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[3.6.0] Preset Meta-Information

On this page:

• Introduction
• Example

Introduction

Meta attributes of a stream: Vst::IStreamAttributes.

• [host imp]
• [extends IBStream]
• [released: 3.6.0]
• [optional]

Interface to access preset meta information from stream, used, for example, in setState in order to inform the plug-in about the current context in which the preset loading occurs(Project context or Preset load (see StateType)) or used to get the full file path of the loaded preset (if available).

Example

#include "pluginterfaces/base/ustring.h"
#include "pluginterfaces/vst/vstpresetkeys.h"
// ...
 
tresult PLUGIN_API MyPluginProcessor::setState (IBStream* state)
{
    if (auto stream = Steinberg::U::cast<IStreamAttributes> (state))
    {
        IAttributeList* list = stream->getAttributes ();
        if (list)
        {
            // get the current type (project/Default..) of this state
            String128 string;
            if (list->getString (PresetAttributes::kStateType, string, 128 * sizeof (TChar)) == kResultTrue)
            {
                UString128 tmp (string);
                char ascii[128];
                tmp.toAscii (ascii, 128);
                if (!strncmp (ascii, StateType::kProject, strlen (StateType::kProject)))
                {
                    // we are in project loading context...
                }
            }
 
            // get the full file path of this state
            TChar fullPath[1024];
            if (list->getString (PresetAttributes::kFilePathStringType, fullPath, 1024 * sizeof (TChar)) == kResultTrue)
            {
                // here we have the full path ...
            }
        }
    }
    //...read the state here.....
    return kResultTrue;
}