抽丝剥茧，由外及内 — 合久必分，分久必合 — 按需加载，资源不浪费，问题不易出
插件测试程序: GoldenDict_plugins_test.7z (19.8 MB)
内置fmodex插件、ffmpeg插件、bass插件、qtmediaplayer插件各一个，ocr插件两个，测试用mp3音频和图片文件文件各一个。
1. 插件公共接口
class GDCORE_EXPORT GDPObject : public QObject
{
Q_OBJECT
public:
explicit GDPObject(QObject *parent = nullptr) : QObject(parent), owner(nullptr)
{}
virtual ~GDPObject()
{}
virtual int type() const = 0; /*GDO_Type*/
virtual QString name() const = 0;
virtual QString author() const = 0;
virtual bool init() = 0;
int version() const;
QString fileName() const;
static QList<QPair<QString/*iid*/, QString/*path*/> > metaInfo(const QString &dir, const QString filter);
static GDPObject* loadObject(const QString &file, QObject *parent = nullptr);
void unload();/* owner deletelater */
signals:
void error( const QString& );
private:
class GDPObjOwner;
GDPObjOwner *owner;
};
2. AudioPlayer公共接口
class GDPAudioPlayer : public GDPObject
{
public:
explicit GDPAudioPlayer(QObject *parent = nullptr) : GDPObject(parent)
{}
virtual ~GDPAudioPlayer()
{}
int type() const { return GDOT_AudioPlayer; }
/// Initialize audio device and playback environment
//virtual bool init() = 0;
/// Stops current playback if any, copies the audio buffer, then plays the duplication.
/// Returns an error message in case of immediate failure; an empty string in case of success.
virtual QString play( const QByteArray &audioBuffer ) = 0;
virtual QString playFile( const QString &file ) = 0;
/// Stops current playback if any.
virtual void stop() = 0;
};
#define GDPAudioPlayer_iid "gdp.AudioPlayer"
Q_DECLARE_INTERFACE(GDPAudioPlayer, GDPAudioPlayer_iid)
AudioPlayer插件实例：
class QtMediaplayer : public GDPAudioPlayer
{
Q_OBJECT
#if (QT_VERSION >= QT_VERSION_CHECK(5, 0, 0))
Q_PLUGIN_METADATA(IID "adp/Qt Multimedia")
Q_INTERFACES(GDPAudioPlayer)
#endif
public:
QtMediaplayer();
~QtMediaplayer();
bool init() override;
QString name() const { return tr("Qt Multimedia"); }
QString author() const { return "GoldenDict Official"; }
QString play( const QByteArray &_audioBuffer ) override;
QString playFile( const QString &file ) override;
void stop() override;
private slots:
void onMediaPlayerError(QMediaPlayer::Error);
private:
QMediaPlayer *player; ///< Depends on audioBuffer.
QBuffer audioBuffer;
};
QtMediaplayer::QtMediaplayer() : GDPAudioPlayer(),
player(0)
{
}
QtMediaplayer::~QtMediaplayer()
{
if(player)
delete player;
}
bool QtMediaplayer::init()
{
player = new QMediaPlayer(nullptr, QMediaPlayer::StreamPlayback );
connect( player, SIGNAL(error(QMediaPlayer::Error)),
this, SLOT(onMediaPlayerError(QMediaPlayer::Error)) );
return true;
}
QString QtMediaplayer::play(const QByteArray &_audioBuffer)
{
if(player)
{
stop();
audioBuffer.setData( _audioBuffer );
if( !audioBuffer.open( QIODevice::ReadOnly ) )
return tr( "Couldn't open audio buffer for reading." );
player->setMedia( QMediaContent(), &audioBuffer );
player->play();
}
return QString();
}
QString QtMediaplayer::playFile( const QString &file )
{
if(player)
{
stop();
player->setMedia( QMediaContent(QUrl::fromLocalFile(file)) );
player->play();
}
return QString();
}
void QtMediaplayer::stop()
{
if(player)
{
player->setMedia( QMediaContent() ); // Forget about audioBuffer.
if(audioBuffer.isOpen()) {
audioBuffer.close();
audioBuffer.setData( QByteArray() ); // Free memory.
}
}
}
void QtMediaplayer::onMediaPlayerError(QMediaPlayer::Error err)
{
QString errstr = player->errorString();
if(errstr.isEmpty())
errstr = tr("Error==%1").arg(err);
emit error( errstr );
}
#if (QT_VERSION < QT_VERSION_CHECK(5, 0, 0))
Q_EXPORT_PLUGIN(QtMediaplayer)
#endif
3. OCR划词共接口
class GDPOcrText : public GDPObject
{
public:
typedef QList<QPair<QString/*id*/, QString/*name*/> > OCR_LAN;
typedef QMap<QString /*area*/, OCR_LAN > OCR_LANS;
public:
explicit GDPOcrText(QObject *parent = nullptr) : GDPObject(parent)
{}
virtual ~GDPOcrText()
{}
int type() const { return GDOT_OcrWords; }
virtual void enableLans(const QStringList &lans, const QString &area) = 0;
virtual OCR_LANS getAreaLans() const = 0;
virtual void setDataPath(const QString &datadir) = 0;
virtual QString dataPath() const = 0;
virtual void ocrScreen() = 0;
virtual void ocrMemory(const QByteArray &bmpdata) = 0; /* bmp data */
virtual void ocrFile(const QString &file) = 0;
virtual bool isWorking() const = 0;
virtual void stop() = 0;
};
#define GDPOcrObject_iid "gdp.OcrText"
Q_DECLARE_INTERFACE(GDPOcrText, GDPOcrObject_iid)