messageviewer.cpp Example File
messageviewer/messageviewer.cpp

    /****************************************************************************
    **
    ** This file is part of the Qt Extended Commercial Package.
    **
    ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
    **
    ** $QT_EXTENDED_DUAL_LICENSE$
    **
    ****************************************************************************/

    #include "messageviewer.h"
    #include "messagedelegate.h"
    #include "messagemodel.h"
    #include <QContactModel>
    #include <QContactListView>
    #include <QKeyEvent>
    #include <QLabel>
    #include <QMailMessageId>
    #include <QSoftMenuBar>
    #include <QStandardItemModel>
    #include <QtopiaServiceRequest>
    #include <QVBoxLayout>

    // A stackable widget allowing the selection of a Contact
    class ContactSelector : public QWidget
    {
        Q_OBJECT

    public:
        ContactSelector(QWidget* parent = 0)
            : QWidget(parent), listView(new QContactListView)
        {
            QLabel* label = new QLabel;
            label->setText(tr("Select a contact to view messages exchanged:"));
            label->setWordWrap(true);

            listView->setModel(&model);
            listView->setFrameStyle(QFrame::NoFrame);

            connect(listView, SIGNAL(activated(QModelIndex)), this, SLOT(activated(QModelIndex)));

            QVBoxLayout* layout = new QVBoxLayout(this);
            layout->addWidget(label);
            layout->addWidget(listView);
            // Adjust ContactSelector layout for attractive layout - not relevant to example discussion
            int horizontal = style()->pixelMetric(QStyle::PM_LayoutLeftMargin);
            int vertical = style()->pixelMetric(QStyle::PM_LayoutTopMargin);
            label->setContentsMargins(horizontal, vertical, horizontal, 0);
            layout->setContentsMargins(0, 0, 0, 0);
            // end-Adjust
        }

    signals:
        void contactSelected(const QContact& contact);

    protected slots:
        void activated(const QModelIndex& index) { emit contactSelected(model.contact(index)); }

    private:
        QContactModel model;
        QContactListView* listView;
    };

    // A stackable widget allowing the selection of a message
    class MessageSelector : public QWidget
    {
        Q_OBJECT

    public:
        MessageSelector(QWidget* parent = 0)
            : QWidget(parent), label(new QLabel), listView(new QListView)
        {
            label->setWordWrap(true);

            listView->setModel(&model);
            listView->setItemDelegate(&delegate);
            listView->setSelectionMode(QAbstractItemView::SingleSelection);
            listView->installEventFilter(this);

            connect(listView, SIGNAL(activated(QModelIndex)), this, SLOT(activated(QModelIndex)));

            QVBoxLayout* layout = new QVBoxLayout(this);
            layout->addWidget(label);
            layout->addWidget(listView);
            // Adjust MessageSelector layout for attractive layout - not relevant to example discussion
            int horizontal = style()->pixelMetric(QStyle::PM_LayoutLeftMargin);
            int vertical = style()->pixelMetric(QStyle::PM_LayoutTopMargin);
            label->setContentsMargins(horizontal, vertical, horizontal, 0);
            layout->setContentsMargins(0, 0, 0, 0);
            listView->setResizeMode(QListView::Adjust);
            listView->setLayoutMode(QListView::Batched);
            listView->setFrameStyle(QFrame::NoFrame);
            // end-Adjust
        }

    signals:
        void listPrepared();
        void messageSelected(const QMailMessageId& id);
        void done();

    public slots:
        void listMessages(const QContact& contact);

    protected slots:
        void activated(const QModelIndex& index) { emit messageSelected(model.messageId(index)); }

    protected:
        virtual bool eventFilter(QObject* obj, QEvent* event);

    private:
        MessageModel model;
        MessageDelegate delegate;
        QLabel* label;
        QListView* listView;
    };

    void MessageSelector::listMessages(const QContact& contact)
    {
        model.setContact(contact);

        if (model.isEmpty()) {
            label->setText(tr("No messages exchanged with %1").arg(contact.label()));
        } else {
            listView->selectionModel()->select(model.index(0, 0), QItemSelectionModel::Select);
            listView->scrollToTop();
            label->setText(tr("Select a message to view the content:"));
        }

        emit listPrepared();
    }
    // end-listMessages

    bool MessageSelector::eventFilter(QObject* obj, QEvent* event)
    {
        // We need to capture the back key, so it doesn't close our window
        if ((obj == listView) && (event->type() == QEvent::KeyPress)) {
            if (QKeyEvent* keyEvent = static_cast<QKeyEvent*>(event)) {
                if (keyEvent->key() == Qt::Key_Back) {
                    emit done();
                    return true;
                }
            }
        }

        return QWidget::eventFilter(obj, event);
    }

    MessageViewer::MessageViewer(QWidget *parent, Qt::WFlags f)
        : QWidget(parent, f),
          contactSelector(new ContactSelector),
          messageSelector(new MessageSelector)
    {
        setupUi(this);

        // Connect our components
        connect(contactSelector, SIGNAL(contactSelected(QContact)), messageSelector, SLOT(listMessages(QContact)));
        connect(messageSelector, SIGNAL(listPrepared()), this, SLOT(showMessageList()));
        connect(messageSelector, SIGNAL(messageSelected(QMailMessageId)), this, SLOT(viewMessage(QMailMessageId)));
        connect(messageSelector, SIGNAL(done()), this, SLOT(showContactList()));

        widgetStack->addWidget(contactSelector);
        widgetStack->addWidget(messageSelector);

        QVBoxLayout* layout = new QVBoxLayout(this);
        layout->addWidget(widgetStack);

        // Adjust MessageViewer
        layout->setContentsMargins(0, 0, 0, 0);

        // Necessary to create the menu (which contains our help entry):
        (void)QSoftMenuBar::menuFor(this);
        // end-Adjust
        showContactList();
    }

    MessageViewer::~MessageViewer()
    {
    }

    void MessageViewer::showMessageList()
    {
        widgetStack->setCurrentWidget(messageSelector);
    }

    void MessageViewer::viewMessage(const QMailMessageId& id)
    {
        // Request that some application display the selected message
        QtopiaServiceRequest req( "Messages", "viewMessage(QMailMessageId)" );
        req << id;
        req.send();
    }

    void MessageViewer::showContactList()
    {
        widgetStack->setCurrentWidget(contactSelector);
    }

    #include "messageviewer.moc"