/**************************************************************************** ** ** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies). ** Contact: http://www.qt-project.org/legal ** ** This file is part of Qt Creator. ** ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and Digia. For licensing terms and ** conditions see http://qt.digia.com/licensing. For further information ** use the contact form at http://qt.digia.com/contact-us. ** ** GNU Lesser General Public License Usage ** Alternatively, this file may be used under the terms of the GNU Lesser ** General Public License version 2.1 as published by the Free Software ** Foundation and appearing in the file LICENSE.LGPL included in the ** packaging of this file. Please review the following information to ** ensure the GNU Lesser General Public License version 2.1 requirements ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. ** ** In addition, as a special exception, Digia gives you certain additional ** rights. These rights are described in the Digia Qt LGPL Exception ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. ** ****************************************************************************/ #include "main.h" #include MyMain::MyMain(QWidget *parent, Qt::WFlags flags) : QWidget(parent, flags) { ui.setupUi(this); connect(ui.comboBox, SIGNAL(currentIndexChanged(int)), this, SLOT(select(int))); } void MyMain::add(IComboEntry *obj) { m_entries.append(obj); ui.comboBox->addItem(obj->title()); } void MyMain::select(int index) { IComboEntry *entry = m_entries.at(index); // with multiple inheritance we would use qobject_cast here // instead we use query, to get the components if they exist IText1 *t1 = Aggregation::query(entry); IText2 *t2 = Aggregation::query(entry); IText3 *t3 = Aggregation::query(entry); // set the label texts and enable/disable, depending on whether // the respective interface implementations exist ui.text1->setText(t1 ? t1->text() : tr("N/A")); ui.text2->setText(t2 ? t2->text() : tr("N/A")); ui.text3->setText(t3 ? t3->text() : tr("N/A")); ui.text1->setEnabled(t1); ui.text2->setEnabled(t2); ui.text3->setEnabled(t3); } MyMain::~MyMain() { // the following deletes all the Aggregate and IComboEntry and ITextX // objects, as well as any other components we might have added qDeleteAll(m_entries); } int main(int argc, char *argv[]) { QApplication app(argc, argv); MyMain w; // create and set up some objects // the first does only implement the required IComboEntry // we don't need an aggregation for this IComboEntry *obj1 = new IComboEntry("Entry without text"); // the second additionally provides an IText2 implementation // adding a component to the aggregation is done by setting the aggregation as the parent of the component Aggregation::Aggregate *obj2 = new Aggregation::Aggregate; obj2->add(new IComboEntry("Entry with text 2")); obj2->add(new IText2("This is a text for label 2")); // and so on... two more objects... Aggregation::Aggregate *obj3 = new Aggregation::Aggregate; obj3->add(new IComboEntry("Entry with text 1 and 2")); obj3->add(new IText1("I love Qt!")); obj3->add(new IText2("There are software companies...")); Aggregation::Aggregate *obj4 = new Aggregation::Aggregate; obj4->add(new IComboEntry("Entry with text 1 and 3")); obj4->add(new IText1("Some text written here.")); obj4->add(new IText3("I'm a troll.")); // the API takes IComboEntries, so we convert the them to it // the MyMain object takes the ownership of the whole aggregations w.add(Aggregation::query(obj1)); w.add(Aggregation::query(obj2)); w.add(Aggregation::query(obj3)); w.add(Aggregation::query(obj4)); w.show(); return app.exec(); }