QMediaPlayer & QMediaPlaylist - Delete Item (Qt 5.3)

mpcarlos87

Hello all,

Im developing a music player as a learning application to integrate QML and C++ with QT.

I have the class to manage the QMediaPlayer and the QMediaPlaylist in C++ and the QML is only for UI (or little functions in JS). I have the list of songs as a listview and im deleting a song from the playlist when I drag the item out of the list. When I delete a song after the playing one, it works perfect but i'm having problems deleting songs in the list before the played song. The thing is , if the song deleted is before in the playlist i must control the index of the QMediaPlaylist and the position of the QMediaPlayer. I tried to set the position of the player once the "seekableChanged" of the QMediaPlayer is thrown, but the song starts at position 0 every time despite the position seems to be correctly set.

Here is the code of the method to delete songs:

@void Player::DeleteSong(int index)
{
//Only deletes the songs different at the current played/paused
if(m_mediaPlaylist->currentIndex() != index)
{
QMediaPlayer::State originalState = m_player->state();
int currentIndex = m_mediaPlaylist->currentIndex();
qint64 position = m_player->position();

    //If the song deleted is before
    if(index < currentIndex)
    {
        //Save the position of the player to set it when seekableChanged is thrown
        m_previousPosition = position;
        m_player->pause();
        m_mediaPlaylist->removeMedia(index);
        //Set the song to the currentIndex-1 because the song deleted was before
        m_mediaPlaylist->setCurrentIndex(currentIndex-1);
    }
    //Else the song deleted is after
    else
    {
        m_mediaPlaylist->removeMedia(index);
    }

    //Set the original state again
    switch(originalState){
       case QMediaPlayer::PlayingState:
            m_player->play();
            break;
    }
    
    //Emit delete song to update the UI in QML
    emit deleteSongSignal(index);
}

}@

SeekableSlot:

@void Player::seekableChangedSlot(bool seekable)
{
if(seekable){
if(m_previousPosition>0){
qDebug()<<"Set position in seekable: " << m_previousPosition;
m_player->setPosition(m_previousPosition);
m_previousPosition = 0;
}
}
}@

Position Changed Slot:
@void Player::positionChangedSlot(qint64 position){
qDebug()<<"positionChangedSlot: "<<position;
QString timeString = GetTimeString(position);
//Notify the UI to set the slider position
emit sliderPositionChangedSignal(position,timeString);
}@

This is the output:

bq. //Playing state
positionChangedSlot: 5765
positionChangedSlot: 6780
//After delete the song
positionChangedSlot: 0
positionChangedSlot: 0
Set position in seekable: 7434
positionChangedSlot: 7434
//It is set well but returns to position 0 (Why!?)
positionChangedSlot: 0
positionChangedSlot: 771
positionChangedSlot: 1785

Anyone knows why my player goes to position 0 after i set it in the seekable slot?

Thank you so much!

PD: I use the setSosition with a slider from qml (it emits a value and I set the new position from C++ and it works perfect!)

mpcarlos87

Anyone could give me a little shine in this darkness? I tried to solve the problem so many times but I still didn't manage to make it work.

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QMediaPlayer & QMediaPlaylist - Delete Item (Qt 5.3)