Difference between revisions of "Development/Tutorials/Kate/KTextEditor Example"

Revision as of 14:06, 31 August 2008

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


include <KApplication>
include <KAboutData>
include <KCmdLineArgs>

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


ifndef MAINWINDOW_H
define MAINWINDOW_H

include <KParts/MainWindow>
include <QtGui/QKeyEvent>



namespace KTextEditor
{

 class Document;
 class View;

}
class MainWindow : public KParts::MainWindow
{

 Q_OBJECT
 
 public:
   MainWindow(QWidget *parent=0);
 
 private slots:
   void clear();
   void openFile();

 private:
   void setupActions();
   KTextEditor::View *m_view;
   KTextEditor::Document *m_doc;

};

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


include "mainwindow.h"

include <KApplication>
include <KAction>
include <KLocale>
include <KActionCollection>
include <KStandardAction>
include <KFileDialog>
include <KMessageBox>
include <KIO/NetAccess>
include <KSaveFile>
include <QTextStream>
include <KXMLGUIFactory>




include <KTextEditor/Document>
include <KTextEditor/View>
include <KTextEditor/Editor>
include <KTextEditor/EditorChooser>



MainWindow::MainWindow(QWidget *)
{

 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");
 createShellGUI(true);

 guiFactory()->addClient(m_view);

 show ();

}
void MainWindow::setupActions()
{

 KStandardAction::quit(kapp, SLOT(quit()), actionCollection());
 KStandardAction::open(this, SLOT(openFile()), actionCollection());
 KStandardAction::clear(this, SLOT(clear()), actionCollection());

}
void MainWindow::clear()
{

 m_doc->clear();

}
void MainWindow::openFile()
{

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

}

The implementation is straight forward and self-explanatory. Some remarks:

MainWindow::Mainwindow()

First the editor component is created on the heap. After creating document() and view(), the GUI definitions are loaded from editorui.rc. The call guiFactory()->addClient(m_view) adds the kate parts menue and toolbar definitions to MainWindow. After that a full featured texteditor with syntax highlighting etc. is available for your application.

MainWindow::setupAction() defines three additional actions.

editorui.rc

<!DOCTYPE kpartgui SYSTEM "kpartgui.dtd"> <kpartgui name="editor" version="1">

<MenuBar>


 <Menu name="file" noMerge="1"><text>&File</text>

   <Action name="file_open" />
   <DefineGroup name="save_merge" append="save_merge" />
   <Separator/>

   <DefineGroup name="revert_merge" append="revert_merge"/>
   <DefineGroup name="print_merge" append="print_merge"/>
   <Separator/>

   <Action name="file_quit"/>
 </Menu>
 <Merge />

</MenuBar>
<ToolBar name="mainToolBar" noMerge="1"><text>Main Toolbar</text>

 <Action name="file_open" />
 <DefineGroup name="file_operations" />
 <Separator />
 <DefineGroup name="print_merge" />
 <Separator />
 <Action name="file_close" />
 <Separator />
 <DefineGroup name="edit_operations" />
 <Separator />
 <DefineGroup name="find_operations" />
 <Separator />
 <DefineGroup name="zoom_operations" />

</ToolBar>
<Menu name="ktexteditor_popup" noMerge="1">

 <DefineGroup name="popup_operations" />

</Menu>

</kpartgui>

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)

@@ Line 147: / Line 147: @@
 <code xml n>
 <!DOCTYPE kpartgui SYSTEM "kpartgui.dtd">
-<kpartgui name="editor" version="16">
+<kpartgui name="editor" version="1"> <!-- increase version number if you don't see changes after experimenting with this file -->
 <MenuBar>
@@ Line 162: / Line 162: @@
      <Action name="file_quit"/>
    </Menu>
+  <Merge />
 </MenuBar>