Development/Tutorials/Plasma4/PackageStructure: Difference between revisions

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    ==Abstract==
    A Plasma Package is a set of files, usually shipped in a single compressed archive, that together provide one particular data or functionality addon, such as Plasmoid or a Wallpaper set. Packages may be defined for any kind of custom data (e.g. non-compiled) addons. Packages can be installed, removed, listed and updated.
    A Plasma Package is a set of files, usually shipped in a single compressed archive, that together provide one particular data or functionality addon, such as Plasmoid or a Wallpaper set. Packages may be defined for any kind of custom data (e.g. non-compiled) addons. Packages can be installed, removed, listed and updated.


    Line 6: Line 5:
    ==plasmapkg==
    ==plasmapkg==
    The plasmapkg command line tool is used to get information about Packages and install, remove or upgrade them. Run  
    The plasmapkg command line tool is used to get information about Packages and install, remove or upgrade them. Run  
    <code bash>
    <syntaxhighlight lang="bash">
    plasmapkg --help
    plasmapkg --help
    </code>
    </syntaxhighlight>
    to get a list of available options. The most commonly used options are  
    to get a list of available options. The most commonly used options are  
    {{path|-i}} for installing and {{path|-r}} for removing a package.
    {{path|-i}} for installing and {{path|-r}} for removing a package.
    Line 16: Line 15:
    Every PackageStructure needs a desktop file to tell plasma what package it's defining:
    Every PackageStructure needs a desktop file to tell plasma what package it's defining:
    '''plasma-packagestructure-test.desktop'''
    '''plasma-packagestructure-test.desktop'''
    <code ini>
    <syntaxhighlight lang="ini">
    [Desktop Entry]
    [Desktop Entry]
    Name=Test
    Name=Test
    Line 34: Line 33:
    X-Plasma-PackageFileFilter=*.test
    X-Plasma-PackageFileFilter=*.test
    X-Plasma-PackageFileMimetypes=application/zip
    X-Plasma-PackageFileMimetypes=application/zip
    </code>
    </syntaxhighlight>
    The most important fields are:
    The most important fields are:
    * Name, Comment and Type fields, which are required for all desktop files.
    * Name, Comment and Type fields, which are required for all desktop files.
    Line 44: Line 43:
    ===The Header File===
    ===The Header File===
    '''testpackage.h'''
    '''testpackage.h'''
    <code cppqt>
    <syntaxhighlight lang="cpp-qt">
    #ifndef TESTPACKAGESTRUCTURE_H
    #ifndef TESTPACKAGESTRUCTURE_H
    #define TESTPACKAGESTRUCTURE_H
    #define TESTPACKAGESTRUCTURE_H
    Line 64: Line 63:
    // This declares the plugin so it can be loaded at runtime from its shared library.
    // This declares the plugin so it can be loaded at runtime from its shared library.
    // The class name is used as the second parameters.
    // The class name is used as the second parameters.
    K_EXPORT_PLASMA_PACKAGESTRUCTURE(test, TestPackageStructure)
    K_EXPORT_PLASMA_PACKAGESTRUCTURE(myproject_test, TestPackageStructure)
    #endif // TESTPACKAGE_H
    #endif // TESTPACKAGE_H
    </code>
    </syntaxhighlight>


    ===The Main Code===
    ===The Main Code===
    '''testpackage.cpp'''
    '''testpackage.cpp'''
    <code cppqt>
    <syntaxhighlight lang="cpp-qt">
    #include "testpackage.h"
    #include "testpackage.h"


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         Q_UNUSED(args)
         Q_UNUSED(args)
         // tell plasma about your package's directory structure with addDirectoryDefinition
         // tell plasma about your package's directory structure with addDirectoryDefinition
         addDirectoryDefinition("images", QLatin1String("images"), i18n( Images") );
         addDirectoryDefinition("images", QLatin1String("images"), i18n("Images") );
         // what does the directory contain?
         // what does the directory contain?
         QStringList mimetypes;
         QStringList mimetypes;
    Line 108: Line 107:
         setServicePrefix(QLatin1String("plasma-test-"));
         setServicePrefix(QLatin1String("plasma-test-"));
    }
    }
    </code>
    </syntaxhighlight>


    ====Dynamic File Definition====
    ====Dynamic File Definition====
    For simplicity's sake, in this Example we've added code/main.js as the only file definition for the primary script file. With this approach, the package will only js scripts. If you want to support a larger set of scripting languages or allow the main script file to be defined within the package's metadata file, then the PackageStructure subclass should reimpliment the protect virtual method pathChanged, which is called whenever the path this PackageStructure is representing changes (including when first set), and set the extension of the script file, perhaps using code like this:
    For simplicity's sake, in this Example we've added code/main.js as the only file definition for the primary script file. With this approach, the package will only js scripts. If you want to support a larger set of scripting languages or allow the main script file to be defined within the package's metadata file, then the PackageStructure subclass should reimplement the protect virtual method pathChanged, which is called whenever the path this PackageStructure is representing changes (including when first set), and set the extension of the script file, perhaps using code like this:
    <code cppqt>
    <syntaxhighlight lang="cpp-qt">
    // get path to your installed packages
    // get path to your installed packages
    void TestPackageStructure::pathChanged()
    void TestPackageStructure::pathChanged()
    Line 144: Line 143:
         }
         }
    }
    }
    </code>
    </syntaxhighlight>


    ==Build and Install==
    ==Build and Install==
    the CMakeLists.txt file tells cmake how to build and install your project, add the following lines to this file to for this test project:
    the CMakeLists.txt file tells CMake how to build and install your project, add the following lines to this file to for this test project. Note that the name used in kde4_add_plugin must match the library name used in the .desktop file:
    <code bash>
    <syntaxhighlight lang="cmake">
    set(testpackage_SRC testpackage.cpp)
    set(testpackage_SRC testpackage.cpp)


    kde4_add_plugin( plasma-packagestructure-test ${testpackage_SRC} )
    kde4_add_plugin(plasma_packagestructure_myproject_test ${testpackage_SRC} )
    target_link_libraries( plasma-packagestructure-test ${KDE4_KDEUI_LIBS} ${KDE4_PLASMA_LIBS} )
    target_link_libraries(plasma_packagestructure_myproject_test ${KDE4_KDEUI_LIBS} ${KDE4_PLASMA_LIBS})
    install( TARGETS plasma-packagestructure-test DESTINATION ${PLUGIN_INSTALL_DIR} )
    install(TARGETS plasma_packagestructure_myproject_test DESTINATION ${PLUGIN_INSTALL_DIR})
    install( FILES plasma-packagestructure-test.desktop DESTINATION ${SERVICES_INSTALL_DIR} )
    install(FILES plasma-packagestructure-myproject-test.desktop DESTINATION ${SERVICES_INSTALL_DIR})
    </code>
    </syntaxhighlight>

    Revision as of 10:20, 30 June 2011

    A Plasma Package is a set of files, usually shipped in a single compressed archive, that together provide one particular data or functionality addon, such as Plasmoid or a Wallpaper set. Packages may be defined for any kind of custom data (e.g. non-compiled) addons. Packages can be installed, removed, listed and updated.

    Plasma::PackageStructure defines what is in a Package. This information is used to create packages and provides a way to programmatically refer to the contents. It's also used to provide an installation profile for your Packages.

    plasmapkg

    The plasmapkg command line tool is used to get information about Packages and install, remove or upgrade them. Run

    plasmapkg --help
    

    to get a list of available options. The most commonly used options are -i for installing and -r for removing a package.

    The Code

    The Desktop File

    Every PackageStructure needs a desktop file to tell plasma what package it's defining: plasma-packagestructure-test.desktop

    [Desktop Entry]
    Name=Test
    Comment=Test Package Structure
    Type=Service
    
    X-KDE-ServiceTypes=Plasma/PackageStructure
    X-KDE-Library=plasma_packagestructure_myproject_test
    
    X-KDE-PluginInfo-Author=Farhad Hedayati Fard
    X-KDE-PluginInfo-Email=[email protected]
    X-KDE-PluginInfo-Name=MyProject/Test
    X-KDE-PluginInfo-Version=0.1
    X-KDE-PluginInfo-Website=http://plasma.kde.org/
    X-KDE-PluginInfo-License=GPLv3+
    X-KDE-PluginInfo-EnabledByDefault=true
    X-Plasma-PackageFileFilter=*.test
    X-Plasma-PackageFileMimetypes=application/zip
    

    The most important fields are:

    • Name, Comment and Type fields, which are required for all desktop files.
    • X-KDE-ServiceTypes field which tells plasma that this is a PackageStructure
    • X-KDE-PluginInfo-Name field which should be identical to the name used in your code (discussed later). This name must also be globally unique to all other PackageStructure plugins, and so using a name that includes unique components such as your project or organization's name is recommended to avoid naming collisions with other plugins.
    • X-KDE-Library field which tells plasma how to load/install the packages with this package structure.
    • X-KDE-PluginInfo-Name field which should be identical to the name of dataengine/plasmoid that uses this PackageStructure.

    The Header File

    testpackage.h

    #ifndef TESTPACKAGESTRUCTURE_H
    #define TESTPACKAGESTRUCTURE_H
    
    // We need this header since we are inheriting it
    #include <plasma/packagestructure.h>
    
    /**
     This PackageStructure provides an structure for packages used by the test 
     DataEngine.
    */
    class TestPackageStructure : public Plasma::PackageStructure
    {
    public:
      // Every PackageStructure needs an explicit constructor with these arguments 
      explicit TestPackageStructure(QObject *parent = 0, const QVariantList& args = QVariantList());
    };
    
    // This declares the plugin so it can be loaded at runtime from its shared library.
    // The class name is used as the second parameters.
    K_EXPORT_PLASMA_PACKAGESTRUCTURE(myproject_test, TestPackageStructure)
    #endif // TESTPACKAGE_H
    

    The Main Code

    testpackage.cpp

    #include "testpackage.h"
    
    #include "plasma/applet.h"
    #include "plasma/package.h"
    
    /**
     We pass Plasma/Test as the type to the Plasma::PackageStructure. this string
     should be identical to the "X-KDE-PluginInfo-Name" in the desktop file,
     otherwise plasmapkg won't recognize your package and you'll get an this error
     when trying to install your packages:
     Could not find a suitable installer for package of type Plasma/Test
    */
    TestPackageStructure::TestPackageStructure(QObject *parent, const QVariantList& args)
        : Plasma::PackageStructure(parent, QLatin1String("MyProject/Test"))
    {
        Q_UNUSED(args)
        // tell plasma about your package's directory structure with addDirectoryDefinition
        addDirectoryDefinition("images", QLatin1String("images"), i18n("Images") );
        // what does the directory contain?
        QStringList mimetypes;
        mimetypes << QLatin1String("image/svg+xml") << QLatin1String("image/png") << QLatin1String("image/jpeg");
        setMimetypes("images", mimetypes);
    
        addDirectoryDefinition("scripts", QLatin1String("code"), i18n("Executable Scripts"));
        mimetypes.clear();
        mimetypes << QLatin1String("text/*");
        setMimetypes("scripts", mimetypes);
        // tell plasma what is the name of script in the package.
        addFileDefinition("mainscript", QLatin1String("code/main.js"), i18n("Main Script File"));
    
        // tell plasma where to install your package.
        // normally this would be prepended with ~/.kde4/share/apps/
        // so the final path to your package after installation is ~/.kde4/share/apps/plasma/test/
        setDefaultPackageRoot(QLatin1String("plasma/test/"));
        // You'll need to use this service prefix when you want to access "test" packages.
        setServicePrefix(QLatin1String("plasma-test-"));
    }
    

    Dynamic File Definition

    For simplicity's sake, in this Example we've added code/main.js as the only file definition for the primary script file. With this approach, the package will only js scripts. If you want to support a larger set of scripting languages or allow the main script file to be defined within the package's metadata file, then the PackageStructure subclass should reimplement the protect virtual method pathChanged, which is called whenever the path this PackageStructure is representing changes (including when first set), and set the extension of the script file, perhaps using code like this:

    // get path to your installed packages
    void TestPackageStructure::pathChanged()
    {
        if (path().isEmpty()) {
            return;
        }
     
        // Check if the Package developer was kind enough to tell us
        // what script to use as the main script
        KDesktopFile config(path() + "/metadata.desktop");
        KConfigGroup cg = config.desktopGroup();
        QString mainScript = cg.readEntry("X-Plasma-MainScript", QString());
        if (!mainScript.isEmpty()) {
            addFileDefinition("mainscript", mainScript, i18n("Main Script File"));
            setRequired("mainscript", true);
            return;
        }
    
        // get mainscript's file path (now code/main - without file extension)
        const QString mainscript = path() + "contents/code/main";
        
       // iterate through supported scripting bindings.
       // you can learn how to retrieve such a list in Kross tutorials.
       foreach (const QString &extention, supportedScriptLangs()) {
            if (QFile::exists(mainscript + extension)) {
                addFileDefinition("mainscript", mainScript + extension, i18n("Main Script File"));
                setRequired("mainscript", true);
                return;
            }
        }
    }
    

    Build and Install

    the CMakeLists.txt file tells CMake how to build and install your project, add the following lines to this file to for this test project. Note that the name used in kde4_add_plugin must match the library name used in the .desktop file:

    set(testpackage_SRC testpackage.cpp)
    
    kde4_add_plugin(plasma_packagestructure_myproject_test ${testpackage_SRC} )
    target_link_libraries(plasma_packagestructure_myproject_test ${KDE4_KDEUI_LIBS} ${KDE4_PLASMA_LIBS})
    install(TARGETS plasma_packagestructure_myproject_test DESTINATION ${PLUGIN_INSTALL_DIR})
    install(FILES plasma-packagestructure-myproject-test.desktop DESTINATION ${SERVICES_INSTALL_DIR})