Click here to Skip to main content
15,893,722 members
Articles / Desktop Programming / XAML

Silverlight Experimental Hacks (SLEX) - EventTrigger, PropertyTrigger, ReactiveTrigger, InvokeMethodAction, StoryBoardAction, etc. for Silverlight

Rate me:
Please Sign up or sign in to vote.
4.81/5 (8 votes)
14 Jan 2010CPOL6 min read 40.9K   241   24  
A set of Silverlight Experimental Hacks (1) A custom implementation of EventTrigger and PropertyTrigger (2) Invoking methods in your view model in MVVM (3) Conditionally invoking triggers and behaviors (4) ReactiveTrigger for exporting your custom events
using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Collections.Generic;
using System.Reflection;
using System.Globalization;
using System.Collections.ObjectModel;
using System.Reflection.Emit;
using System.Threading;

namespace Slex.Lib.Reactive
{
    #region Internal Classes from System.Reactive

    internal class AnonymousDisposable : IDisposable
    {
        // Fields
        private Action dispose;

        // Methods
        public AnonymousDisposable(Action dispose)
        {
            this.dispose = dispose;
        }

        public void Dispose()
        {
            this.dispose();
        }
    }

    internal class AnonymousObservable<T> : IObservable<T>
    {
        // Fields
        private Func<IObserver<T>, IDisposable> subscribe;

        // Methods
        public AnonymousObservable(Func<IObserver<T>, IDisposable> subscribe)
        {
            this.subscribe = subscribe;
        }

        public IDisposable Subscribe(IObserver<T> observer)
        {
            AsyncSubject<IDisposable> signal = new AsyncSubject<IDisposable>();
            var arg = new AutoDetachObserver(observer, signal);
            IDisposable disposable = this.subscribe(arg);
            signal.OnNext(disposable);
            return disposable;
        }

        // Nested Types
        private class AutoDetachObserver : AbstractObserver<T>
        {
            // Fields
            private IObserver<T> observer;
            private IObservable<IDisposable> signal;

            // Methods
            public AutoDetachObserver(IObserver<T> observer, IObservable<IDisposable> signal)
            {
                this.observer = observer;
                this.signal = signal;
            }

            protected override void Completed()
            {
                this.observer.OnCompleted();
                this.signal.Subscribe<IDisposable>(delegate(IDisposable d)
                {
                    d.Dispose();
                });
            }

            protected override void Error(Exception exception)
            {
                this.observer.OnError(exception);
                this.signal.Subscribe<IDisposable>(delegate(IDisposable d)
                {
                    d.Dispose();
                });
            }

            protected override void Next(T value)
            {
                this.observer.OnNext(value);
            }
        }
    }

    internal abstract class AbstractObserver<T> : IObserver<T>
    {
        // Fields
        private bool isStopped;

        // Methods
        public AbstractObserver()
        {
            this.isStopped = false;
        }

        protected abstract void Completed();
        protected abstract void Error(Exception exception);
        protected abstract void Next(T value);
        public void OnCompleted()
        {
            if (!this.isStopped)
            {
                this.isStopped = true;
                this.Completed();
            }
        }

        public void OnError(Exception exception)
        {
            if (!this.isStopped)
            {
                this.isStopped = true;
                this.Error(exception);
            }
        }

        public void OnNext(T value)
        {
            if (!this.isStopped)
            {
                this.Next(value);
            }
        }
    }

    #endregion
}

By viewing downloads associated with this article you agree to the Terms of Service and the article's licence.

If a file you wish to view isn't highlighted, and is a text file (not binary), please let us know and we'll add colourisation support for it.

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


Written By
Architect
India India
Architect, Developer, Speaker | Wannabe GUT inventor & Data Scientist | Microsoft MVP in C#

Comments and Discussions