View source for Documentation/4.5/Developers/Tutorials/CreateLoadableModule

<noinclude>{{documentation/versioncheck}}</noinclude>
=Consider also reading=
*[[Media:QtPortInSlicer.ppt|QtPortInSlicer - How to write a module]]
*[[Documentation/{{documentation/version}}/Developers/Tutorials/ExternalModuleWriting|How to write an external module]]

= Initialization =
=== 1) Create the module directory ===

Use the [[Documentation/{{documentation/version}}/Developers/ExtensionWizard|extension wizard]] to generate files and directory based on a template.

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Start terminal (<code>bash</code> or <code>Terminal.app</code>), then type the following:<br>
 $ cd /path/to/Slicer4
 $ python Utilities/Scripts/ModuleWizard.py MY_MODULE_NAME
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Start <code>cmd.exe</code> terminal, then type the following (in 64-bit mode replace <code>PCbuild</code> with <code>PCbuild\amd64</code>):<br>
 $ cd C:\path\to\Slicer4
 $ ..\Slicer4-Superbuild\python-build\PCBuild\python.exe Utilities\Scripts\ModuleWizard.py MY_MODULE_NAME
|}
Replace <code>MY_MODULE_NAME</code> with the name of the module you want (e.g. <code>HelloWorld</code>)<br>
After running the script, a new directory <code>MY_MODULE_NAME</code> will be created in <code>Slicer4/Modules/Loadable</code>
<br><br>
-->

=== 2) Build ===

See [[Documentation/Nightly/Developers/ExtensionWizard#Building]]


=== 3) Install ===

See [[Documentation/Nightly/Developers/ExtensionWizard#.22Installation.22]]

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=== 2) Add the module in CMake ===
Edit the file [http://viewvc.slicer.org/viewvc.cgi/Slicer4/trunk/Modules/Loadable/CMakeLists.txt?view=markup Slicer4/Modules/Loadable/CMakeLists.txt]:
Add the name of your module at the end of the qtmodules variable assignment:
 ...
 set(qtmodules
   ...
   MY_MODULE_NAME
   )
 ...
<br><br>
=== 3) Compile ===
Compile the inner build (''Slicer-build'' inside the Superbuild directory).
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 $ cd ../Slicer4-Superbuild/Slicer-build;
 $ make -j4
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 $ cd ..\Slicer4-Superbuild\Slicer-build;
 $ .\Slicer.exe --VisualStudio Slicer.sln
In Visual Studio, go to Build -> Build Solution
|}
<br><br>
-->

=== 4) Check the module ===
Start Slicer and make sure the module is present (listed under "Module Template")
 $ ./Slicer
To change the module title that shows up in Slicer, edit the file <code>Slicer4/Modules/Loadable/MY_MODULE_NAME/CMakeLists.txt</code> 
 set(MODULE_TITLE "Your title") 
Other [http://slicer.org/doc/html/classqSlicerAbstractCoreModule.html#properties properties] for the module such as '''help''', '''acknowledgment''' or '''categories''' can be re-implemented directly in C++ by editing <code>Slicer4/Modules/Loadable/MY_MODULE_NAME/qSlicerMY_MODULE_NAME.cxx</code>. 
<br><br>

=== 5) Open Qt Designer using the launcher ===
''Slicer'' (the launcher) searches Qt Designer on your machine (using <code>QT_QMAKE_EXECUTABLE</code> set at configure time). It starts the designer after setting the correct environment variables (<code>QT_PLUGIN_PATH</code> for the widgets designer plugins and PATH/LD_LIBRARY_PATH for the libraries).
 $ ./Slicer --designer
<br><br>

=== 6) Change the UI ===
Using Qt Designer, edit the module UI file: <code>Modules/Loadable/MY_MODULE_NAME/Resources/UI/qSlicerMY_MODULE_NAMEModule.ui</code><br>
[[Documentation/{{documentation/version}}/Developers/Tutorials/QtDesigner|More info on how to use the designer]]
<br><br>

=== 7) Edit the module files ===
 Slicer4/Modules/Loadable/MY_MODULE_NAME/qSlicerMY_MODULE_NAME.[h|cxx]
 Slicer4/Modules/Loadable/MY_MODULE_NAME/qSlicerMY_MODULE_NAMEWidget.[h|cxx]
 Slicer4/Modules/Loadable/MY_MODULE_NAME/Logic/vtkSlicerMY_MODULE_NAMELogic.[h|cxx]
 ...
<br><br>

= Qt Designer =
* How to set icons to widgets
** In the icon property entry of the widget (Property Editor), select a resource file
*** Slicer4/Modules/Loadable/MY_MODULE_NAME/Resources/qSlicerMY_MODULE_NAMEModule.qrc
*** Slicer4/Libs/MRML/Widgets/Resources/qMRMLWidget.qrc
*** Slicer4/Base/QTGUI/Resources/qSlicerBaseQTGUI.qrc
* How to add an icon in a resource file
** Add the icon in Slicer4/Modules/Loadable/MY_MODULE_NAME/Resources/Icon
** Edit the resource file by adding the line
*** "<file>Icons/MyIcon.png</file>"

= Dependency between modules =
It is possible that your module needs to access information from another module. Typically the logic or the custom MRML classes of a module.
The following code is an example of what can be done to make your module dependent to the Volumes module logic:

In CMakeLists.txt:
  set(MODULE_INCLUDE_DIRECTORIES
    ${CMAKE_CURRENT_SOURCE_DIR}/Widgets
    ${CMAKE_CURRENT_BINARY_DIR}/Widgets
    ${vtkSlicerVolumesModuleLogic_SOURCE_DIR}
    ${vtkSlicerVolumesModuleLogic_BINARY_DIR}
    )
   ... 
  set(MODULE_TARGET_LIBRARIES
    ...
    vtkSlicerVolumesModuleLogic
    )

In qSlicerMY_MODULE_NAMEModule.cxx:
  
  //-----------------------------------------------------------------------------
  QStringList qSlicerMY_MODULE_NAMEModule::dependencies()const
  {
    return QStringList() << "Volumes";
  }
  
  //-----------------------------------------------------------------------------
  void qSlicerMY_MODULE_NAMEModule::setup()
  {
    this->Superclass::setup();
 
    vtkSlicerMY_MODULE_NAMELogic* moduleLogic =
      vtkSlicerMY_MODULE_NAMELogic::SafeDownCast(this->logic());
 
    qSlicerAbstractCoreModule* volumesModule =
      qSlicerCoreApplication::application()->moduleManager()->module("Volumes");
    if (volumesModule)
      {
      vtkSlicerVolumesLogic* volumesLogic = 
        vtkSlicerVolumesLogic::SafeDownCast(volumesModule->logic());
      moduleLogic->SetVolumesLogic(volumesLogic);
      }

By specifying the module as a dependency, you are insured that the dependency module will be setup before your module is setup.

Follow the same pattern in CMakeLists.txt to add dependency on a module widgets:

 set(MODULE_INCLUDE_DIRECTORIES
   ... 
   ${qSlicerVolumesModuleWidgets_SOURCE_DIR}
   ${qSlicerVolumesModuleWidgets_BINARY_DIR}
   ...
   )
  ...
  set(MODULE_TARGET_LIBRARIES
    ...
    qSlicerVolumesModuleWidgets
    )

It works the same if you want to access the custom MRML (''vtkSlicerDEPENDENT_MODULEModuleMRML_SOURCE_DIR'') or displayable manager (''vtkSlicerDEPENDENT_MODULEModuleDisplayableManager_SOURCE_DIR'') classes.

== Examples ==
# [[Documentation/{{documentation/version}}/Modules/CropVolume|Crop Volume]] module [http://viewvc.slicer.org/viewvc.cgi/Slicer4/trunk/Modules/Loadable/CropVolume/qSlicerCropVolumeModule.cxx?view=markup depends] on [[Documentation/{{documentation/version}}/Modules/Volumes|Volumes]] module