한국어
Qt
 

 

//나쁜예: C++ 내에서 QML 객체 수정
QObject *artistLabel = rootItem->findChildren("artistLabel");
artistLabel->setProperty("text", m_currentSong->artist);
...
QObject *nextButton = rootItem->findChildren("nextButton");
connect(nextButton, SIGNAL(clicked()), this, &MusicPlayer::nextSong);
QObject *musicPlayer = nextButton->parent();
QMetaObject::invokeMethod(musicPlayer, "startAnimation", Q_ARG(QVariant, duration));
 
//좋은예: QML의 C++ 객체 사용
//QML은 UI계층으로만 구현해야 한다. 이해하기 쉽다.
Text {
    text: musicPlayer.currentSong.artist
}
Button {
    onClicked: musicPlayer.nextSong()
}
Slider {
    value: musicPlayer.volume
}
 
 
//나쁜예: QML 프로퍼티에 상태 저장
class MusicPlayer : public QObject {
    Q_INVOKABLE void setVolume(int volume) {
        m_backend->setVolume(volume);
    }
}
property int volume: 50
Slider {
    value: volume
    
    onRightPressed: {
        volume = Math.min(100, volume + 5);
        musicPlayer.setVolume(volume);
    }
}
 
//좋은예: C++ 프로퍼티에 상태 저장
//더빠르고 유지보수가 용이하다.
class MusicPlayer : public QObject {
    Q_PROPERTY(int volume READ volume NOTIFY ...)
    
public:
    int volume() const { return m_volume; }
    Q_INVOKABLE void increaseVolume() {
        m_volume = qMin(100, volume + 5);
        m_backend->setVolume(m_volume);
    }
private:
    int m_volume = EAR_BLEEDING_LOUD;
}
Slider {
    value: musicPlayer.volume
    
    onRightPressed: musicPlayer.increaseVolume()
}