QmediaPlayer in another Thread does not reproduce any sound

[Lemoeb]

Hello everyone,
I did a search in the forum but I did not find anything about it.
I made a program to simulate a slot machine.
Everything works more or less well if it was not that the sound of the slot I put is not played in the scondario thread.
Documenting I saw that in order to be able to play the sound without interrupting the execution of the main thread is to use a secondary thread.
I tested the thing under Windows and it works, but under Linux there is no way to reproduce the sound.
This is wath i wrote:

mainWindow.h

ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QTimer>
#include <QSound>
#include <QThread>
#include <QMediaPlayer>
#include <QMediaPlaylist>
#include "ritardo.h"
#include "roller.h"


namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

private slots:
    void on_pushButton_clicked();
    int getRand(int,int);

    void on_pushButton_2_clicked();

private:
    Ui::MainWindow *ui;
    WorkerThread *workerThread;

};

#endif // MAINWINDOW_H

roller.h

ifndef ROLLER_H
#define ROLLER_H
#include <QThread>
#include <QMediaPlayer>
#include <QFileInfo>
#include <QSound>



class WorkerThread : public QThread
{
    Q_OBJECT
    void run() override {
        QString result;

        this->playerM = new QMediaPlayer();
        this->playerM->setMedia(QUrl("file:///home/lemoeb/sound/roll.mp3"));
        
        this->playerM->setVolume(100);
     
        emit resultReady(result);
    }

signals:
    void resultReady(const QString &s);
private:
    QMediaPlayer *playerM;
    QSound *test;
public:
    WorkerThread(){};
    ~WorkerThread(){

    }
    void stopPlayer(){
        this->playerM->stop();

    }
    void startPlayer(){
        this->playerM->play();
    }


};


#endif // ROLLER_H

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QTime>




MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{

    ui->setupUi(this);
    workerThread = new WorkerThread();
    workerThread->start();
}

MainWindow::~MainWindow()
{
    delete ui;
}

int MainWindow::getRand(int low,int high){

    return qrand() % ((high + 1) - low) + low;
}



void MainWindow::on_pushButton_clicked()
{

    int a,b,c,d=0;
    int stop1,stop2,stop3,stop4=0;
    int exit=0;

   workerThread->startPlayer();


    QTime time = QTime::currentTime();
    qsrand((uint)time.msec());
    for (int i=500;i>1;i--){
        if (i>470){
            exit=0;
          while (exit==0){
             int n=getRand(1,9);
             if (a!=n){
                 a=n;
                 exit=1;
             }
          }
          QString immagine=QString::number(getRand(1,9));
          QPixmap pixmap("./image/" + immagine +".png");
          ui->label1->setPixmap(pixmap);
          ui->label1->repaint();


        }
        else
        {
            if (stop1==0){

                stop1=1;
            }
        }
        if (i>440){
          exit=0;
          while (exit==0){
             int n=getRand(1,9);
             if (b!=n){
                 b=n;
                 exit=1;
             }
          }
         // b=getRand(1,9);

          QPixmap pixmap2("./image/" + QString::number(getRand(1,9)) +".png");
          ui->label2->setPixmap(pixmap2);
          ui->label2->repaint();
        }
        if (i>410){
          //c=getRand(1,9);
          exit=0;
          while (exit==0){
             int n=getRand(1,9);
             if (c!=n){
                 c=n;
                 exit=1;
             }
          }
          QPixmap pixmap3("./image/" + QString::number(getRand(1,9)) +".png");
          ui->label3->setPixmap(pixmap3);
          ui->label3->repaint();
        }
        if (i>380){
          d=getRand(1,9);
          exit=0;
          while (exit==0){
             int n=getRand(1,9);
             if (d!=n){
                 d=n;
                 exit=1;
             }
          }
          QPixmap pixmap4("./image/" + QString::number(getRand(1,9)) +".png");
          ui->label4->setPixmap(pixmap4);
          ui->label4->repaint();
        }
        ui->lblCount->setText(QString::number(i));
        if (i>380){
            QTime timeStart = QTime::currentTime();
            QTime timeStop=timeStart.addMSecs(50);
            while (timeStart < timeStop){
                timeStart = QTime::currentTime();
            }
        }
        else
        {
            //this->workerThread->stopPlayer();
            ui->lblCount->setText("STOP");
        }


    }


    //QPixmap pixmap("./image/" + immagine +".png");

}

void MainWindow::on_pushButton_2_clicked()
{
    //QSound::play("./sound/stop.wav");

   // roll.play();
}

SlotMachine.pro

#
# Project created by QtCreator 2017-12-11T22:07:06
#
#-------------------------------------------------

QT       += core gui
QT += multimedia

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = SlotMachine
TEMPLATE = app

# The following define makes your compiler emit warnings if you use
# any feature of Qt which has been marked as deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if you use deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0


SOURCES += \
        main.cpp \
        mainwindow.cpp

HEADERS += \
        mainwindow.h \
    ritardo.h \
    roller.h

FORMS += \
        mainwindow.ui

This problem is presente only in Linux Machine.

Can anyone help me about it?

Thank you in advance.

Leandro

[SGaist]

Hi,

You should rather use QUrl::fromLocalFile.

As for your worker thread, it doesn't do what you expect. You don't have an event loop running.