var setListeners = func {

    setlistener('/instrumentation/nav/nav-id',

            func (n) {

                var val = n.getValue();

                foreach (var c; keys(flightdeck))

                    flightdeck[c].display.updateNAV({'nav-id': 1, val: val});

            }, 1, 2);

    setlistener('/instrumentation/nav[1]/nav-id',

            func (n) {

                var val = n.getValue();

                foreach (var c; keys(flightdeck))

                    flightdeck[c].display.updateNAV({'nav-id': 2, val: val});

            }, 1, 2);

   # keep this listener as long as the code is to heavy to be modified in multiple places

    setlistener('/instrumentation/zkv1000/afcs/selected-alt-ft',

            func (n) {

                var val = n.getValue();

                if (val != nil)

                    foreach (var c; keys(flightdeck))

                        if (flightdeck[c].role == 'PFD') {

                            if (! flightdeck[c].display.screenElements['SelectedALT'].getVisible()) {

                                flightdeck[c].display.screenElements['SelectedALT'].show();

                                flightdeck[c].display.screenElements['SelectedALT-text'].show();

                                flightdeck[c].display.screenElements['SelectedALT-symbol'].show();

                                flightdeck[c].display.screenElements['SelectedALT-bug'].show();

                                flightdeck[c].display.screenElements['SelectedALT-bg'].show();

                            }

                            flightdeck[c].display.updateSelectedALT();

                        }

            }, 0, 2);

    setlistener('/gear/gear/wow',

            func foreach (var c; keys(flightdeck))

                if (flightdeck[c].role == 'PFD')

                    flightdeck[c].display.updateXPDR(),

            0, 0);

    setlistener('/instrumentation/altimeter/setting-inhg',

            func foreach (var c; keys(flightdeck))

                if (flightdeck[c].role == 'PFD')

                    flightdeck[c].display.updateBARO(), 0, 2);

}

var deviceClass = {

    new: func (name) {

        var m = { parents: [ deviceClass ] };

        m.name = name;

        m.role = substr(name, 0, 3);

        m.node = zkv.getNode(name, 1);

        m.data = {};

        foreach (var v; ['Vx', 'Vy', 'Vr', 'Vglide'])

            m.data[v ~ '-visible'] = 1;

        foreach (var v; ['screen-object', 'screen-view', 'screen-size'])

            m.data[v] = getprop('/instrumentation/zkv1000/' ~ name ~ '/' ~ v);

        m.display  = displayClass.new(m);

        m.display.showInitProgress(m.name);

        m.softkeys = softkeysClass.new(m);

        m.buttons  = buttonsClass.new(m);

        m.knobs    = knobsClass.new(m);

        m.display.loadsvg();

        m.display.loadGroup({

            hide : [

                'Failures',

                'SoftKeysTexts',

                'PFD-Widgets', 

                'COMM',

                'XPDR-TIME', 

                'NAV',

                'FlightInstruments', 

                'VDI',

                'OMI',

            ],

            clip : 'PitchScale',

        });

        m.windows  = pageClass.new(m);

        zkv.getNode(m.name ~ '-init').setIntValue(0);

        setprop('/instrumentation/zkv1000/' ~ m.name ~ '/status', 1);

        msg(m.name ~ ' switched on!');

        return m;

    },

};

var powerOn = func {

    foreach (var freq; keys(data.timers))

        data.timers[freq].start();

    foreach (var name; keys(flightdeck))

        if (zkv.getNode(name) != nil)

#            thread.newthread(func {

                flightdeck[name] = deviceClass.new(name);

#            });

    settimer(setListeners, 5);

}