Why use QAudioOutput play audio is fail?

[tiaoweiliao]

hi , all.

i use QAudioInput record sound.

input code is :

void start(){
    file = new QFile("C:/audiorecord.raw");
    file->open(QIODevice::WriteOnly | QIODevice::Truncate);
    //set format
    QAudioFormat format;
    format.setSampleRate(8000);
    format.setChannelCount(1);
    format.setSampleSize(32);
    format.setCodec("audio/pcm");
    format.setByteOrder(QAudioFormat::LittleEndian);
    format.setSampleType(QAudioFormat::Float);
 
    input = new QAudioInput(format, this);//input is QAudioInput * input;
    input->start(file);
}
 
void finish(){
    input->stop();
    file->close();
}

void start(){
    file = new QFile("C:/audiorecord.raw");
    file->open(QIODevice::WriteOnly | QIODevice::Truncate);
    //set format
    QAudioFormat format;
    format.setSampleRate(8000);
    format.setChannelCount(1);
    format.setSampleSize(32);
    format.setCodec("audio/pcm");
    format.setByteOrder(QAudioFormat::LittleEndian);
    format.setSampleType(QAudioFormat::Float);
    
    input = new QAudioInput(format, this);//input is QAudioInput * input;
    input->start(file);
}

void finish(){
    input->stop();
    file->close();
}

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write data to successful , call function "void finish()" later.

void play(){
    file->setFileName("C:/audiorecord.raw");
    file->open(QIODevice::ReadOnly);
 
    QAudioFormat format;
    format.setSampleRate(8000);
    format.setChannelCount(1);
    format.setSampleSize(32);
    format.setCodec("audio/pcm");
    format.setByteOrder(QAudioFormat::LittleEndian);
    format.setSampleType(QAudioFormat::Float);
 
    output = new QAudioOutput(format,0);
    output->start(file);
}

void play(){
    file->setFileName("C:/audiorecord.raw");
    file->open(QIODevice::ReadOnly);

    QAudioFormat format;
    format.setSampleRate(8000);
    format.setChannelCount(1);
    format.setSampleSize(32);
    format.setCodec("audio/pcm");
    format.setByteOrder(QAudioFormat::LittleEndian);
    format.setSampleType(QAudioFormat::Float);

    output = new QAudioOutput(format,0);
    output->start(file);
}

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if the program not restarted , in "start()" later call function "play()" is no problem, Play success.

but if program restarted , call play() is program crash.

What's the problem?

I will very much appreciate it.

[anda_skoa]

play() accesses "file" without checking it is a valid pointer.
start() creates the file, so play() works after start().

Cheers,
_

[tiaoweiliao]

play() accesses "file" without checking it is a valid pointer.
start() creates the file, so play() works after start().

Cheers,
_

thank you.

oh!!! sorry , a very stupid mistake , I was too careless.