problem with QMediaPlayer

valeriy

i created resourse file and added mp3 file
write 3 lines:

QMediaPlayer* player = new QMediaPlayer();
player->setMedia(QUrl("qrc:/sounds/psk.mp3"));
player->play();

application is started, there is win process, but does not appear on the screen
later, i changed code:

QMediaPlayer* player = new QMediaPlayer();
player->setMedia(QUrl(":/sounds/psk.mp3"));
player->play();

application is run on the screen, but now sound not play

my .pro file

QT += core gui multimedia

TARGET = test_cpp
CONFIG += console c++11
CONFIG -= app_bundle

TEMPLATE = app

SOURCES += main.cpp \
    Figure.cpp \
    GameField.cpp

HEADERS += \
    Figure.h \
    GameField.h

RESOURCES += \
    res.qrc

what am I doing wrong?

SGaist

Hi,

Do you mean that with qrc:/ the sound is playing but you have no UI ?

valeriy

@SGaist said:

Hi,

Do you mean that with qrc:/ the sound is playing but you have no UI ?

sound isn't playing and the application does not appear on the screen.
If i change qrc:/ to :/, sound isn`t playing, but application is running normally.
I noticed that happens only in this class:

class Button : public QObject, public QGraphicsPixmapItem
{
    Q_OBJECT
private:
    QPixmap *state1, *state2;
    void mousePressEvent(QGraphicsSceneMouseEvent *event);
    void hoverEnterEvent(QGraphicsSceneHoverEvent *event);
    void hoverLeaveEvent(QGraphicsSceneHoverEvent *event);
 
    //QMediaPlayer *hoverSound;
 
public:
    Button(const QPixmap& pixmap1, const QPixmap& pixmap2);
    ~Button();
 
signals:
    void clicked();
};

ps. sorry for my english :(

SGaist

Depending on your target platform reading from qrc is not possible. That's not a Qt limitation but a platform constraint. The native API used are not able to access data from Qt's resource. You should copy the file to a temporary folder provided by QStandardPaths and play it from there.

MajidKamali

I had the same problem.
It's because QMediaPlayer needs a QUrl and QUrl must start with something like qrc:/ or http:/ etc. otherwise string is an invalid QUrl and QUrl becomes empty.

QUrl url1("qrc:/path to your file in resources");
QUrl url2(":/path to your file in resources");
qDebug() << url1;
qDebug() << url2;

url2 is empty. because it's not a valid url.
I don't know if it is possible to disable validation in QUrl or not.
I add a "qrc" manually to my string when passing to QUrl

QUrl url("qrc" + ":/path to file in resources");

@SGaist why there is no access to library or binary file in some platforms? resources are internal and are in application binary.

SGaist

Your url1 should be correct.

What Version of Qt are you using ? On what platform ?

I've doubled checked the implementation of QMediaPlayer, if you have a recent enough Qt, it should do the temporary file trick automatically for you.

It's because the native API don't know how to handle files in Qt's resources.

MajidKamali

@SGaist I use Qt 5.4.1 on Ubuntu 14.04 64-bit

SGaist

It's been added to Qt 5.5.0