KDevelop5/Project template specification

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    File structure

    A project template is a compressed archives with specific contents. Every template needs a description file with the same base name as the archive itself, and an extension .kdevtemplate. Optionally there can also be an image file which will be used as preview or symbolic display with the description (preferred size: 200 pixels width). Other files are treated as template contents and will be present in the generated project.

    The directory structure within the archive can be similar to this

    my_template.tar.bz2
    +-- my_template.kdevtemplate
    +-- my_template.png
    |-- src/
    |   |-- CMakeLists.txt
    |   |-- main.cpp
    |   |-- %{APPNAMELC}.h
    |   +-- %{APPNAMELC}.cpp
    +-- CMakeLists.txt
    +-- %{PROJECTDIRNAME}.kdev4
    

    Let's say we create the project using the above template and application name Example. The resulting project tree will look like this

    ~/projects/Example
    |-- src/
    |   |-- CMakeLists.txt
    |   |-- main.cpp
    |   |-- example.h
    |   +-- example.cpp
    +-- CMakeLists.txt
    +-- Example.kdev4
    

    The .kdevtemplate description file was removed, as it is used to describe the template, not the resulting project. The same was done to the file my_template.png (which is referred to from the description file). Other files have been copied from the archive to the project folder. Variables in files names have been replaced with their values. Although not visible from the file structure, variables in the files' contents have been replaced as well.

    Variables

    Project templates in KDevelop, just like in KAppTemplate, use KMacroExpander to substitute variable placeholders with their real values. This means that when generating a project, strings of the form %{VARIABLE_NAME} will be replaced with the value of VARIABLE_NAME.

    The recognized variables in KDevelop are

    Variable name Description Example value
    APPNAME The application name, specified when starting a project Example
    APPNAMELC The application name in lowercase example
    APPNAMEUC The application name in uppercase EXAMPLE
    APPNAMEID The application name with all non-alphanumeric characters replaced with undescores. Useful for identifiers. Example
    PROJECTDIR Absolute path to the directory where the project is being created /home/<user>/projects/Example
    PROJECTDIRNAME The name of the directory where the project is being created Example
    VERSIONCONTROLPLUGIN The version control plugin, chosen in the assistant dialog kdevgit, kdevsvn, kdevcvs, or empty of no version control was selected

    Description file structure

    Template description files, with the extension of .kdevtemplate, follow the freedesktop.org desktop file specification. They are quite simple, with a single category, and three required entries (Name, Comment, Category) and two optional (ShowFilesAfterGeneration, Icon).

    Here is an example template description file:

    [General]
    Name=Simple C++ application
    Comment=An example C++ application, showing the features of templates for project generation. 
    Icon=SimpleApp.png
    ShowFilesAfterGeneration=src/%{APPNAMELC}.cpp
    Category=Qt/Examples
    

    The Name and Comment entries can be translated, like they are in all .desktop files, by appending locale-specific identifier to the keys. The other three entries are read by KDevelop and are used mainly for user convenience. The entry Category serves to better divide templates in a tree view for selection. It can contain any number of levels, separated by slashes, but it is recommended to always use two levers for consistency. If a ShowFilesAfterGeneration entry is present, the specified files are opened after the project is created. If an Icon entry is present, the specified file will be used as preview image and not copied into the generated sources.

    CMake macro

    Keeping source code in compressed archives is an inconvenience, both for version control systems and for users when trying to edit these templates. For that reason, KDevPlatform includes a convenience CMake macro that compresses and installs a directory as a template archive.

    For instance, a number of templates can be kept in a directory structure such as this

    templates/
    |-- example/
    |   |-- basic_cpp_example/
    |   |   |-- basic_cpp_example.kdevtemplate
    |   |   +-- other files
    |   +-- kde_cpp_example/
    |       |-- kde_cpp_example.kdevtemplate
    |       +-- other files
    |-- CMakeLists.txt
    

    These templates can be compressed with the following CMake commands

    set(example_template_DIRS
        example/basic_cpp_example
        example/kde_cpp_example
    )
    
    kdevplatform_add_app_templates(${example_template_DIRS})
    

    Note that kdevplatform_add_app_templates also adds the templates to the list of install targets, so you do not have to install them yourself. They are installed into a directory where KDevelop will detect and load them.

    Using the templates

    Instructions for starting a new project from a template are avaliable in the Userbase section Setting up a new project. If you installed the template using a CMake script, it will be picked up by KDevelop immediately when you (re-)open the "Create New Project" dialog.