public static void CallFunction(this MViewModelVariableShareProvider map, VariableChangeEventArgs args)
{
var dmap = table.GetOrCreateValue(map).DelegateMap;
VariableChangeDelegate dg;
if (dmap.TryGetValue(args.Key, out dg))
{
dg(args);
}
}
public async void TestObserver(VariableChangeEventArgs e)
{
await Task.Run(() => System.Threading.Thread.Sleep(1000));
}
/// <summary>
/// Changes the underlying value of the variable under the given context and according to the given value expression.
/// </summary>
/// <param name="context">The context under which the change occurs.</param>
/// <param name="value">The expression representing the value to change the variable to.</param>
/// <param name="ct">The means of extracting the actual value from the expression.</param>
/// <returns>Result of the operation.</returns>
public EvaluationResult ChangeValue(EvaluationContext context, Expression value, ChangeType ct)
{
if (value == null)
{
return(new EvaluationResult(CommonStatusCodes.CvarValueNull, null
, "Null expression passed as value."
, this));
}
var sval = this.StringValue;
var e1 = new VariableChangeEventArgs(context, sval, value);
OnChange(e1);
if (e1.Cancel)
{
return(new EvaluationResult(CommonStatusCodes.InvocationCanceled, null
, e1.CancelReason ?? "Change has stopped."
, this, value, e1));
}
#if HVCE
var e2 = new HostVariableChangeEventArgs(this, context, sval, value);
context.Host.OnChange(e2);
if (e2.Cancel)
{
return(new EvaluationResult(CommonStatusCodes.InvocationCanceled, null
, e2.CancelReason ?? "Change has stopped."
, this, value, e2));
}
#endif
var evalRes = value.Evaluate(context);
if (!evalRes.TruthValue)
{
return(new EvaluationResult(CommonStatusCodes.CvarValueEvaluationFailure, null
, string.Format(CultureInfo.InvariantCulture
, "Evaluation of variable value expression returned non-zero status: {0} ({1})"
, evalRes.Status, evalRes.Output)
, this, value, evalRes));
}
T oldTval = this.Value;
if (ct == ChangeType.FromOutput)
{
try
{
this.StringValue = evalRes.Output;
this.OnChanged(new VariableChangedEventArgs(sval));
return(new EvaluationResult(CommonStatusCodes.Success, null
, evalRes.Output
, this, value, evalRes, oldTval, this.Value));
}
catch (FormatException x)
{
return(new EvaluationResult(CommonStatusCodes.CvarValueFormatInvalid, null
, string.Format(CultureInfo.InvariantCulture
, "Value does not match the format of a {0}."
, typeof(T).Name)
, this, evalRes, x));
}
}
/// <summary>
/// Raisese the <see cref="vCommands.Variables.DelegatedVariable{T}.Change"/> event.
/// </summary>
/// <param name="e">A <see cref="vCommands.EventArguments.VariableChangeEventArgs"/> that contains event data.</param>
protected virtual void OnChange(VariableChangeEventArgs e)
{
this.Change?.Invoke(this, e);
}
/// <summary>
/// Changes the underlying value of the variable under the given context and according to the given value expression.
/// </summary>
/// <param name="context">The context under which the change occurs.</param>
/// <param name="value">The expression representing the value to change the variable to.</param>
/// <param name="ct">The means of extracting the actual value from the expression.</param>
/// <returns>Result of the operation.</returns>
public EvaluationResult ChangeValue(EvaluationContext context, Expression value, ChangeType ct)
{
if (value == null)
{
return(new EvaluationResult(CommonStatusCodes.CvarValueNull, null, "Null expression passed as value.", this.Name));
}
string sval = null;
if (sgetter != null)
{
sval = sgetter();
}
else if (vgetter != null)
{
sval = vgetter().ToString();
}
var e1 = new VariableChangeEventArgs(context, sval, value);
OnChange(e1);
if (e1.Cancel)
{
return(new EvaluationResult(CommonStatusCodes.InvocationCanceled, null, e1.CancelReason ?? "Change has stopped."));
}
#if HVCE
var e2 = new HostVariableChangeEventArgs(this, context, sval, value);
context.Host.OnChange(e2);
if (e2.Cancel)
{
return(new EvaluationResult(CommonStatusCodes.InvocationCanceled, null, e2.CancelReason ?? "Change has stopped."));
}
#endif
var evalRes = value.Evaluate(context);
if (!evalRes.TruthValue)
{
return(new EvaluationResult(CommonStatusCodes.CvarValueEvaluationFailure, null
, string.Format(CultureInfo.InvariantCulture
, "Evaluation of variable value expression returned non-zero status: {0} ({1})"
, evalRes.Status, evalRes.Output)));
}
if (ssetter == null)
{
if (vsetter == null)
{
return(new EvaluationResult(CommonStatusCodes.CvarUnchangeable, null
, "Variable cannot be written."));
}
if (ct == ChangeType.FromData || ct == ChangeType.FromDataOrOutput)
{
T val = default(T);
var res2 = evalRes.ExtractUniqueDatum <T>(-1, this.Name, ref val);
if (res2 == null) // Success!
{
vsetter(val);
OnChanged(new VariableChangedEventArgs(sval));
return(new EvaluationResult(CommonStatusCodes.Success, null
, val.ToString()
, this, value, evalRes, val));
}
else if (ct == ChangeType.FromDataOrOutput)
{
vsetter((T)Convert.ChangeType(evalRes.Output, typeof(T), null));
OnChanged(new VariableChangedEventArgs(sval));
return(new EvaluationResult(CommonStatusCodes.Success, null
, evalRes.Output
, this, value, evalRes, val, res2));
}
else
{
return(new EvaluationResult(CommonStatusCodes.CvarValueDataLacking, null
, "Unable to extract data for variable value."
, this, value, evalRes));
}
}
else if (ct == ChangeType.FromOutput)
{
vsetter((T)Convert.ChangeType(evalRes.Output, typeof(T), null));
OnChanged(new VariableChangedEventArgs(sval));
return(new EvaluationResult(CommonStatusCodes.Success, null
, evalRes.Output
, this, value, evalRes));
}
else
{
return(new EvaluationResult(CommonStatusCodes.CvarChangeTypeNotSupported, null
, "Variable does not support falling back from output to data on change."
, this, value, evalRes));
}
}
else if (ssetter(evalRes.Output))
{
this.OnChanged(new VariableChangedEventArgs(sval));
return(new EvaluationResult(CommonStatusCodes.Success, null
, evalRes.Output
, this, value, evalRes));
}
else
{
return(new EvaluationResult(CommonStatusCodes.CvarValueFormatInvalid, null
, "The given value is not of the correct type."
, this, value, evalRes));
}
}
