Development/Tutorials/Kross/Call Functions in Kross

This tutorial shows how to deal with functions provided by a script. It builds upon the Kross Hello World tutorial and extends that tutorial where needed.

The source files

CMakeList.txt

project (krosshello) find_package(KDE4 REQUIRED) include_directories( ${KDE4_INCLUDES} ) set(krosshello_SRCS main.cpp mainwindow.cpp) kde4_add_executable(krosshello ${krosshello_SRCS}) target_link_libraries(krosshello ${KDE4_KDEUI_LIBS} ${KDE4_KROSSUI_LIBS})

main.cpp


include <QString>
include <KApplication>
include <KAboutData>
include <KMessageBox>
include <KCmdLineArgs>
include <KLocalizedString>
include "mainwindow.h"

int main (int argc, char *argv[]) {
	// Used to store information about a program.
	KAboutData aboutData("krosshello",
			0,
			ki18n("Kross Hello World"),
			"1.0",
			ki18n("Hello World application for Kross"),
			KAboutData::License_GPL,
			ki18n("(c) 2007"),
			ki18n("Some text..."),
			"http://kross.dipe.org",
			"submit@bugs.kde.org");
	// Access to the command-line arguments.
	KCmdLineArgs::init( argc, argv, &aboutData );
	// Initialize the application.
	KApplication app;
	// Create and show the main window.
	MainWindow* window = new MainWindow();
	window->show();

// Finally execute the application. return app.exec(); }

mainwindow.h


ifndef MAINWINDOW_H
define MAINWINDOW_H

include <QComboBox>
include <QLabel>
include <QLineEdit>

include <kross/core/action.h>

// The main window to display our combobox and the label.
class MainWindow : public QWidget
{
	Q_OBJECT
	public:
		// The constructor.
		MainWindow(QWidget *parent=0);
		private Q_SLOTS:
			// This slot is called when the item in the combobox is changed.
			void interpreterActivated(const QString &);
	private:
		QLineEdit* txtInputString;
		QLabel* lblMessage;
		QComboBox* cmbInterpreters;
		// We now have the action as class-member.
		Kross::Action* action;
};

endif

mainwindow.cpp


include "mw.h"

include <QVBoxLayout>
include <QDebug>

include <kross/core/manager.h>
include <kross/core/action.h>

// the constructor.
MainWindow::MainWindow(QWidget *parent) : QWidget(parent)
{
	txtInputString = new QLineEdit();
	lblMessage = new QLabel("Hello");
	cmbInterpreters = new QComboBox ();
	cmbInterpreters->addItem("Choose Interpreter", "");
	foreach(QString s, Kross::Manager::self().interpreters())
		cmbInterpreters->addItem(s);
	connect(cmbInterpreters, SIGNAL(activated(const QString &)),
			SLOT(interpreterActivated(const QString &)));
	QVBoxLayout *vLayout = new QVBoxLayout;
	vLayout->addWidget(cmbInterpreters);
	vLayout->addWidget(txtInputString);
	vLayout->addWidget(lblMessage);
	setLayout(vLayout);
	// This time we create the Kross::Action already within the
	// constructor and add the objects that should be accessible
	// from within scripting code.
	action = new Kross::Action(this, "MyScript");

   action->addObject(txtInputString, "MyInputString");

	action->addObject(cmbInterpreters, "MyInterpreter");
	action->addObject(lblMessage, "MyLabel");
}
// this slot is called when the active item of the combobox changes.
void MainWindow::interpreterActivated(const QString &strSelectedInterpreter)
{
	if(strSelectedInterpreter.isEmpty()) {
		lblMessage->setText("-");
		return;
	}
	// this time we are using external script files.
	QString filename;
	if(strSelectedInterpreter == "python")
		filename = "krossSigsSlots.py";
	else if(strSelectedInterpreter == "javascript")
		filename = "krossSigsSlots.js";
	else
		return;
	// set the script file that should be executed.
	action->setFile(filename);
	// finally execute the scripting code, i.e. preload
	action->trigger();
	// now we can call arbitrary functions
	QVariantList arguments;
	QVariant v;
	v.setValue( (QWidget*) txtInputString );
	arguments << v;

arguments << "Hello World"; QVariant result = action->callFunction("reverseString", arguments); lblMessage->setText(result.toString()); }