"QAudioDeviceInfo::availableDevices(QAudio::AudioOutput)" takes a lot of time.

GimInGZ

When I use it directly in the main thread, UI will stuck by it for a long time.
What should I do?

Truly grateful for your help.

code:

#include <QApplication>
#include <QDateTime>
#include <QAudioDeviceInfo>
#include <QDebug>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    QTime time;
    time.start();
    QAudioDeviceInfo::availableDevices(QAudio::AudioOutput);
    qInfo() << time.restart();

    QAudioDeviceInfo::availableDevices(QAudio::AudioOutput);
    qInfo() << time.restart();

    QAudioDeviceInfo::availableDevices(QAudio::AudioOutput);
    qInfo() << time.restart();

    return a.exec();
}

output:

Qt version：
Qt 5.13.0 MSVC2017 32bit

OS: Windows 10 (10.0.18362)

SGaist

Hi and welcome to devnet,

What kind of devices do you have on your machine ? How many of them ?
Note that QtMultimedia uses platform specific APIs in its backends so it might be something related to your Windows installation.

GimInGZ

Hi. thank for your reply.
I dont know what happen……I haven't do anythings but it work fine now.😰

I have these devices on my machine.

output devices:
Speakers(USB Audio Device)
Speakers/Headset(Realtek High Definition Audio)

input devices:
Microphone(USB Audio Device)
Microphone(Realtek USB2.0 MIC)
Stereo Mixer(Realtek High Definition Audio)
Microphone Array(Realtek High Definition Audio)

SGaist

You may have just had a system glitch at some point. Maybe a virus scanner or something like that running while you were hacking and hogging resources.