I need help with listbox

General JUCE discussion
1

Hello to all. I wrote a player that has a playlist. All functions work perfectly in Windows and Mac OS, but in Mac OS there is one problem. Each time before starting a file, the listbox checks for the presence of files, and if the playlist contains files with the .mp3 extension, then there is a significant delay before playback. If there are 17 files in the playlist, the delay is more than 4 seconds in MacBook Pro 2020 (Ventura OS) and 7 seconds in MacBook Pro 2012 (Catalina OS). The delay increases according to the number of files. On Windows, playback of these same files occurs instantly. Is there a way to avoid such a delay, or does Mac OS not like .mp3 so much?
Below is the file verification code:

void GUI::ListBoxComponent::checkPlaylist()
{
    Array<File> files;
    AudioFormatManager audioFormatManager;
    audioFormatManager.registerBasicFormats();
    String audioFormats = audioFormatManager.getWildcardForAllFormats();
    #if JUCE_WINDOWS
    File::getSpecialLocation (File::userDesktopDirectory).findChildFiles (files, File::findFiles, true, audioFormats);
    #else
    parseWinPathForMac ();
    #endif
    totaltimeseconds = 0.0;
    if (oscSender.connect (ip, portNumber))
        oscSender.send ("/" + ipHome + "/clear", 1);

    for(int i = 0; i < songList.size(); i++)
    {
	    File file (filePath.getReference(i));
	    #if JUCE_MAC
	    String macPath = filePath.getReference(i);
	    StringArray arr;
	    arr.addTokens (macPath, "/", "");
        if (arr[3] == "Desktop")
	        File::getSpecialLocation (File::userDesktopDirectory).findChildFiles (files, File::findFiles, true, audioFormats);
        #endif
        for (int j = 0; j < files.size(); j++)
        {
            if (file.getFileName() == files[j].getFileName() && !file.existsAsFile())
            {
                filePath.set (i, files[j].getFullPathName());
                file = filePath.getReference(i);
            }
        }
        
        AudioTransportSource audioSource;
        auto* reader = audioFormatManager.createReaderFor (file);
        String a = file.getFileNameWithoutExtension();
        String b;
        if (reader)
        {
            auto newSource = std::make_unique<AudioFormatReaderSource> (reader, true);
            audioSourceReader.reset (newSource.release());
            audioSource.setSource(audioSourceReader.get());
             
            RelativeTime totalLength (audioSource.getLengthInSeconds());
      
            auto hours = ((int) totalLength.inHours()) % 60;
            auto minutes = ((int) totalLength.inMinutes()) % 60;
            auto seconds = ((int) totalLength.inSeconds()) % 60;
            auto totalLengthString = String::formatted ("%02d:%02d", minutes, seconds);
            auto totalLengthStringH = String::formatted ("%01d:%02d:%02d", hours, minutes, seconds);
                
            if (audioSource.getLengthInSeconds() < 3600)
            {
                songDuration.getReference(i) = totalLengthString;
                b = totalLengthString;
            }
            else
            {
                songDuration.getReference(i) = totalLengthStringH;
                b = totalLengthStringH;
            }

            //============== Full PlayList Time ===============
            totaltimeseconds += (double)reader->lengthInSamples / reader->sampleRate;
            RelativeTime totalListLength (totaltimeseconds);            
            
            auto hoursFull = ((int) totalListLength.inHours()) % 60;
            auto minutesFull = ((int) totalListLength.inMinutes()) % 60;
            auto secondsFull = ((int) totalListLength.inSeconds()) % 60;
            auto totalListLengthString = String::formatted ("%02d:%02d", minutesFull, secondsFull);
            auto totalListLengthStringH = String::formatted ("%01d:%02d:%02d", hoursFull, minutesFull, secondsFull);
            
            if (totaltimeseconds < 3600)
                infoLblTime = totalListLengthString;
            else
                infoLblTime = totalListLengthStringH;
            //==================================================
            if (infoLblTime.isEmpty())
            {
                infoTextLbl.setText ("0 songs | 00:00", dontSendNotification);
                infoLbl.setTooltip ("0 songs | 00:00");
            }
            else
            {
                infoLblAmount = static_cast<String>(songList.size());
                infoTextLbl.setText (infoLblAmount + " songs | " + infoLblTime, dontSendNotification);
                infoLbl.setTooltip (infoLblAmount + " songs | " + infoLblTime);
            }
        }    
        else
        {
            songDuration.getReference(i) = "__:__";
            b = "__:__";
        }
        if (oscSender.connect (ip, portNumber))
            oscSender.send ("/" + ipHome + "/fileName", a, b, pointLabel.getReference(i), playingSongIndex);
    }
}

If you remove the readability check, then, naturally, the delay disappears. The reason for this is
auto* reader = audioFormatManager.createReaderFor (file);.
Can anyone tell me how to make life easier for the listbox?
Thanks in advance for your valuable advice.

2

Of course, there is a way to check not all files in the playlist during playback, but only the file being played, but you still want to update all the information every time. Is there any other way to check the list on Mac OS?

3

Check the number of “knownFormats” on both Windows and MacOS by putting a breakpoint in AudioFormatManager::createReaderFor() and inspecting the knownFormats array … this might give you a hint. You might be better off just using “::findFormatForFileExtension()” and doing your own localCreateReader() method …

(Disclaimer: this is glib advice, I haven’t done any of the above!)

4

Thank you.
I’ll try. Although, as I understand it, if I exclude .mp3 from the verification rule, I will not be able to upload these files to the playlist.

5

M1 Big Sur does not have this problem.