Elation Events

Elation has several facilities to make dealing with browser events simple:

• elation.events.add(domElement, eventTypes, handlerFunc);
• elation.events.remove(domElement, eventTypes, handlerFunc);
• elation.events.fire({element: eventSource, type: eventType, data: ...});

Here is an example of a simple component which listens for click events, performs a task, and then fires its own event when it's done.

    // Example Javascript component
    elation.component.add('test.foo', function() {
      this.numclicks = 0; // simple member variable
      
      this.init = function() {
        // Register event handlers for the DOM element associated with this component
        elation.events.add(this.container, "click", this);
      }
      this.doSomething = function() {
        // Perform some logic, then fire an event to let any listeners know I'm done
        this.numclicks++;
        elation.events.fire({element: this, type: 'fooDidSomething', data: this.numclicks});
      }
      this.click = function(ev) {
        // Handle click events
        this.doSomething();
      }
    }

Bridging Events with Native Apps

If you are developing a native app which loads your website in a UIWebView/android.webkit.WebView/etc, you can bridge events between the webapp and your native app with a small amount of code. Your app tells the webapp which events it wishes to be notified of by injecting some JS code into the WebView:

elation.native.subscribe('eventname1,eventname2');

Whenever a matching event is fired within the UIWebView, it's passed on to the native client. With webkit-based browsers, this is done by loading a URL of the format elation-event:<eventType>/<eventData> which can be captured and handled with a WebView delegate.

iOS

An Objective-C library is provided to make working with bridged Elation events easy. After binding the bridge to a UIWebView and subscribing to the needed events, these events will be passed through the NSNotificationCenter and can be handled anywhere in your app you want to listen for them.

// Objective-C (iOS)
// First init bridge, bind to specified UIWebView, and subscribe to specified events
[[ElationEventBridge defaultBridge] attachWebView:myWebView subscribe:@"user_login,user_logout"]

// Then any class can add notification observers to watch for the "elation-event" notification
@implementation MyClass 
- (id) init {
  [[NSNotificationCenter defaultCenter] addObserver:self
      selector:@selector(handleElationEvent:) 
      name:@"elation-event"];
}
- (void) handleElationEvent:(NSNotification *) notification {
  NSDictionary *event = notification.userInfo;
  if ([event.type isEqualToString:@"user_login"]) {
    NSDictionary *user = event.data;
    ...
  }
}
@end

Android

(TODO - implement event bridge which exposes web events via the Intent system)

Metro

Metro C# apps expose this functionality via window.external.notify(). The subscription process is the same as mentioned above, and then your app can handle ScriptNotify events. See MSDN's documentation for details.