googlesuggest.cpp Example File

network/googlesuggest/googlesuggest.cpp
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#include "googlesuggest.h"

#define GSUGGEST_URL "http://google.com/complete/search?output=toolbar&q=%1"

GSuggestCompletion::GSuggestCompletion(QLineEdit *parent): QObject(parent), editor(parent)
{
    popup = new QTreeWidget;
    popup->setWindowFlags(Qt::Popup);
    popup->setFocusPolicy(Qt::NoFocus);
    popup->setFocusProxy(parent);
    popup->setMouseTracking(true);

    popup->setColumnCount(2);
    popup->setUniformRowHeights(true);
    popup->setRootIsDecorated(false);
    popup->setEditTriggers(QTreeWidget::NoEditTriggers);
    popup->setSelectionBehavior(QTreeWidget::SelectRows);
    popup->setFrameStyle(QFrame::Box | QFrame::Plain);
    popup->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    popup->header()->hide();

    popup->installEventFilter(this);

    connect(popup, SIGNAL(itemClicked(QTreeWidgetItem*,int)),
            SLOT(doneCompletion()));

    timer = new QTimer(this);
    timer->setSingleShot(true);
    timer->setInterval(500);
    connect(timer, SIGNAL(timeout()), SLOT(autoSuggest()));
    connect(editor, SIGNAL(textEdited(QString)), timer, SLOT(start()));

    connect(&networkManager, SIGNAL(finished(QNetworkReply*)),
            this, SLOT(handleNetworkData(QNetworkReply*)));

}

GSuggestCompletion::~GSuggestCompletion()
{
    delete popup;
}

bool GSuggestCompletion::eventFilter(QObject *obj, QEvent *ev)
{
    if (obj != popup)
        return false;

    if (ev->type() == QEvent::MouseButtonPress) {
        popup->hide();
        editor->setFocus();
        return true;
    }

    if (ev->type() == QEvent::KeyPress) {

        bool consumed = false;
        int key = static_cast<QKeyEvent*>(ev)->key();
        switch (key) {
        case Qt::Key_Enter:
        case Qt::Key_Return:
            doneCompletion();
            consumed = true;

        case Qt::Key_Escape:
            editor->setFocus();
            popup->hide();
            consumed = true;

        case Qt::Key_Up:
        case Qt::Key_Down:
        case Qt::Key_Home:
        case Qt::Key_End:
        case Qt::Key_PageUp:
        case Qt::Key_PageDown:
            break;

        default:
            editor->setFocus();
            editor->event(ev);
            popup->hide();
            break;
        }

        return consumed;
    }

    return false;
}

void GSuggestCompletion::showCompletion(const QStringList &choices, const QStringList &hits)
{

    if (choices.isEmpty() || choices.count() != hits.count())
        return;

    const QPalette &pal = editor->palette();
    QColor color = pal.color(QPalette::Disabled, QPalette::WindowText);

    popup->setUpdatesEnabled(false);
    popup->clear();
    for (int i = 0; i < choices.count(); ++i) {
        QTreeWidgetItem * item;
        item = new QTreeWidgetItem(popup);
        item->setText(0, choices[i]);
        item->setText(1, hits[i]);
        item->setTextAlignment(1, Qt::AlignRight);
        item->setTextColor(1, color);
    }
    popup->setCurrentItem(popup->topLevelItem(0));
    popup->resizeColumnToContents(0);
    popup->resizeColumnToContents(1);
    popup->adjustSize();
    popup->setUpdatesEnabled(true);

    int h = popup->sizeHintForRow(0) * qMin(7, choices.count()) + 3;
    popup->resize(popup->width(), h);

    popup->move(editor->mapToGlobal(QPoint(0, editor->height())));
    popup->setFocus();
    popup->show();
}

void GSuggestCompletion::doneCompletion()
{
    timer->stop();
    popup->hide();
    editor->setFocus();
    QTreeWidgetItem *item = popup->currentItem();
    if (item) {
        editor->setText(item->text(0));
        QMetaObject::invokeMethod(editor, "returnPressed");
    }
}

void GSuggestCompletion::autoSuggest()
{
    QString str = editor->text();
    QString url = QString(GSUGGEST_URL).arg(str);
    networkManager.get(QNetworkRequest(QString(url)));
}

void GSuggestCompletion::preventSuggest()
{
    timer->stop();
}

void GSuggestCompletion::handleNetworkData(QNetworkReply *networkReply)
{
    QUrl url = networkReply->url();
    if (!networkReply->error()) {
        QStringList choices;
        QStringList hits;

        QByteArray response(networkReply->readAll());
        QXmlStreamReader xml(response);
        while (!xml.atEnd()) {
            xml.readNext();
            if (xml.tokenType() == QXmlStreamReader::StartElement)
                if (xml.name() == "suggestion") {
                    QStringRef str = xml.attributes().value("data");
                    choices << str.toString();
                }
            if (xml.tokenType() == QXmlStreamReader::StartElement)
                if (xml.name() == "num_queries") {
                    QStringRef str = xml.attributes().value("int");
                    hits << str.toString();
                }
        }

        showCompletion(choices, hits);
    }

    networkReply->deleteLater();
}

© 2016 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.