Development/Tutorials/Kate/KTextEditor Example

    From KDE TechBase

    Abstract

    We build a small application using KTexteditor. This example supports syntax highlighting and other useful features. We see how to use KTextEditor.


    The Code

    main.cpp

    1. include <KApplication>
    2. include <KAboutData>
    3. include <KCmdLineArgs>
    1. include "mainwindow.h"

    int main (int argc, char *argv[]) {

     KAboutData aboutData( "editor", "editor",
         ki18n("Editor"), "1.0",
         ki18n("A simple text area which can load and save."),
         KAboutData::License_GPL,
         ki18n("Copyright (c) 2007 Developer") );
     KCmdLineArgs::init( argc, argv, &aboutData );
     KApplication app;
    
     MainWindow* window = new MainWindow();
     window->show();
     return app.exec();
    

    }

    In main.cpp just defines aboutData and app and shows Mainwindow.

    mainwindow.h

    1. ifndef MAINWINDOW_H
    2. define MAINWINDOW_H
    1. include <KXmlGuiWindow>
    2. include <QtGui/QKeyEvent>


    namespace KTextEditor {

     class Document;
     class View;
    

    }

    class MainWindow : public KXmlGuiWindow {

     Q_OBJECT
     
     public:
       MainWindow(QWidget *parent=0);
     
     private slots:
       void newFile();
       void openFile();
       void saveFile();
       void saveFileAs();
    
     private:
       void setupActions();
       QString fileName;
       KTextEditor::View *m_view;
       KTextEditor::Document *m_doc;
    

    };

    1. endif

    Class MainWindow is a successor of KXmlGuiWindow and contains KTextEditor (document and view) as a private Variable. There are also some useful methods defined.

    mainwindow.cpp

    1. include "mainwindow.h"
    1. include <KApplication>
    2. include <KAction>
    3. include <KLocale>
    4. include <KActionCollection>
    5. include <KStandardAction>
    6. include <KFileDialog>
    7. include <KMessageBox>
    8. include <KIO/NetAccess>
    9. include <KSaveFile>
    10. include <QTextStream>
    11. include <kxmlguifactory.h>


    1. include <ktexteditor/document.h>
    2. include <ktexteditor/view.h>
    3. include <ktexteditor/editor.h>
    4. include <ktexteditor/editorchooser.h>


    MainWindow::MainWindow(QWidget *parent)

       : KXmlGuiWindow(parent),
         fileName(QString()) //new
    

    {

     KTextEditor::Editor *editor = KTextEditor::EditorChooser::editor();
    
     if (!editor) {
       KMessageBox::error(this, i18n("A KDE text-editor component could not be found;\n"
    

    "please check your KDE installation."));

       kapp->exit(1);
     }
    
     m_doc = editor->createDocument(0);
     m_view = qobject_cast<KTextEditor::View*>(m_doc->createView(this));
    
     setCentralWidget(m_view);
     setupActions();
    
     setXMLFile("editorui.rc");
     guiFactory()->addClient(m_view);
    
     show ();
    

    }

    void MainWindow::setupActions() {

     KAction* clearAction = new KAction(this);
     clearAction->setText(i18n("Clear"));
     clearAction->setIcon(KIcon("document-new"));
     clearAction->setShortcut(Qt::CTRL + Qt::Key_W);
     actionCollection()->addAction("clear", clearAction);
     connect(clearAction, SIGNAL(triggered(bool)),m_doc, SLOT(clear()));
     KStandardAction::quit(kapp, SLOT(quit()), actionCollection());
     KStandardAction::open(this, SLOT(openFile()), actionCollection()); //new
     KStandardAction::openNew(this, SLOT(newFile()), actionCollection()); //new
    
     setupGUI();
    

    }

    void MainWindow::newFile() {

     fileName.clear();
     m_doc->clear();
    

    }

    void MainWindow::saveFileAs() {

     m_doc->documentSaveAs();
    

    }

    void MainWindow::saveFile() {

     m_doc->documentSave();
    

    }

    void MainWindow::openFile() {

     m_view->document()->openUrl(KFileDialog::getOpenFileName());
    

    }

    The implementation is straight forward and self-explanatory.

    editorui.rc

    <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE kpartgui SYSTEM "kpartgui.dtd"> <gui name="editor" version="1">

     <ToolBar name="mainToolBar" >
       <text>Main Toolbar</text>
       <Action name="clear" />
     </ToolBar>
     <MenuBar>
       <Menu name="file" >
         <Action name="clear" />
       </Menu>
     </MenuBar>
    

    </gui>

    CMakeLists.txt

    project(editor)

    find_package(KDE4 REQUIRED) include_directories(${KDE4_INCLUDES})

    set(editor_SRCS

     main.cpp
     mainwindow.cpp
    

    )

    kde4_add_executable(editor ${editor_SRCS})

    target_link_libraries(editor ${KDE4_KDEUI_LIBS}

                                ${KDE4_KIO_LIBS}
                                ${KDE4_KTEXTEDITOR_LIBS})
    
    

    install(TARGETS editor DESTINATION ${BIN_INSTALL_DIR}) install(FILES editorui.rc

           DESTINATION ${DATA_INSTALL_DIR}/editor)