Development/Tutorials/Programming Tutorial KDE 4/Using KConfig

Abstract

In this tutorial, we're going to be showing you how to utilise KConfig XT in an application. It is recommended that you read Development/Tutorials/Using KConfig XT before continuing in order to familiarise yourself with the framework.

Prerequisites

Tutorial 3 - KActions

Development/Tutorials/Using_KConfig_XT

KConfig XT

At first we make new File called tutorial4.kcfg within the source directory of your project.

<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE kcfg SYSTEM "http://www.kde.org/standards/kcfg/1.0/kcfg.xsd"> <kcfg> <kcfgfile name="kjotsrc"/> <include>kglobalsettings.h</include> <group name="kjots"> <entry name="showAction" type="Bool"> <label>Whether setupAction is called</label> <default>true</default> </entry> </group> </kcfg>

This code makes a setting of the type bool, which determines whether we want to do something. Then we set the default value to be true.

Always start the value of <entry name=""> in lower case since KConfig XT sets them to lower case within the generated headers either way. If you don't this could give you some nearly untraceable errors

Now we make a new File called tutorial4.kcfgc.

File=tutorial4.kcfg ClassName=tutorial4 Singleton=true Mutators=true

This should set up your configuration for now.

The Code

mainwindow.h


ifndef MAINWINDOW_H
define MAINWINDOW_H

include <KXmlGuiWindow>
include <KTextEdit>



class MainWindow : public KXmlGuiWindow
{
	public:
		MainWindow(QWidget *parent=0);
	private:
		KTextEdit* textArea;
		void setupActions();
		void setupConfig();
		void readConfig();
		void saveSettings();
		int m_showAction;
};

endif

There are some new voids in here, as well as m_showAction witch determines the value stored in KConfig XT. Despite that value being a bool we can actually use an integer here, since the type is converted either way.

mainwindow.cpp


include "mainwindow.h"
include "tutorial4.h"

include <KApplication>
include <KAction>
include <KLocale>
include <KActionCollection>
include <KStandardAction>
include <KConfigDialog>

MainWindow::MainWindow(QWidget *parent) : KXmlGuiWindow(parent)
{
	textArea = new KTextEdit;
	setCentralWidget(textArea);
	setupConfig();
}
void MainWindow::setupActions()
{
	QAction* clearAction = actionCollection()->addAction( "clear" );
	clearAction->setText(i18n("Clear"));
	clearAction->setIcon(KIcon("filenew"));
	clearAction->setShortcut(Qt::CTRL+ Qt::Key_W);
	connect(clearAction, SIGNAL(triggered(bool)), textArea, SLOT(clear()));
	KStandardAction::quit(kapp, SLOT(quit()), actionCollection());
	setupGUI();
}
void MainWindow::setupConfig()
{
	readConfig();	

	
}
void MainWindow::readConfig() {
	m_showAction    = tutorial4::showAction();
	if(m_showAction = (true)) 
		setupActions();
}
void MainWindow::saveSettings() { 
	tutorial4::setShowAction(m_showAction);
	tutorial4::self()->writeConfig();
}

At first we import "tutorial4.h", which should be auto-generated at runtime by KConfig XT every time you compile this. MainWindow and SetupActions are copied from the tutorials before. The only thing new is that we now call a new void called setupConfig. This then calls readConfig. We could also call saveSettings(but only after we called readConfig), but since we don't change any values there this is more of a "proof of concept".

Within readConfig we assign m_showAction the value of the setting showAction. If this returns true setupsActions makes buttons and all that. When false it doesn't.

The setShowActions() in saveSettings() overwrites showAction with a value of your choice, in this case with itself. Then you need to call writeConfig() to apply the changes you made.

main.cpp


include "mainwindow.h"




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

int main (int argc, char *argv[])
{
	KAboutData aboutData( "tutorial4", "tutorial4",
			      "0.4", "KMessageBox popup",
	 KAboutData::License_GPL, "(c) 2007" );
	KCmdLineArgs::init( argc, argv, &aboutData );
	KApplication app;
	MainWindow* window = new MainWindow();
	window->show();
	return app.exec();

}

No news in here

tutorial3ui.rc

TODO

CMake

TODO

CMakeLists.txt

PROJECT(tutorial4)

FIND_PACKAGE(KDE4 REQUIRED) INCLUDE_DIRECTORIES( ${KDE4_INCLUDES} ${CMAKE_CURRENT_BINARY_DIR})

SET(tutorial4_SRCS


 main.cpp
 mainwindow.cpp

)
KDE4_ADD_KCFG_FILES(tutorial4_SRCS settings.kcfgc)
KDE4_ADD_EXECUTABLE(tutorial4 ${tutorial4_SRCS})
TARGET_LINK_LIBRARIES( tutorial4 ${KDE4_KDEUI_LIBS})

install( TARGETS tutorial4 DESTINATION ${BIN_INSTALL_DIR}) install( FILES tutorial4ui.rc DESTINATION ${DATA_INSTALL_DIR}/tutorial4) install( FILES tutorial4.kcfg DESTINATION ${KCFG_INSTALL_DIR} )

Moving On