This module was heavily inspired by eric elliot and his excellent book programming javascript applications. For publishing different type of message there is need of creating different type of publisher. Eventaggregator receives a message sent by publishers. Consider using the eventaggregator to publish an event across modules and when sending a message between business logic code, such as controllers and presenters. Eventagregator sends the messages to the interested subscriber. To support this, prism provides the eventaggregator component that implements a pubsub event mechanism. Eventaggregator is a module that acts as a single source of events for objects that wish to publish andor subscribe to events.
Subscription it class which used to create subscription token. First, in caliburn micro, the eventaggregators publish method requires an instance of a type to be sent. Consider the following code below which publishes the message supplied on a background thread. Eventaggregator gets a list of all subscriber interested messages. In publisher subscriber eventaggregator is woks as hub whose task is to aggregate all publish message and send message to interested subscribers.
This article shows how to publish events and how to subscribe to them using wpf mvvm and prism. Publisher for integer type publisher publisher for string type publisher so the if class want to publish different type of messages it require to consume or create different type of publisher. This is the second part of my post about event aggregator. Publishersubscriber pattern with event delegate and. When a subscriber subscribes to interested message types via eventaggregator the eventaggregator returns a subscription token that is further used by the subscriber to keep track of its subscriptions. Eventaggregator by name one can easily say that it aggregate events. This means there can be multiple publishers that raise the same event and there can be multiple subscribers listening to the same event. Second, subscribing and handling events require the implementation of the ihandle interface, where t is the type of instances that we want to receive. Components in a composite application often need to communicate with other components and services in the application in a loosely coupled way. In sample program itemlistview user control publishes itemsaved event as shown below. Publishersubscriber pattern with eventdelegate and. I am having an issue subscribing to events with the event aggregator that comes as part of the prism framework. To publish an event the publisher needs to invoke ieventaggregator.
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