How to create a new MITK Module

Create a Folder for your Module

First, create a folder for your module within /Modules e.g. 'NewModule'. You need to add the new Folder to the CMakeLists.txt in the Module directory as well as well. Open /Modules/CMakeLists.txt, insert it into the set(module_dirs) section.

set(module_dirs
    ...
    NewModule
)

A simple example module is provided in the MITK/Examples/FirstSteps/NewModule directory, it includes a new data type (more information at How to create a new custom data type) and adds a MiniApp for that data type (more information at How to create a MiniApp command line tool).

Within the module we recommend using a Unix like directory structure. This helps others finding their way around your code. Depending on your use case you might not need every directory.

NewModule/
  autoload/
  cmdapps/
  doc/
  include/
  resource/
  src/
  test/

Subsequently a quick description of what each directory contains.

autoload

This directory should not directly contain files. Instead it contains further directories each of which is its own module.

These modules provide functionality which should be available at application start, but will not be included by other modules. Examples would be a module registering readers/writers or providing an interface for specific hardware.

For an example of an autoload module take a look at NewModule/autoload/IO.

cmdapps

This directory contains all cmdapps (command line tools) related to your module. For more information see How to create a MiniApp command line tool.

doc

This directory contains the documentation for your module.

include

This directory contains all header files which might be included by other modules.

resource

This directory contains resources needed by your module, such as xmls, images or similar.

src

This directory contains source and header files which should not be included by other modules. Further subdivision can help keeping it organized. (e.g. src/DataManagement src/Algorithms)

test

This directory contains all tests for your module.

Create CMakeLists.txt

Within your module create a CMakeLists.txt using the MITK_CREATE_MODULE macro:

An example:

MITK_CREATE_MODULE(
  INCLUDE_DIRS
    PUBLIC ${MITK_BINARY_DIR}
    PRIVATE src/DataManagement
  DEPENDS PUBLIC MitkCore
  WARNINGS_AS_ERRORS
  SUBPROJECTS MITK-Examples
)

add_subdirectory(autoload/IO)
add_subdirectory(cmdapps)
add_subdirectory(test)

If you do not choose a module name, one will be generated based on the folder name (In this case the resulting name will be MitkNewModule). This name has to be unique across the entire project in order to avoid collisions. It should only contain Letters (both upper- and lowercase), no numbers, no underscores etc.

An example of an autoload module that sets its own name is:

MITK_CREATE_MODULE( NewModuleIO
  INCLUDE_DIRS
    PRIVATE src/IO
  DEPENDS PUBLIC MitkNewModule MitkSceneSerialization
  PACKAGE_DEPENDS
    PRIVATE tinyxml
  AUTOLOAD_WITH MitkCore
  WARNINGS_AS_ERRORS
  SUBPROJECTS MITK-Examples
)

the resulting name is MitkNewModuleIO.

Note

For more information about the parameters of the new module macro see mitkFunctionCreateModule.cmake

Create files.cmake

Next, create a new file and name it files.cmake, containing the files of your module.

An example:

set(CPP_FILES
  mitkExampleDataStructureReaderService.cpp
  mitkExampleDataStructureReaderService.h
  mitkExampleDataStructureSerializer.cpp
  mitkExampleDataStructureSerializer.h
  mitkExampleDataStructureWriterService.cpp
  mitkExampleDataStructureWriterService.h
  mitkExampleIOMimeTypes.cpp
  mitkExampleIOMimeTypes.h
  mitkNewModuleIOActivator.cpp
)

If you do not add a source file here it will not be compiled, unless it is included elsewhere.

Set up the Test environment

Providing tests for your code is a very good way to save yourself a lot of debugging time and ensure consistency. An example of a small test environment is provided in the NewModule example.

Again you need a CMakeLists.txt, e.g.:

MITK_CREATE_MODULE_TESTS()

a files.cmake, e.g.:

set(MODULE_TESTS
  mitkExampleDataStructureReaderWriterTest.cpp
  mitkExampleDataStructureTest.cpp
)

SET(MODULE_CUSTOM_TESTS
)

and an actual test, e.g.:

/*===================================================================

The Medical Imaging Interaction Toolkit (MITK)

Copyright (c) German Cancer Research Center,
Division of Medical and Biological Informatics.
All rights reserved.

This software is distributed WITHOUT ANY WARRANTY; without
even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE.

See LICENSE.txt or http://www.mitk.org for details.

===================================================================*/

// Testing
#include "mitkTestFixture.h"
#include "mitkTestingMacros.h"

// std includes
#include <string>

// MITK includes
#include "mitkExampleDataStructure.h"

// VTK includes
#include <vtkDebugLeaks.h>

class mitkExampleDataStructureTestSuite : public mitk::TestFixture
{
  CPPUNIT_TEST_SUITE(mitkExampleDataStructureTestSuite);

  // Test the append method
  MITK_TEST(Append_ExampleString_AddsExampleStringToData);
  CPPUNIT_TEST_SUITE_END();

private:
  mitk::ExampleDataStructure::Pointer m_Data;
  std::string m_DefaultDataString;

public:
  void setUp() override
  {
    m_DefaultDataString = "This is the example data content\nAnd a second line\n";
    m_Data = mitk::ExampleDataStructure::New();
    m_Data->SetData(m_DefaultDataString);
  }

  void tearDown() override
  {
    m_DefaultDataString = "";
    m_Data = nullptr;
  }

  void Append_ExampleString_AddsExampleStringToData()
  {
    std::string appendedString = "And a third line\n";
    std::string wholeString = m_DefaultDataString + appendedString;
    m_Data->AppendAString(appendedString);

    CPPUNIT_ASSERT_MESSAGE("Checking whether string was correctly appended.", m_Data->GetData() == wholeString);
  }
};

MITK_TEST_SUITE_REGISTRATION(mitkExampleDataStructure)

For more information regarding tests please refer to Testing.

That's it! Enjoy your new module!