VSTPluginInstance gets called twice

[MKR]

Not sure if I am doing something wrong or if this is intended as it is necessary for plugin scanning, but in VSTPluginInstance gets called twice when I host a VST2 plugin.

VSTPluginInstance (const ModuleHandle::Ptr& mh, const BusesProperties& ioConfig, Vst2::AEffect* effect,
double sampleRateToUse, int blockSizeToUse)

My code for loding it loooks like this:

juce::AudioProcessor* JUCE_CALLTYPE createPluginFilter()
{
…
juce::OwnedArrayjuce::PluginDescription pluginDescriptions;
juce::KnownPluginList plist;
juce::AudioPluginFormatManager pluginFormatManager;
pluginFormatManager.addDefaultFormats();

//here it gets called for the first time, then it is destroyed
for (int i = 0; i < pluginFormatManager.getNumFormats(); ++i)
    plist.scanAndAddFile(pluginPath, true, pluginDescriptions, *pluginFormatManager.getFormat(i));

juce::String msg;
//here it gets called for the second time
auto wrapped = pluginFormatManager.createPluginInstance(*pluginDescriptions[0], 44100.0, 512, msg);
return std::make_unique<WrapperProcessor>(std::move(wrapped)).release();  

}

Here is a thread that could be related to it:

VST2 hosting: do not instantiate VST2 effects twice

[stephenk]

It’s normal/expected and you have to deal with it. I can quickly locate several threads about it (and there are more IIRC):

PluginProcessor constructor is called twice by audio plugin host

My audio plugin [0] works… sometimes. The problem is that sometimes it gets initialised incorrectly. I run it in JUCE’s “Plugin Host.app”. When I add my VST3 plugin to the host, I notice that my PluginProcessor’s constructor gets called twice. So my private initialiseSynth() gets invoked twice, and finds that it has already been initialised before. Sometimes it survives this fine, other times I end up with segfaults when I rely on the data that I’ve constructed. Here’s the exact code of my Plu…

PluginEditor construction happens twice

Don’t mean to resurrect an old thread, but I’ve noticed this issue a few times and was always curious as to why it happened. The issue it caused for me was, when displaying a nag screen in the constructor of the pluginEditor, the user would have to dismiss it twice, as the constructor is called twice. Any good work arounds for this? I want it to be a nag screen to purchase, but I don’t want them to have to click twice.