C++ QFontDatabase::hasFamily方法代码示例

void tst_QFontDatabase::localizedFonts()
{
    QFontDatabase db;

    QVERIFY(db.hasFamily(QString::fromUtf8("ヒラギノ明朝 Pro")));
    QVERIFY(!db.hasFamily(QString::fromUtf8("NotValidFont")));
}

static QString defaultFontFamily()
{
    if (Utils::HostOsInfo::isMacHost())
        return QLatin1String("Monaco");

    const QString sourceCodePro("Source Code Pro");
    const QFontDatabase dataBase;
    if (dataBase.hasFamily(sourceCodePro))
        return sourceCodePro;

    if (Utils::HostOsInfo::isAnyUnixHost())
        return QLatin1String("Monospace");
    return QLatin1String("Courier");
}

void tst_QFont::defaultFamily()
{
    QFETCH(QFont::StyleHint, styleHint);
    QFETCH(QStringList, acceptableFamilies);

    QFont f;
    QFontDatabase db;
    f.setStyleHint(styleHint);
    const QString familyForHint(f.defaultFamily());

    // it should at least return a family that is available.
    QVERIFY(db.hasFamily(familyForHint));

    bool isAcceptable = false;
    Q_FOREACH (const QString& family, acceptableFamilies) {
        if (!familyForHint.compare(family, Qt::CaseInsensitive)) {
            isAcceptable = true;
            break;
        }
    }
    QVERIFY2(isAcceptable, msgNotAcceptableFont(familyForHint, acceptableFamilies));
}

void tst_QFontCache::clear()
{
#ifdef QT_BUILD_INTERNAL
    QFontEngine_startCollectingEngines();
#else
    // must not crash, at very least ;)
#endif

    QFontEngine *fontEngine = 0;

    {
        // we're never caching the box (and the "test") font engines
        // let's ensure we're not leaking them as well as the cached ones
        qt_setQtEnableTestFont(true);

        QFont f;
        f.setFamily("__Qt__Box__Engine__");
        f.exactMatch(); // loads engine
    }
    {
        QFontDatabase db;

        QFont f;
        f.setStyleHint(QFont::Serif);
        const QString familyForHint(f.defaultFamily());

        // it should at least return a family that is available
        QVERIFY(db.hasFamily(familyForHint));
        f.exactMatch(); // loads engine

        fontEngine = QFontPrivate::get(f)->engineForScript(QChar::Script_Common);
        QVERIFY(fontEngine);
        QVERIFY(QFontCache::instance()->engineCacheCount.value(fontEngine) > 0); // ensure it is cached

        // acquire the engine to use it somewhere else:
        // (e.g. like the we do in QFontSubset() or like QRawFont does in fromFont())
        fontEngine->ref.ref();

        // cache the engine once again; there is a special case when the engine is cached more than once
        QFontCache::instance()->insertEngine(QFontCache::Key(QFontDef(), 0, 0), fontEngine);
    }

    // use it:
    // e.g. fontEngine->stringToCMap(..);

    // and whilst it is alive, don't hesitate to add/remove the app-local fonts:
    // (QFontDatabase::{add,remove}ApplicationFont() clears the cache)
    QFontCache::instance()->clear();

    // release the acquired engine:
    if (fontEngine) {
        if (!fontEngine->ref.deref())
            delete fontEngine;
        fontEngine = 0;
    }

    // we may even exit the application now:
    QFontCache::instance()->cleanup();

#ifdef QT_BUILD_INTERNAL
    QList<QFontEngine *> leakedEngines = QFontEngine_stopCollectingEngines();
    for (int i = 0; i < leakedEngines.size(); ++i) qWarning() << i << leakedEngines.at(i) << leakedEngines.at(i)->ref.load();
    // and we are not leaking!
    QCOMPARE(leakedEngines.size(), 0);
#endif
}