openFrameworks | ofParameters callbacks using modern lambdas. Exclusive toggle bool's behaviour. ofParameterGroup different types filtetering / casting too.

ofApp.cpp

#include "ofApp.h"

//--------------------------------------------------------------
void ofApp::setup(){
    ofSetFrameRate(30);

    listenerMouse = ofEvents().mousePressed.newListener([this](ofMouseEventArgs&mouse) {
        ofLogNotice() << __FUNCTION__ << "mouse:"<<ofToString(mouse);
    });

    //-

    // group 1

    g1.add(f);
    g1.add(i1);
    g1.add(i2);
    g1.add(b);

    listenerGroup1 = g1.parameterChangedE().newListener([&](ofAbstractParameter&p) {
        ofLogNotice() << __FUNCTION__ << "listenerGroup1: " << p.getName();

        // get the values doing casting. we check the type first

        if(p.type() == typeid(ofParameter<float>).name() )
        {
            ofParameter<float> pm = p.cast<float>();
            ofLogNotice() << " type:float value:" <<  pm.get();
        }
        else if(p.type() == typeid(ofParameter<int>).name() )
        {
            ofParameter<int> pm = p.cast<int>();
            ofLogNotice() << " type:int value:" <<  pm.get();
        }
        else if(p.type() == typeid(ofParameter<bool>).name() )
        {
            ofParameter<bool> pm = p.cast<bool>();
            ofLogNotice() << " type:bool state: " << (pm.get() ? " TRUE":" FALSE");
        }
    });

    gui1.setup("group1");
    gui1.add(g1);

    //gui1.getFloatSlider("f").setUpdateOnReleaseOnly(true);//custom behaviour. not working..

    //-

    // group 2

    listenerGroup2.push(checkRedCircle.newListener(this, &ofApp::checkPressed));
    listenerGroup2.push(checkBlueCircle.newListener(this, &ofApp::checkPressed));
    listenerGroup2.push(checkGreenCircle.newListener(this, &ofApp::checkPressed));
    listenerGroup2.push(checkOrangeCircle.newListener(this, &ofApp::checkPressed));

    gui2.setPosition(gui1.getShape().getTopRight()+ofPoint(10,0));// layout
}

//--------------------------------------------------------------
void ofApp::draw(){
    gui1.draw();
    gui2.draw();
}

//--------------------------------------------------------------
void ofApp::checkPressed(const void * sender, bool & value){
    if(attendingEvent){
        return;
    }

    attendingEvent = true;
    auto param = (ofParameter<bool>*)sender;

    ofLogNotice() << "checkPressed: name:"
    << (param->getName()) << " "
    << (param->get() ? "TRUE":"FALSE");

    if(value == false)
    {
        // Don't let this parameter be deactivated so there's always
        // one active
        param->set(true);
    }
    else
    {
        if(param->isReferenceTo(checkRedCircle)){
            checkBlueCircle.set(false);
            checkGreenCircle.set(false);
            checkOrangeCircle.set(false);
        }
        if(param->isReferenceTo(checkBlueCircle)){
            checkRedCircle.set(false);
            checkGreenCircle.set(false);
            checkOrangeCircle.set(false);
        }
        if(param->isReferenceTo(checkGreenCircle)){
            checkRedCircle.set(false);
            checkBlueCircle.set(false);
            checkOrangeCircle.set(false);
        }
        if(param->isReferenceTo(checkOrangeCircle)){
            checkRedCircle.set(false);
            checkBlueCircle.set(false);
            checkGreenCircle.set(false);
        }
    }
    attendingEvent = false;
}

ofApp.h

#pragma once

#include "ofMain.h"
#include "ofxGui.h"

class ofApp : public ofBaseApp{

public:
    void setup();
    void draw();

    ofEventListener listenerMouse;// debug mouse clicks

    //-

    // group 1: different types params

    ofParameterGroup g1{"group1"};
    
    ofParameter<float> f{"f",0,0,1};
    ofParameter<int> i1{"i1",0,-10,10};
    ofParameter<int> i2{"i2",0,-10,10};
    ofParameter<bool> b{"b", false};

    ofEventListener listenerGroup1;

    ofxPanel gui1;

    //-

    //group 2: toggles/bool exclusive behaviour
    
    ofParameter<bool> checkRedCircle{"red", false};
    ofParameter<bool> checkBlueCircle{"blue", false};
    ofParameter<bool> checkGreenCircle{"green", false};
    ofParameter<bool> checkOrangeCircle{"orange", false};
    
    ofParameterGroup g2{
        "group2",
        checkRedCircle,
        checkBlueCircle,
        checkGreenCircle,
        checkOrangeCircle,
    };

    ofEventListeners listenerGroup2;
    void checkPressed(const void * sender, bool & value);
    bool attendingEvent;// callback blocker

    ofxPanel gui2{g2};
};