问题描述
我创建ValidatableModelBase类，但遇到了一些麻烦。我需要订阅SourceCache的更改，并将Count集合转换为IObservable bool。我该怎么办？
private readonly SourceCache<ValidationResult,string> _results;
public IObservalbe<bool> IsValid { get; }
public ValidatableModelBase()
{
_results = new SourceCach<ValidationResult,string>(x => x.PropertyName);
//Doesn't work. I think because i dont .Subscribe() to changes?
IsValid = _results.Connect().IsEmpty();
}
upd：
HasErrors = collection.CountChanged.Subscribe(x => {Count = x;});
IsValid = this.WhenAnyValie(x => x.HasErrors).Select(x => x == 0);
解决方法
您可以执行以下操作：
var databasesValid = collectionOfReactiveObjects
.Connect().Count().Select(x => x == 0);
// Then you can convert that IObservable<bool> to a view model
// property declared as ObservableAsPropertyHelper<bool>.
_databasesValid = databasesValid.ToProperty(this,x => x.DatabasesValid);
您需要包括DynamicData.Aggregation名称空间。