Main Components

Main Components:

The architecture shall allow reusing fragments / services among applications. Also it must facilitate contribution of multiple developers. It should be simple and well documented.

IMC Communications

• Communications with IMC systems is done with the help of the IMCJava library.
• Support for message logging as LSF format.
• All messages received from external systems are typed on reception and forward to an internal Message Bus (based in Otto).

Otto Message Bus

• Communications between Fragments and Activities will use an Otto Message Bus.
• Subscribers of IMC messages should register with the bus and use a @Subscribe annotation.
• Other events are generated by the library like SystemConnected, SystemDisconnected, MainSystemSelected, etc.
• Some components may be providers of events, in which case they should be annotated with @Provider.
• ACCL lib may output some DEBUG/INFO/WARNING/ERROR messages as Strings. These can be caught by developers applications for status checking and debugging.

Settings

• In order to support extensibility, each component should provide its own settings and default values.
• For this we will use a custom annotation @ACCLSetting that can be used to generate programatically a SharedPreferences object. This is in line with what Neptus uses.

Services

• The library should provide the following background services:
  • Communications - Provide communication with the network.
  • Logging - Provide logging of IMC messages in the background.
  • WorldState - Provide access to last known state of external systems.
  • LocalState - Access the state of this Android device. It may differ from Android if using external sensors for orientation / location.

Android Templates

• In order to have consistency among Activities, Fragments and Services, a Template of these Features is provided, which Application's components should extend in order to provide common functionalities and consistency among different applications. This is done in src-examples.
  • AcclActivity:

Keeps track of registered Listenners, allows registering and unregistering.
Simple Load/Removal of Fragments.
Some Android utilites.
Pauses and Resumes [AcclBus](https://github.com/LSTS/accl/blob/master/src/pt/lsts/accl/bus/AcclBus.java) uppon [`onPause()`](http://developer.android.com/reference/android/app/Activity.html#onPause()) and [`onResume()`](http://developer.android.com/reference/android/app/Activity.html#onResume()) Calls.

• AcclFragment:

Stores the [View](http://developer.android.com/reference/android/view/View.html) to be searchable for sub components.
Provides access to its Activity's Android Utilities methods.

• AcclService:

Provides a simples start method.
Auto register itself as listenner on [AcclBus](https://github.com/LSTS/accl/blob/master/src/pt/lsts/accl/bus/AcclBus.java).
Services that extend this can start Subscribing to IMCMessages right away with the `@Subscribe` annotation.