private TiResponse addEventListener(TiRequestParams data)
{
if (!data.ContainsKey("handle"))
{
throw new ReflectionException("\"addEventListener\" request missing \"handle\" param");
}
string handle = (string)data["handle"];
object instance = InstanceRegistry.getInstance(handle);
if (instance == null)
{
throw new ReflectionException("\"addEventListener\" request invalid handle \"" + handle + "\"");
}
if (!data.ContainsKey("name"))
{
throw new ReflectionException("\"addEventListener\" request missing \"name\" param");
}
string eventName = (string)data["name"];
var eventInfo = instance.GetType().GetEvent(eventName);
// create an array of parameters based on the event info
var parameters = eventInfo.EventHandlerType.GetMethod("Invoke").GetParameters().
Select((p, i) => Expression.Parameter(p.ParameterType, "p" + i)).ToArray();
// construct a new array of parameters to the method we are actually going to call
// need to pass in extra information so the Proxy knows which callback to fire
Expression[] pass = new Expression[5];
parameters.CopyTo(pass, 0);
pass[2] = Expression.Constant(eventInfo.Name);
pass[3] = Expression.Constant(handle);
pass[4] = Expression.Constant(InstanceRegistry.getInstance("browser"));
// Get method info of the handler we want to call
MethodInfo methodInfo = this.GetType().GetMethod("eventHandler", BindingFlags.NonPublic | BindingFlags.Instance);
MethodCallExpression methodCall = Expression.Call(Expression.Constant(this), methodInfo, pass);
// Construct a delegate using a lambda expression
// (Object, EventArgs) => dummyHandler(Object, EventArgs, String, String, WebBrowser)
var lambda = Expression.Lambda(
eventInfo.EventHandlerType,
methodCall,
parameters
).Compile();
// Hook the event to the delegate
eventInfo.AddEventHandler(instance, lambda);
// Store the delegate to remove it later
InstanceRegistry.addDelegate(handle + "." + eventName, lambda);
return(null);
}