static IObservedChange <object, object> observedChangeFor(string propertyName, IObservedChange <object, object> sourceChange)
{
var p = new ObservedChange <object, object>()
{
Sender = sourceChange.Value,
PropertyName = propertyName,
};
if (sourceChange.Value == null)
{
return(p);
}
return(p.fillInValue());
}
/// <summary>
/// WhenAny allows you to observe whenever one or more properties on an
/// object have changed, providing an initial value when the Observable
/// is set up, unlike ObservableForProperty(). Use this method in
/// constructors to set up bindings between properties that also need an
/// initial setup.
/// </summary>
public static IObservable <TRet> WhenAnyDynamic <TSender, TRet>(this TSender This,
string[] property1,
Func <IObservedChange <TSender, object>, TRet> selector)
{
var slot1 = new ObservedChange <TSender, object>()
{
Sender = This,
PropertyName = String.Join(".", property1),
};
object slot1Value = default(object); slot1.TryGetValue(out slot1Value); slot1.Value = slot1Value;
IObservedChange <TSender, object> islot1 = slot1;
return(Observable.Create <TRet>(subject => {
subject.OnNext(selector(islot1));
return Observable.Merge(This.ObservableForProperty(property1).Do(x => { lock (slot1) { islot1 = x.fillInValue(); } }).Select(x => selector(islot1))).Subscribe(subject);
}));
}
/// <summary>
/// WhenAny allows you to observe whenever one or more properties on an
/// object have changed, providing an initial value when the Observable
/// is set up, unlike ObservableForProperty(). Use this method in
/// constructors to set up bindings between properties that also need an
/// initial setup.
/// </summary>
public static IObservable <TRet> WhenAny <TSender, TRet, T1>(this TSender This,
Expression <Func <TSender, T1> > property1,
Func <IObservedChange <TSender, T1>, TRet> selector)
{
var slot1 = new ObservedChange <TSender, T1>()
{
Sender = This,
PropertyName = String.Join(".", Reflection.ExpressionToPropertyNames(property1)),
};
T1 slot1Value = default(T1); slot1.TryGetValue(out slot1Value); slot1.Value = slot1Value;
IObservedChange <TSender, T1> islot1 = slot1;
return(Observable.Create <TRet>(subject => {
subject.OnNext(selector(islot1));
return Observable.Merge(This.ObservableForProperty(property1).Do(x => { lock (slot1) { islot1 = x.fillInValue(); } }).Select(x => selector(islot1))).Subscribe(subject);
}));
}
/// <summary>
/// WhenAny allows you to observe whenever one or more properties on an
/// object have changed, providing an initial value when the Observable
/// is set up, unlike ObservableForProperty(). Use this method in
/// constructors to set up bindings between properties that also need an
/// initial setup.
/// </summary>
public static IObservable <TRet> WhenAny <TSender, TRet, T1, T2, T3>(this TSender This,
Expression <Func <TSender, T1> > property1,
Expression <Func <TSender, T2> > property2,
Expression <Func <TSender, T3> > property3,
Func <IObservedChange <TSender, T1>, IObservedChange <TSender, T2>, IObservedChange <TSender, T3>, TRet> selector)
where TSender : IReactiveNotifyPropertyChanged
{
var slot1 = new ObservedChange <TSender, T1>()
{
Sender = This,
PropertyName = String.Join(".", RxApp.expressionToPropertyNames(property1)),
};
T1 slot1Value = default(T1); slot1.TryGetValue(out slot1Value); slot1.Value = slot1Value;
IObservedChange <TSender, T1> islot1 = slot1;
var slot2 = new ObservedChange <TSender, T2>()
{
Sender = This,
PropertyName = String.Join(".", RxApp.expressionToPropertyNames(property2)),
};
T2 slot2Value = default(T2); slot2.TryGetValue(out slot2Value); slot2.Value = slot2Value;
IObservedChange <TSender, T2> islot2 = slot2;
var slot3 = new ObservedChange <TSender, T3>()
{
Sender = This,
PropertyName = String.Join(".", RxApp.expressionToPropertyNames(property3)),
};
T3 slot3Value = default(T3); slot3.TryGetValue(out slot3Value); slot3.Value = slot3Value;
IObservedChange <TSender, T3> islot3 = slot3;
return(Observable.Create <TRet>(subject => {
subject.OnNext(selector(islot1, islot2, islot3));
return Observable.Merge(
This.ObservableForProperty(property1).Do(x => { lock (slot1) { islot1 = x.fillInValue(); } }).Select(x => selector(islot1, islot2, islot3)),
This.ObservableForProperty(property2).Do(x => { lock (slot2) { islot2 = x.fillInValue(); } }).Select(x => selector(islot1, islot2, islot3)),
This.ObservableForProperty(property3).Do(x => { lock (slot3) { islot3 = x.fillInValue(); } }).Select(x => selector(islot1, islot2, islot3))
).Subscribe(subject);
}));
}
public static bool TryGetAllValuesForPropertyChain(out IObservedChange <object, object>[] changeValues, object current, string[] propNames)
{
int currentIndex = 0;
changeValues = new IObservedChange <object, object> [propNames.Length];
foreach (var propName in propNames.SkipLast(1))
{
if (current == null)
{
changeValues[currentIndex] = null;
return(false);
}
var box = new ObservedChange <object, object> {
Sender = current, PropertyName = propName
};
current = GetValueFetcherOrThrow(current.GetType(), propName)(current);
box.Value = current;
changeValues[currentIndex] = box;
currentIndex++;
}
if (current == null)
{
changeValues[currentIndex] = null;
return(false);
}
changeValues[currentIndex] = new ObservedChange <object, object> {
Sender = current,
PropertyName = propNames.Last(),
Value = GetValueFetcherOrThrow(current.GetType(), propNames.Last())(current)
};
return(true);
}
static void subscribeToExpressionChain <TSender, TValue>(
TSender origSource,
string origPath,
object source,
LinkedListNode <string> propertyNames,
LinkedListNode <IDisposable> subscriptions,
bool beforeChange,
Subject <IObservedChange <TSender, TValue> > subject
)
{
var current = propertyNames;
var currentSub = subscriptions;
object currentObj = source;
ObservedChange <TSender, TValue> obsCh;
while (current.Next != null)
{
Func <object, object> getter = null;
if (currentObj != null)
{
getter = Reflection.GetValueFetcherForProperty(currentObj.GetType(), current.Value);
if (getter == null)
{
subscriptions.List.Where(x => x != null).ForEach(x => x.Dispose());
throw new ArgumentException(String.Format("Property '{0}' does not exist in expression", current.Value));
}
var capture = new { current, currentObj, getter, currentSub };
var toDispose = new IDisposable[2];
var valGetter = new ObservedChange <object, TValue>()
{
Sender = capture.currentObj,
PropertyName = buildPropPathFromNodePtr(capture.current),
Value = default(TValue),
};
TValue prevVal = default(TValue);
bool prevValSet = valGetter.TryGetValue(out prevVal);
toDispose[0] = notifyForProperty(currentObj, capture.current.Value, true).Subscribe(x => {
prevValSet = valGetter.TryGetValue(out prevVal);
});
toDispose[1] = notifyForProperty(currentObj, capture.current.Value, false).Subscribe(x => {
subscribeToExpressionChain(origSource, origPath, capture.getter(capture.currentObj), capture.current.Next, capture.currentSub.Next, beforeChange, subject);
TValue newVal;
if (!valGetter.TryGetValue(out newVal))
{
return;
}
if (prevValSet && EqualityComparer <TValue> .Default.Equals(prevVal, newVal))
{
return;
}
obsCh = new ObservedChange <TSender, TValue>()
{
Sender = origSource,
PropertyName = origPath,
Value = default(TValue),
};
TValue obsChVal;
if (obsCh.TryGetValue(out obsChVal))
{
obsCh.Value = obsChVal;
subject.OnNext(obsCh);
}
});
currentSub.Value = Disposable.Create(() => { toDispose[0].Dispose(); toDispose[1].Dispose(); });
}
current = current.Next;
currentSub = currentSub.Next;
currentObj = getter != null?getter(currentObj) : null;
}
if (currentSub.Value != null)
{
currentSub.Value.Dispose();
}
if (currentObj == null)
{
return;
}
var propName = current.Value;
var finalGetter = Reflection.GetValueFetcherForProperty(currentObj.GetType(), current.Value);
currentSub.Value = notifyForProperty(currentObj, propName, beforeChange).Subscribe(x => {
obsCh = new ObservedChange <TSender, TValue>()
{
Sender = origSource,
PropertyName = origPath,
Value = (TValue)finalGetter(currentObj),
};
subject.OnNext(obsCh);
});
}
static void subscribeToExpressionChain <TSender, TValue>(
TSender origSource,
string origPath,
object source,
LinkedListNode <string> propertyNames,
LinkedListNode <IDisposable> subscriptions,
bool beforeChange,
Subject <IObservedChange <TSender, TValue> > subject
)
{
var current = propertyNames;
var currentSub = subscriptions;
object currentObj = source;
PropertyInfo pi = null;
ObservedChange <TSender, TValue> obsCh;
while (current.Next != null)
{
pi = RxApp.getPropertyInfoForProperty(currentObj.GetType(), current.Value);
if (pi == null)
{
subscriptions.List.Where(x => x != null).ForEach(x => x.Dispose());
throw new ArgumentException(String.Format("Property '{0}' does not exist in expression", current.Value));
}
var notifyObj = wrapInpcObjectIfNeeded(currentObj);
if (notifyObj != null)
{
var capture = new { current, currentObj, pi, currentSub };
var toDispose = new IDisposable[2];
var valGetter = new ObservedChange <object, TValue>()
{
Sender = capture.currentObj,
PropertyName = buildPropPathFromNodePtr(capture.current),
Value = default(TValue),
};
TValue prevVal = default(TValue);
bool prevValSet = valGetter.TryGetValue(out prevVal);
toDispose[0] = notifyObj.Changing.Where(x => x.PropertyName == capture.current.Value).Subscribe(x => {
prevValSet = valGetter.TryGetValue(out prevVal);
});
toDispose[1] = notifyObj.Changed.Where(x => x.PropertyName == capture.current.Value).Subscribe(x => {
subscribeToExpressionChain(origSource, origPath, capture.pi.GetValue(capture.currentObj, null), capture.current.Next, capture.currentSub.Next, beforeChange, subject);
TValue newVal;
if (!valGetter.TryGetValue(out newVal))
{
return;
}
if (prevValSet && EqualityComparer <TValue> .Default.Equals(prevVal, newVal))
{
return;
}
obsCh = new ObservedChange <TSender, TValue>()
{
Sender = origSource,
PropertyName = origPath,
Value = default(TValue),
};
TValue obsChVal;
if (obsCh.TryGetValue(out obsChVal))
{
obsCh.Value = obsChVal;
subject.OnNext(obsCh);
}
});
currentSub.Value = Disposable.Create(() => { toDispose[0].Dispose(); toDispose[1].Dispose(); });
}
current = current.Next;
currentSub = currentSub.Next;
currentObj = pi.GetValue(currentObj, null);
}
var finalNotify = wrapInpcObjectIfNeeded(currentObj);
if (currentSub.Value != null)
{
currentSub.Value.Dispose();
}
if (finalNotify == null)
{
return;
}
var propName = current.Value;
pi = RxApp.getPropertyInfoForProperty(currentObj.GetType(), current.Value);
currentSub.Value = (beforeChange ? finalNotify.Changing : finalNotify.Changed).Where(x => x.PropertyName == propName).Subscribe(x => {
obsCh = new ObservedChange <TSender, TValue>()
{
Sender = origSource,
PropertyName = origPath,
Value = (TValue)pi.GetValue(currentObj, null),
};
subject.OnNext(obsCh);
});
}
