Development/Tutorials/First program/pt-br: Difference between revisions

    From KDE TechBase
    (Updating to match new version of source page)
    (Updating to match new version of source page)
    Line 8: Line 8:
    name=Hello World|
    name=Hello World|


    pre=[http://mindview.net/Books/TICPP/ThinkingInCPP2e.html C++], [http://qt.nokia.com Qt], [[Getting_Started/Build|Building KDE]]|
    pre=[http://mindview.net/Books/TICPP/ThinkingInCPP2e.html C++], [https://www.qt.io/ Qt], [[Special:myLanguage/Getting_Started/Build|Building KDE]]|


    next=[[Development/Tutorials/Using_KXmlGuiWindow|Tutorial 2 - KXmlGuiWindow]]|  
    next=[[Special:myLanguage/Development/Tutorials/Using_KXmlGuiWindow|Tutorial 2 - KXmlGuiWindow]]|  


    reading=[[Development/Tutorials/CMake|CMake]]
    reading=[[Special:myLanguage/Development/Tutorials/CMake|CMake]]
    }}
    }}


    ==Resumo==
    ==Resumo==


    Seu primeiro programa deve cumprimentar o mundo com um simpático "Hello World". Para isso, nós usaremos uma classe {{class|KMessageBox}} e personalizar um dos botões.
    Your first program shall greet the world with a friendly "Hello World", what else? For that, we will use a {{class|KMessageBox}} and customise one of the buttons.
    [[image:introtokdetutorial1.png|frame|center]]


    [[image:Introtokdetutorial1-kf5.png|frame|center]]
    [[image:Introtokdetutorial1-kf5.png|frame|center]]
    Line 25: Line 24:


    {{Tip|
    {{Tip|
    Você pode querer usar [[qtcreator|QtCreator]] como IDE para seus projetos.
    You might want to use [[Special:myLanguage/KDevelop|KDevelop]] or [[Special:myLanguage/qtcreator|QtCreator]] as IDE for your projects.
    }}
    }}


    ==O código==
    ==O código==


    Todo o código que precisamos estará em um arquivo, <tt>main.cpp</tt>. Crie esse arquivo com o código abaixo:
    All the code we need will be in one file, <tt>main.cpp</tt>. Create that file with the code below:
    <syntaxhighlight lang="cpp-qt">
    #include <cstdlib>
     


    <syntaxhighlight lang="cpp-qt">
    <syntaxhighlight lang="cpp-qt">
    #include <cstdlib>
    #include <cstdlib>


     
    #include <QApplication>
    <!--{-->KCmdLineArgs::init( argc, argv, &aboutData );
    #include <QCommandLineParser>
        KApplication app;
    #include <KAboutData>
        KGuiItem yesButton( i18n( "Hello" ), QString(),
    #include <KLocalizedString>
                            i18n( "This is a tooltip" ),
    #include <KMessageBox>
                            i18n( "This is a WhatsThis help text." ) );
        return
            KMessageBox ::questionYesNo
            (0, i18n( "Hello World" ), i18n( "Hello" ), yesButton )
            == KMessageBox ::Yes? EXIT_SUCCESS: EXIT_FAILURE;
    }
    </syntaxhighlight>
    O primeiro código específico do KDE que nós encontramos nesse programa é {{class|KAboutData}}. Essa é a classe usada para armazenar informações sobre o programa tais como uma breve descrição, autores ou informações sobre a licença.
    Praticamente todas as aplicações KDE devem usar esta classe.


    int main (int argc, char *argv[])
    int main (int argc, char *argv[])
    {
    {
        QApplication app(argc, argv);
        KLocalizedString::setApplicationDomain("tutorial1");
       
         KAboutData aboutData(
         KAboutData aboutData(
                             // The program name used internally.
                             // The program name used internally. (componentName)
                             "tutorial1",
                             QStringLiteral("tutorial1"),
                            // The message catalog name
                             // A displayable program name string. (displayName)
                            // If null, program name is used instead.
                             i18n("Tutorial 1"),
                            0,
                             // The program version string. (version)
                             // A displayable program name string.
                             QStringLiteral("1.0"),
                             ki18n("Tutorial 1"),
                             // Short description of what the app does. (shortDescription)
                             // The program version string.
                             i18n("Displays a KMessageBox popup"),
                             "1.0",
                             // Short description of what the app does.
                             ki18n("Displays a KMessageBox popup"),
                             // The license this code is released under
                             // The license this code is released under
                             KAboutData::License_GPL,
                             KAboutLicense::GPL,
                             // Copyright Statement
                             // Copyright Statement (copyrightStatement = QString())
                             ki18n("(c) 2007"),
                             i18n("(c) 2015"),
                             // Optional text shown in the About box.
                             // Optional text shown in the About box.
                             // Can contain any information desired.
                             // Can contain any information desired. (otherText)
                             ki18n("Some text..."),
                             i18n("Some text..."),
                             // The program homepage string.
                             // The program homepage string. (homePageAddress = QString())
                             "http://example.com/",
                             QStringLiteral("http://example.com/"),
                             // The bug report email address
                             // The bug report email address
                             "[email protected]");
                             // (bugsEmailAddress = QLatin1String("[email protected]")
    <!--}-->
                            QStringLiteral("[email protected]"));
        aboutData.addAuthor(i18n("Name"), i18n("Task"), QStringLiteral("[email protected]"),
                            QStringLiteral("http://your.website.com"), QStringLiteral("OSC Username"));
        KAboutData::setApplicationData(aboutData);


         QCommandLineParser parser;
         QCommandLineParser parser;
        parser.addHelpOption();
        parser.addVersionOption();
         aboutData.setupCommandLine(&parser);
         aboutData.setupCommandLine(&parser);
         parser.process(app);
         parser.process(app);
    Line 91: Line 80:
                             i18n( "This is a WhatsThis help text." ) );
                             i18n( "This is a WhatsThis help text." ) );


        return  
    return  
             KMessageBox::questionYesNo  
             KMessageBox::questionYesNo  
             (0, i18n( "Hello World" ), i18n( "Hello" ), yesButton )  
             (0, i18n( "Hello World" ), i18n( "Hello" ), yesButton )  
             == KMessageBox::Yes? EXIT_SUCCESS: EXIT_FAILURE;
             == KMessageBox::Yes? EXIT_SUCCESS: EXIT_FAILURE;
    }
    }
    </syntaxhighlight>
    </syntaxhighlight>


    First we need to create a [http://doc.qt.io/qt-5/qapplication.html QApplication] object. This needs to be done exactly once in each program since it is needed for things such as [[Development/Tutorials/Localization/i18n|i18n]]. It also should be created before any other KDE or Qt object. A call to {{class|KLocalizedString}}::setApplicationDomain() is required to properly set the translation catalog and must be done before the next step happens.
    First we need to create a [http://doc.qt.io/qt-5/qapplication.html QApplication] object. This needs to be done exactly once in each program since it is needed for things such as [[Development/Tutorials/Localization/i18n|i18n]]. It also should be created before any other KDE or Qt object. A call to {{class|KLocalizedString}}::setApplicationDomain() is required to properly set the translation catalog and must be done before the next step happens.


    Então chegamos a {{class|KCmdLineArgs}}. Essa é a classe que se usaria para especificar uma linha de comando para, por exemplo, abrir o programa com um arquivo específico. No entanto, nesse tutorial, nós simplesmente iniciamos com o objeto {{class|KAboutData}} que nós criamos então podemos usar <tt>--version</tt> ou <tt>--author</tt>.
    The first KDE specific object we create in this program is {{class|KAboutData}}. This is the class used to store information about the program such as a short description, authors or license information. Pretty much every KDE application should use this class. We then call {{class|KAboutData}}::setApplicationData() to initialize the properties of the [http://doc.qt.io/qt-5/qapplication.html QApplication] object.


    Assim criamos um objeto {{class|KApplication}}. Isso precisa ser feito uma vez em cada programa, já que é necessário para coisas como [[Development/Tutorials/Localization/i18n|i18n]].
    Then we come to [http://doc.qt.io/qt-5/qcommandlineparser.html QCommandLineParser]. This is the class one would use to specify command line switches to, for example, open the program with a specific file. However, in this tutorial, we simply initialise it with the {{class|KAboutData}} object we created so we can use the <tt>--version</tt> or <tt>--author</tt> switches.


    Now we've done all the necessary KDE setup, we can move on to doing interesting things with our application. We're going to create a popup box but we're going to customise one of the buttons. To do this customisation, we need to use a {{class|KGuiItem}} object. The first argument in the {{class|KGuiItem}} constructor is the text that will appear on the item (in our case, a button). Then we have an option of setting an icon for the button but we don't want one so we just give it <tt>QString()</tt>. We then set the tooltip (what appears when you hover over an item) and finally the "What's This?" (accessed through right-clicking or Shift-F1) text.
    Now we've done all the necessary KDE setup, we can move on to doing interesting things with our application. We're going to create a popup box but we're going to customise one of the buttons. To do this customisation, we need to use a {{class|KGuiItem}} object. The first argument in the {{class|KGuiItem}} constructor is the text that will appear on the item (in our case, a button). Then we have an option of setting an icon for the button but we don't want one so we just give it <tt>QString()</tt>. We then set the tooltip (what appears when you hover over an item) and finally the "What's This?" (accessed through right-clicking or Shift-F1) text.


    Now we have our item, we can create our popup. We call the <tt>{{class|KMessageBox}}::questionYesNo()</tt> function which, by default, creates a message box with a "Yes" and a "No" button. The second argument is the text that will appear in the message box above the buttons. The third is the caption the window will have and finally we set the KGuiItem for (what would normally be) the "Yes" button to the <tt>KGuiItem yesButton</tt> we created.
    Now we have our item, we can create our popup. We call the <tt>{{class|KMessageBox}}::questionYesNo()</tt> function which, by default, creates a message box with a "Yes" and a "No" button. The second argument is the text that will appear in the message box above the buttons. The third is the caption the window will have and finally, we set the KGuiItem for (what would normally be) the "Yes" button to the <tt>KGuiItem yesButton</tt> we created.


    Note that all user-visible text is passed through the i18n() function; this is necessary for the UI to be translatable. More information on localization can be found in the [[Development/Tutorials/Localization/i18n|localization tutorial]].
    Note that all user-visible text is passed through the i18n() function; this is necessary for the UI to be translatable. More information on localization can be found in the [[Special:myLanguage/Development/Tutorials/Localization/i18n|localization tutorial]].


    We're all done as far as the code is concerned. Now to build it and try it out.
    We're all done as far as the code is concerned. Now to build it and try it out.
    Line 115: Line 103:
    == Build ==
    == Build ==


    You want to [[Development/Tutorials/CMake|use CMake]] for your build environment. You provide a file CMakeLists.txt, cmake uses this file to generate all Makefiles out of it.
    You want to [[Special:myLanguage/Development/Tutorials/CMake|use CMake]] for your build environment. You provide a file CMakeLists.txt, cmake uses this file to generate all Makefiles out of it.


    === CMakeLists.txt ===
    === CMakeLists.txt ===
    Line 122: Line 110:


    <syntaxhighlight lang="cmake">
    <syntaxhighlight lang="cmake">
    cmake_minimum_required(VERSION 3.0)
    project (tutorial1)
    project (tutorial1)


    cmake_minimum_required(VERSION 2.8.12 FATAL_ERROR)
    set(QT_MIN_VERSION "5.3.0")
    set(QT_MIN_VERSION "5.3.0")
    set(KF5_MIN_VERSION "5.2.0")
    set(KF5_MIN_VERSION "5.2.0")
    Line 133: Line 122:
    include(KDEInstallDirs)
    include(KDEInstallDirs)
    include(KDECMakeSettings)
    include(KDECMakeSettings)
    include(KDECompilerSettings)
    include(KDECompilerSettings NO_POLICY_SCOPE)
    include(FeatureSummary)
    include(FeatureSummary)


    Line 155: Line 144:
    add_executable(tutorial1 ${tutorial1_SRCS})
    add_executable(tutorial1 ${tutorial1_SRCS})


    <!--T:54-->
    target_link_libraries(tutorial1
    target_link_libraries(tutorial1
         Qt5::Widgets
         Qt5::Widgets
    Line 162: Line 152:
    )
    )


    install(TARGETS tutorial1  ${INSTALL_TARGETS_DEFAULT_ARGS})
    install(TARGETS tutorial1  ${KDE_INSTALL_TARGETS_DEFAULT_ARGS})
    </syntaxhighlight>
    </syntaxhighlight>


    Line 175: Line 165:
    === Make And Run ===
    === Make And Run ===


    To compile, link and install your program, you must have several software installed, e.g. cmake, make and gcc-c++, and the Qt 5 and KDE Frameworks development files. To be sure you have everything, best follow [[Getting_Started/Build/Environment|this install guide]].
    To compile, link and install your program, you must have several software installed, e.g. cmake, make and gcc-c++, and the Qt 5 and KDE Frameworks development files. To be sure you have everything, best follow [[Special:myLanguage/Getting_Started/Build/Environment|this install guide]].


    While you can run cmake directly inside the source code directory itself, it is a best practice, and actually enforced in some KDE software, to use a separate build directory and run cmake from there:
    While you can run cmake directly inside the source code directory itself, it is a best practice, and actually enforced in some KDE software, to use a separate build directory and run cmake from there:
    Line 195: Line 185:
    ==Moving On==
    ==Moving On==


    Now you can move on to [[Development/Tutorials/Using_KXmlGuiWindow|using KXmlGuiWindow]].
    Now you can move on to [[Special:myLanguage/Development/Tutorials/Using_KXmlGuiWindow|using KXmlGuiWindow]].


    {{Tip||The source code on this page applies only the current KDE Frameworks 5 ("KF5") version. For the older KDE Development Platform ("KDE4"), See [[Development/Tutorials/First_program/KDE4]]}}
    {{Tip||The source code on this page applies only the current KDE Frameworks 5 ("KF5") version. For the older KDE Development Platform ("KDE4"), See [[Special:myLanguage/Development/Tutorials/First_program/KDE4]]}}


    [[Category:C++]]
    [[Category:C++]]

    Revision as of 09:53, 10 February 2019

    Other languages:
    Hello World
    Tutorial Series   Beginner Tutorial
    Previous   C++, Qt, Building KDE
    What's Next   Tutorial 2 - KXmlGuiWindow
    Further Reading   CMake

    Resumo

    Your first program shall greet the world with a friendly "Hello World", what else? For that, we will use a KMessageBox and customise one of the buttons.

    Tip
    Para obter mais informações sobre qualquer classe que você encontra, você pode utilizar o mecanismo de busca 'kde'. Por exemplo, para procurar por informações sobre KMessageBox, apenas digite "kde:kmessagebox" no Konqueror, Rekonq ou KRunner, e você será levado para a documentação.


    Tip
    You might want to use KDevelop or QtCreator as IDE for your projects.


    O código

    All the code we need will be in one file, main.cpp. Create that file with the code below:

    #include <cstdlib>
    
    #include <QApplication>
    #include <QCommandLineParser>
    #include <KAboutData>
    #include <KLocalizedString>
    #include <KMessageBox>
    
    int main (int argc, char *argv[])
    {
        QApplication app(argc, argv);
        KLocalizedString::setApplicationDomain("tutorial1");
    
        
        KAboutData aboutData(
                             // The program name used internally. (componentName)
                             QStringLiteral("tutorial1"),
                             // A displayable program name string. (displayName)
                             i18n("Tutorial 1"),
                             // The program version string. (version)
                             QStringLiteral("1.0"),
                             // Short description of what the app does. (shortDescription)
                             i18n("Displays a KMessageBox popup"),
                             // The license this code is released under
                             KAboutLicense::GPL,
                             // Copyright Statement (copyrightStatement = QString())
                             i18n("(c) 2015"),
                             // Optional text shown in the About box.
                             // Can contain any information desired. (otherText)
                             i18n("Some text..."),
                             // The program homepage string. (homePageAddress = QString())
                             QStringLiteral("http://example.com/"),
                             // The bug report email address
                             // (bugsEmailAddress = QLatin1String("[email protected]")
                             QStringLiteral("[email protected]"));
        aboutData.addAuthor(i18n("Name"), i18n("Task"), QStringLiteral("[email protected]"),
                             QStringLiteral("http://your.website.com"), QStringLiteral("OSC Username"));
        KAboutData::setApplicationData(aboutData);
    
        QCommandLineParser parser;
        aboutData.setupCommandLine(&parser);
        parser.process(app);
        aboutData.processCommandLine(&parser);
        
        KGuiItem yesButton( i18n( "Hello" ), QString(),
                            i18n( "This is a tooltip" ),
                            i18n( "This is a WhatsThis help text." ) );
    
    return 
            KMessageBox::questionYesNo 
            (0, i18n( "Hello World" ), i18n( "Hello" ), yesButton ) 
            == KMessageBox::Yes? EXIT_SUCCESS: EXIT_FAILURE;
    }
    

    First we need to create a QApplication object. This needs to be done exactly once in each program since it is needed for things such as i18n. It also should be created before any other KDE or Qt object. A call to KLocalizedString::setApplicationDomain() is required to properly set the translation catalog and must be done before the next step happens.

    The first KDE specific object we create in this program is KAboutData. This is the class used to store information about the program such as a short description, authors or license information. Pretty much every KDE application should use this class. We then call KAboutData::setApplicationData() to initialize the properties of the QApplication object.

    Then we come to QCommandLineParser. This is the class one would use to specify command line switches to, for example, open the program with a specific file. However, in this tutorial, we simply initialise it with the KAboutData object we created so we can use the --version or --author switches.

    Now we've done all the necessary KDE setup, we can move on to doing interesting things with our application. We're going to create a popup box but we're going to customise one of the buttons. To do this customisation, we need to use a KGuiItem object. The first argument in the KGuiItem constructor is the text that will appear on the item (in our case, a button). Then we have an option of setting an icon for the button but we don't want one so we just give it QString(). We then set the tooltip (what appears when you hover over an item) and finally the "What's This?" (accessed through right-clicking or Shift-F1) text.

    Now we have our item, we can create our popup. We call the KMessageBox::questionYesNo() function which, by default, creates a message box with a "Yes" and a "No" button. The second argument is the text that will appear in the message box above the buttons. The third is the caption the window will have and finally, we set the KGuiItem for (what would normally be) the "Yes" button to the KGuiItem yesButton we created.

    Note that all user-visible text is passed through the i18n() function; this is necessary for the UI to be translatable. More information on localization can be found in the localization tutorial.

    We're all done as far as the code is concerned. Now to build it and try it out.

    Build

    You want to use CMake for your build environment. You provide a file CMakeLists.txt, cmake uses this file to generate all Makefiles out of it.

    CMakeLists.txt

    Create a file named CMakeLists.txt in the same directory as main.cpp with this content:

    cmake_minimum_required(VERSION 3.0)
    
    project (tutorial1)
    
    set(QT_MIN_VERSION "5.3.0")
    set(KF5_MIN_VERSION "5.2.0")
    
    find_package(ECM 1.0.0 REQUIRED NO_MODULE)
    set(CMAKE_MODULE_PATH ${ECM_MODULE_PATH} ${ECM_KDE_MODULE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/cmake)
    
    include(KDEInstallDirs)
    include(KDECMakeSettings)
    include(KDECompilerSettings NO_POLICY_SCOPE)
    include(FeatureSummary)
    
    # Find Qt modules
    find_package(Qt5 ${QT_MIN_VERSION} CONFIG REQUIRED COMPONENTS 
        Core    # QCommandLineParser, QStringLiteral
        Widgets # QApplication 
    )
    
    # Find KDE modules
    find_package(KF5 ${KF5_MIN_VERSION} REQUIRED COMPONENTS
        CoreAddons      # KAboutData
        I18n            # KLocalizedString
        WidgetsAddons   # KMessageBox
    )
    
    feature_summary(WHAT ALL INCLUDE_QUIET_PACKAGES FATAL_ON_MISSING_REQUIRED_PACKAGES)
        
    set(tutorial1_SRCS main.cpp)
    
    add_executable(tutorial1 ${tutorial1_SRCS})
    
    <!--T:54-->
    target_link_libraries(tutorial1
        Qt5::Widgets
        KF5::CoreAddons
        KF5::I18n
        KF5::WidgetsAddons
    )
    
    install(TARGETS tutorial1  ${KDE_INSTALL_TARGETS_DEFAULT_ARGS})
    

    The find_package() function locates the package that you ask it for (in this case ECM, Qt5, or KF5) and sets some variables describing the location of the package's headers and libraries. ECM, or Extra CMake Modules, is required to import special CMake files and functions for building KDE applications.

    Here we try to find the modules for Qt 5 and KDE Frameworks 5 required to build our tutorial. The necessary files are included by CMake so that the compiler can see them at build time. Minimum version numbers are set at the very top of CMakeLists.txt file for easier reference.

    Next we create a variable called tutorial1_SRCS using the set() function. In this case we simply set it to the name of our only source file.

    Then we use add_executable() to create an executable called tutorial1 from the source files listed in our tutorial1_SRCS variable. Afterwards, we link our executable to the necessary libraries using target_link_libraries() function. The line starting with install writes a default "install" target into the Makefile.

    Make And Run

    To compile, link and install your program, you must have several software installed, e.g. cmake, make and gcc-c++, and the Qt 5 and KDE Frameworks development files. To be sure you have everything, best follow this install guide.

    While you can run cmake directly inside the source code directory itself, it is a best practice, and actually enforced in some KDE software, to use a separate build directory and run cmake from there:

    mkdir build && cd build
    

    You can invoke CMake and make manually:

    cmake .. && make
    

    And launch it with:

    ./tutorial1
    

    Moving On

    Now you can move on to using KXmlGuiWindow.

    The source code on this page applies only the current KDE Frameworks 5 ("KF5") version. For the older KDE Development Platform ("KDE4"), See Special:myLanguage/Development/Tutorials/First_program/KDE4