[JUCE API] Load Preset

The XML file needs to be imported and converted into parameters

case IdComboBoxPreset::Load:
                    {
                        DBG("Load");
                        mPresetManager.loadXmlPreset(file);
                        break;
                    }

void MyPresetManager::loadXmlPreset(const juce::File& inFileXml) noexcept
{
	std::unique_ptr<juce::XmlElement> xml = juce::XmlDocument::parse(inFileXml);
}

First, the selected inFile object from the file explorer needs to be converted into XML. In this case, the parse() function should be used.

juce::FIile inFile ?

juce::File doesn't actually contain the file itself. It just holds the file's path and name. So whether you're saving or loading something through the file explorer, you can still use it to handle the result data.

const juce::ValueTree inState = juce::ValueTree::fromXml(*xml);

This is process of converting from xml to valuetree(parameter). It is important to pass a pointer to a parameter.

    if(inState.getType() == mApvts.state.getType())
    {
        mApvts.replaceState(inState);
    }

At this, getType() return as an juce::Identifier. It indicates the ID of ValuTree. The replaceState() method in apvts updates the parameter.