xamarin.forms - Reactive Extensions for nested objects in Exrin VisualState -

i'm trying enable button bounded when binded property nested field entered, button disabled when properties filled data. should change?

this base visual state

public class basevisualstate : exrin.framework.visualstate { public basevisualstate() : this(null) { }  public basevisualstate(ibasemodel i_model) : base(i_model) { propertyobservable = observable.fromeventpattern(                 (eventhandler<propertychangedeventargs> i_event) => new propertychangedeventhandler(i_event),                 i_eventchanged => this.propertychanged += i_eventchanged,                 i_eventchanged => this.propertychanged -= i_eventchanged);         }          public iobservable<eventpattern<propertychangedeventargs>> propertyobservable { get; private set; }     } 

and visual state is

public class beaconaddvisualstate : basevisualstate     {         private readonly ibeaconaddmodel r_model;          public beaconaddvisualstate(ibeaconaddmodel i_model)             : base(i_model)         {             r_model = i_model;         }          [binding(bindingtype.twoway)]         public beacon beacon         {                         {                 return get<beacon>();             }              set             {                 set(value);             }         }          public override async void init()         {             beacon = new beacon();         }     } 

the beacon class notifies on property changed

public class beacon : document<guid>, inotifypropertychanged     {         private string m_proximityuuid;         private int? m_major;         private int? m_minor;          [required]         public string proximityuuid         {                         {                 return m_proximityuuid;             }              set             {                 if(m_proximityuuid != value)                 {                     m_proximityuuid = value;                     notifypropertychanged();                 }             }         }          [required]         public int? major         {                         {                 return m_major;             }              set             {                 if (m_major != value)                 {                     m_major = value;                     notifypropertychanged();                 }             }         }          [required]         public int? minor         {                         {                 return m_minor;             }              set             {                 if (m_minor != value)                 {                     m_minor = value;                     notifypropertychanged();                 }             }         }          public event propertychangedeventhandler propertychanged;          // method called set accessor of each property.         // callermembername attribute applied optional propertyname         // parameter causes property name of caller substituted argument.         private void notifypropertychanged([callermembername] string i_propertyname = "")         {             if (propertychanged != null)             {                 propertychanged(this, new propertychangedeventargs(i_propertyname));             }         }     } 

and viewmodel

public class beaconaddviewmodel : baseauthviewmodel     {         private readonly ibeaconaddmodel r_model;         private readonly idisposable r_subscription;          public beaconaddviewmodel(ibeaconaddmodel i_model)             : base(new beaconaddvisualstate(i_model))         {             r_model = i_model;             r_subscription = state.propertyobservable.where(                 i_arg => i_arg.eventargs.propertyname == nameof(state.beacon.proximityuuid)                          || i_arg.eventargs.propertyname == nameof(state.beacon.major) || i_arg.eventargs.propertyname == nameof(state.beacon.minor)).subscribe(                 i_arg =>                     {                         addcommand.oncanexecutechanged();                     });         }          private beaconaddvisualstate state => visualstate beaconaddvisualstate;          public override task onnavigated(object i_args)         {             return base.onnavigated(i_args);         }          public irelaycommand addcommand         {                         {                 return getcommand(                     () =>                         {                             return new relaycommand(                                 async (i_parameter) =>                                     {                                         await r_model.addbeacon(i_parameter beacon);                                         await navigationservice.navigate("beacons");                                     }, (i_obj) => !string.isnullorempty(state.beacon.proximityuuid) && state.beacon.major.hasvalue && state.beacon.minor.hasvalue;                         });             }         }          public override void disposing()         {             base.disposing();             r_subscription?.dispose();         }     } 

the problem here trigger inpc inside beacon class, basevisualstate looking @ whether beacon (the object itself) changing.

hence either have bring properties outside of beacon, directly visualstate, or relay inpc event.

e.g. in set of beacon do

var beacon = value; set(value); value.onpropertychanged += (s,e) => { onpropertychanged(nameof(beacon)); } 

that mean, each time property in beacon changed, beacon class has changed, , trigger inpc visualstate.

note: make sure event disposed on, when it's reset. mean not doing in anon func have shown above, doing += , tabbing create method.