BlackBerry 10 Cascades/Qt项目中播放mp3

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以下为Cascades/Qt项目中使用。

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CascadesI/Q项目中，不能在Project的Properties里面加入library mmrndclient  和 strm。

原因：Cascades GUI应用中，使用Qt和make编译的

解决办法：

修改项目根目录下面的Qt project文件（比如 XXX.pro文件）,在

CONFIG += qt warn_on debug_and_release cascades

后面加入

LIBS   += -lmmrndclient -lstrm

参考：Linking An Object Library to an Application

其他：

在Cascades/Qt项目中，导入BB10 IDE中自带的PlayAudio例子程序。

例子程序中的头文件里面的MMR_ERROR_NONE 在编译的时候找不到相关定义，或者是语法错误。

个人学艺不精，只好暂时只好把头文件里面的ERR都暂时注释掉。

static const char *errlist[] = {
 ERR( MMR_ERROR_NONE ),

 ...

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下面是代码，根据BB10 IDE中自带PlayAudio例子C程序修改为C++ Qt程序。

#ifndef _SOUNDMANAGER_H
#define _SOUNDMANAGER_H

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>

#include <bps/bps.h>
#include <bps/audiomixer.h>
#include <bps/dialog.h>
#include <bps/navigator.h>
#include <mm/renderer.h>

#include <QtCore/qstring.h>
#include <qhash.h>

/*
 * buffer to store messages that we will display in the dialog
 */
#define MSG_SIZE 1024
static char msg[MSG_SIZE];

#if ! defined(DEFAULT_AUDIO_OUT)
    #define DEFAULT_AUDIO_OUT "audio:default"
#endif

#define COLOR_PURPLE 0xffff00ff
#define WAV_RELATIVE_PATH "/app/native/assets/farewell.mp3"

#define ERR( code ) [ code ] = #code

static const char *errlist[] = {

};
/*  Jiang TODO

 ERR( mm_error_code.MMR_ERROR_NONE),
 ERR( MMR_ERROR_UNKNOWN ),
 ERR( MMR_ERROR_INVALID_PARAMETER ),
 ERR( MMR_ERROR_INVALID_STATE ),
 ERR( MMR_ERROR_UNSUPPORTED_VALUE ),
 ERR( MMR_ERROR_UNSUPPORTED_MEDIA_TYPE ),
 ERR( MMR_ERROR_MEDIA_PROTECTED ),
 ERR( MMR_ERROR_UNSUPPORTED_OPERATION ),
 ERR( MMR_ERROR_READ ),
 ERR( MMR_ERROR_WRITE ),
 ERR( MMR_ERROR_MEDIA_UNAVAILABLE ),
 ERR( MMR_ERROR_MEDIA_CORRUPTED ),
 ERR( MMR_ERROR_OUTPUT_UNAVAILABLE ),
 ERR( MMR_ERROR_NO_MEMORY ),
 ERR( MMR_ERROR_RESOURCE_UNAVAILABLE ),
*/

#undef ERR

#define NERRS ( sizeof(errlist) / sizeof(errlist[0]) )

class SoundManager: public QObject
{
Q_OBJECT

public:

    SoundManager();
    ~SoundManager();

public slots:
    void playmp3();

};

#endif //_SOUNDMANAGER_H

#include "soundmanager.h"

void show_dialog_message(char* msg) {

}
static void mmrerror( mmr_context_t *ctxt, const char *errmsg ) {
    const mmr_error_info_t *err = mmr_error_info( ctxt );
    unsigned errcode = err->error_code;
    const char *name;
    if ( errcode >= NERRS || ( name = errlist[ errcode ] ) == NULL ) {
        name = "bad error code";
    }
    snprintf(msg, MSG_SIZE, "%s: error %d (%s)\n", errmsg, errcode, name );
    show_dialog_message(msg);
}

void SoundManager::playmp3() {
    const char *mmrname = NULL;
    const char *ctxtname = "testplayer";
    const char *audioout = NULL;
    const char *inputtype = "track";
    char cwd[PATH_MAX];
    char inputurl[PATH_MAX];
    float volume;
    int rc;
    int final_return_code = EXIT_FAILURE;
    int exit_application = 0;
    mmr_connection_t *connection = NULL;
    mmr_context_t *ctxt = NULL;

    /*
     * Before we can listen for events from the BlackBerry(R) 10 OS platform
     * services, we need to initialize the BPS infrastructure
     */
    bps_initialize();


    /*
     * Once the BPS infrastructure has been initialized we can register for
     * events from the various BlackBerry(R) 10 OS platform services. The
     * Navigator service manages and delivers application life cycle and
     * visibility events.
     * For this sample, we request Navigator events so we can track when
     * the system is terminating the application (NAVIGATOR_EXIT event). This allows
     * us to clean up application resources.
     */
    navigator_request_events(0);
    dialog_request_events(0);

    /*
     * Create and display the dialog.
     */
    //Jiang
    //create_dialog();

    getcwd(cwd, PATH_MAX);
    rc = snprintf(inputurl, PATH_MAX, "file://%s%s", cwd, WAV_RELATIVE_PATH);
    if (rc > PATH_MAX - 1)
    {
    	  show_dialog_message("File name and path too long");
          //Jiang
    	  //return 1; //fail
    	  return;
    }

    mode_t mode = S_IRUSR | S_IXUSR;
    int audio_oid; // output ID
    strm_dict_t *aoparams = NULL; // output parameters

    audioout = DEFAULT_AUDIO_OUT;

    if ( ( connection = mmr_connect( mmrname ) ) == NULL ) {
        snprintf(msg, MSG_SIZE, "mmr_connect: %s", strerror(errno));
        show_dialog_message(msg);
    } else if ( ( ctxt = mmr_context_create( connection, ctxtname, 0, mode ) ) == NULL ) {
        snprintf(msg, MSG_SIZE, "%s: %s", ctxtname, strerror(errno));
        show_dialog_message(msg);
    } else if ( audioout && ( audio_oid = mmr_output_attach( ctxt, audioout, "audio" ) ) < 0 ) {
        mmrerror( ctxt, audioout );
    } else if ( aoparams && mmr_output_parameters( ctxt, audio_oid, aoparams ) ) {
        mmrerror( ctxt, "output parameters (audio)" );
    } else if ( mmr_input_attach( ctxt, inputurl, inputtype ) < 0 ) {
        mmrerror( ctxt, inputurl );
    } else if ( mmr_play( ctxt ) < 0 ) {
        mmrerror( ctxt, "mmr_play" );
    } else {

        //3 minutes and 5 seconds is the total length of the sample song.
        rc = audiomixer_get_output_level(AUDIOMIXER_OUTPUT_SPEAKER, &volume);
        if (rc == BPS_SUCCESS) {
            snprintf(msg, MSG_SIZE, "Successfully queried the output level.\ncurrent volume is %f\n", volume);
            show_dialog_message(msg);
        } else {
            show_dialog_message("Failed to query the output level.\n");
        }

        //play for 30 seconds at normal volume
        sleep(30);

        //decrease the volume and play for 30 seconds
        audiomixer_set_output_level(AUDIOMIXER_OUTPUT_SPEAKER, volume / 2.0);
        if (rc == BPS_SUCCESS) {
            show_dialog_message("Successfully decreased the volume by half.\n");
        } else {
            show_dialog_message("Failed to decrease the volume.\n");
        }
        sleep(30);

        //set the volume to original level and play for 30 seconds
        audiomixer_set_output_level(AUDIOMIXER_OUTPUT_SPEAKER, volume);
        if (rc == BPS_SUCCESS) {
            show_dialog_message("Successfully set the volume back to original level.\n");
        } else {
            show_dialog_message("Failed to set the volume.\n");
        }
        sleep(30);

        //mute for 5 seconds
        audiomixer_set_output_mute(AUDIOMIXER_OUTPUT_SPEAKER, true);
        if (rc == BPS_SUCCESS) {
            show_dialog_message("Successfully muted.\n");
        } else {
            show_dialog_message("Failed to mute.\n");
        }
        sleep(5);

        //toggle the mute setting and play until the end
        audiomixer_toggle_output_mute(AUDIOMIXER_OUTPUT_SPEAKER);
        if (rc == BPS_SUCCESS) {
            show_dialog_message("Successfully toggled the mute setting.\n");
        } else {
            show_dialog_message("Failed to toggle the mute setting.\n");
        }
        final_return_code = EXIT_SUCCESS;
    }

    /*
     * Process Navigator events until we receive a NAVIGATOR_EXIT event.
     */
    while (!exit_application) {
        /*
         * Using a negative timeout (-1) in the call to bps_get_event(...)
         * ensures that we don't busy wait by blocking until an event is
         * available.
         */
        bps_event_t *event = NULL;
        bps_get_event(&event, -1);

        if (event) {
            /*
             * If it is a NAVIGATOR_EXIT event then set the exit_application
             * flag so the application will stop processing events, clean up
             * and exit
             */
            if (bps_event_get_domain(event) == navigator_get_domain()) {
                if (NAVIGATOR_EXIT == bps_event_get_code(event) && (final_return_code == EXIT_SUCCESS)) {
                    mmr_stop( ctxt );             // Not really necessary -- mmr_input_detach() would take care of this
                    mmr_input_detach( ctxt );     // Not really necessary -- mmr_context_destroy()  would take care of this
                    mmr_context_destroy( ctxt );  // Not really necessary -- mmr_disconnect() would take care of this
                    mmr_disconnect( connection ); // Not really necessary -- exiting would take care of this
                    exit_application = 1;
                }
            }
        }
    }

   /*  * Clean up the BPS infrastructure and exit
     */
    bps_shutdown();

    //Jiang
    //return final_return_code;
    return;
}


SoundManager::SoundManager()
{
}

SoundManager::~SoundManager()
{
}