIR</code> must be passed to CTK (see [http://viewvc.slicer.org/viewvc.cgi/Slicer4/trunk/SuperBuild/External_CTK.cmake?view=markup External_CTK.cmake], this is internally used by ''ctkMacroBuildQtPlugin.cmake'')
Because Qt is packaged within Slicer, the plugins must also be packaged (see [http://viewvc.slicer.org/viewvc.cgi/Slicer4/trunk/CMake/SlicerBlockInstallQtPlugins.cmake?view=markup SlicerBlockInstallQtPlugins.cmake])
Plugins locations for installed Slicer:
* Slicer/lib/QtPlugins/designer/CTK??????WidgetsPlugins.{so|dll}
* Slicer/lib/QtPlugins/iconengines/qSlicer??????WidgetsPlugins.{so|dll}
* Slicer/lib/QtPlugins/imageformats/*.{so|dll|dylib}
* Slicer/lib/QtPlugins/sqldrivers/*.{so|dll|dylib}

See [[Documentation/{{documentation/version}}/Developers/DirectoryStructure#Install_tree|Install directory structure]]

== Extensions ==
Extensions need to provide their plugin paths to the Slicer launcher.
{{documentation/underconstruction}}

Documentation/4.5/Developers/QtPlugins - Revision history

UpdateBot: Nightly -> 4.5