IMidiLearn Class Reference

MIDI Learn interface: Vst::IMidiLearn. More...

#include <ivstmidilearn.h>

Inheritance diagram for IMidiLearn:

Public Member Functions
virtual tresult	onLiveMIDIControllerInput (int32 busIndex, int16 channel, CtrlNumber midiCC)=0
	Called on live input MIDI-CC change associated to a given bus index and MIDI channel.
Public Member Functions inherited from FUnknown
virtual tresult	queryInterface (const TUID _iid, void **obj)=0
virtual uint32	addRef ()=0
virtual uint32	release ()=0

Static Public Attributes
static const FUID	iid
Static Public Attributes inherited from FUnknown
static const FUID	iid

Detailed Description

MIDI Learn interface: Vst::IMidiLearn.

• [plug imp]
• [extends IEditController]
• [released: 3.6.12]
• [optional]

If this interface is implemented by the edit controller, the host will call this method whenever there is live MIDI-CC input for the plug-in. This way, the plug-in can change its MIDI-CC parameter mapping and inform the host via the IComponentHandler::restartComponent with the kMidiCCAssignmentChanged flag. Use this if you want to implement custom MIDI-Learn functionality in your plug-in.

//------------------------------------------------
// in MyController class declaration
class MyController : public Vst::EditController, public Vst::IMidiLearn
{
    // ...
    //--- IMidiLearn ---------------------------------
    tresult PLUGIN_API onLiveMIDIControllerInput (int32 busIndex, int16 channel,
                                                  CtrlNumber midiCC) SMTG_OVERRIDE;
    // ...

    OBJ_METHODS (MyController, Vst::EditController)
    DEFINE_INTERFACES
        // ...
        DEF_INTERFACE (Vst::IMidiLearn)
    END_DEFINE_INTERFACES (Vst::EditController)
    //...
}

//------------------------------------------------
// in mycontroller.cpp
#include "pluginterfaces/vst/ivstmidilearn.h

namespace Steinberg {
    namespace Vst {
        DEF_CLASS_IID (IMidiLearn)
    }
}

//------------------------------------------------------------------------
tresult PLUGIN_API MyController::onLiveMIDIControllerInput (int32 busIndex, 
                            int16 channel, CtrlNumber midiCC)
{
    // if we are not in doMIDILearn (triggered by a UI button for example) 
    // or wrong channel then return
    if (!doMIDILearn || busIndex != 0 || channel != 0 || midiLearnParamID == InvalidParamID)
        return kResultFalse;

    // adapt our internal MIDICC -> parameterID mapping
    midiCCMapping[midiCC] = midiLearnParamID;

    // new mapping then inform the host that our MIDI assignment has changed
    if (auto componentHandler = getComponentHandler ())
    {
        componentHandler->restartComponent (kMidiCCAssignmentChanged);
    }
    return kResultTrue;
}

Member Function Documentation

virtual tresult onLiveMIDIControllerInput ( int32  busIndex, int16  channel, CtrlNumber  midiCC  )

pure virtual

Called on live input MIDI-CC change associated to a given bus index and MIDI channel.

Member Data Documentation

const FUID iid

static