How to get a bang when Push 2 is turned on?

I periodically poll the control_surfaces object for changes and this works very well. This object will do that on a bang, or if you set the @auto part it will do it on a timer. It will output the id of Push or 0 if it doesn't exist. That way you get connect and disconnect:

And here is a javascript version of the same concept. You can pass callback functions in as options when you create the object like onPushConnected and onPushDisconnected:

var pushAPI = null; // global ref

// called once by [live.thisdevice]
function live_api_init() {
    if(pushAPI.PKLiveAPI.bInit) {
        return;
    }
    log('live_api_init()');
    pushAPI.PKLiveAPI.bInit = true;
    pushAPI.live_api_init();
}

function Push(options) {

    pushAPI = this; // retain reference at least for timers, but also for glboal access

    options = typeof options !== 'undefined' ? options : {};

    this.bLiveAPIInit = false;
    this.live_api_init = function() {
        if(this.bLiveAPIInit) {
            return;
        }
        if(options.onLiveAPIInit) {
            options.onLiveAPIInit();
        }
        this.bLiveAPIInit = true;
        this.poll();
    };

    this.poll = function() {
        if(this.bLiveAPIInit == false) {
            return;
        }
        var exists = false;
          for(var i=0; i < 6; i++) {
                var api = new LiveAPI("control_surfaces " + i);
            if(api.type.indexOf('Push') == 0) { // 'Push' || 'Push2'
                var thisId = this.api != null ? this.api.id : null;
                if(this.api && this.api.id == api.id) {
                    exists = true;
                } else if(!this.api || this.api.id != api.id) {
                    this.api = api;
                    options.api = api;
                    exists = true;
                    if(options.onPushConnected) {
                        options.onPushConnected();
                    }
                }
            }
          }
        if(!exists && this.api) {
            this.api = null;
            if(options.onPushDisconnected) {
                options.onPushDisconnected();
            }
        }
    },

    this.init = function() {
        this.api = null;
        this.dead = false;

        // just check a little time after the live api might be initialized
        // in case we are in js dev mode and no [live.thisdevice] bang is coming.
        // if a [live.thisdevice] bang already came then running it again won't hurt.
        // this.pollCheck = new Task(function() {
        //     this.poll();
        //     if(this.bPolling == false && this.pollRepeat) {
        //         this.pollRepeat.repeat();
        //         this.bPolling = true;
        //     }
        // }, this);
        // this.pollCheck.schedule(1500);
        
        // the regular polling task, started above
        this.pollRepeat = new Task(this.poll, this);
        this.pollRepeat.interval = 1000;
        this.pollRepeat.repeat();

        // store in a global to recall if [live.thisdevice] sent bang
        // before script is re-loaded with autowatch.
        if(this.PKLiveAPI.bInit === undefined) {
            this.PKLiveAPI.bInit = false;
        } else if(this.PKLiveAPI.bInit) {
            log('Push.init: calling live_api_init');
            this.live_api_init();
        }

        this.bPolling = false;
    },
    
    this.PKLiveAPI = new Global('PKLiveAPI');

    this.initTask = new Task(function() {
        this.init();
    }, this);
    this.initTask.schedule(0); // defer to avoid null 'app' references in api callbacks

    return options;
}

var push = new Push({
onPushConnected: function() {},
onPushDisconnected: function() {}
});