Android Application Component
- Asynchronous Message
- Activities, services, and broadcast receivers are activated by asynchronous messages called intents.
- intent
- asynchronous messages/an abstract description of an operation to be performed
- Intent object
- holds the content of the message
- Component name
- Action
- Data
- The URI of the data to be acted on and the MIME type of that data
- Category
- activating
- activity
- Context.startActivity()
- Activity.startActivityForResult()
- service
- Context.startService()
- Context.bindService()
- broadcast receiver
- Context.sendBroadcast()
- Context.sendOrderedBroadcast()
- Context.sendStickyBroadcast()
- activity
- intent resolution
- action
- data (both URI and data type)
- category
- IntentFilter
- Action test
- Intent object must match one of the actions listed in the filter
- Category test
- an Intent object with no categories should always pass this test
- implicit intents contained at least one category: android.intent.category.DEFAULT
- Data test
- URI
- scheme://host:port/path
- When the URI in an Intent object is compared to a URI specification in a filter, it's compared only to the parts of the URI actually mentioned in the filter
- type
- URI
- Action test
- Activity
- a visual user interface
- Activity class
- Activity vs. Window
- Each activity is given a default window to draw in
- An activity can also make use of additional windows
- activity stack
- Service
- doesn't have a visual user interface, but rather runs in the background for an indefinite period of time
- Implementing a Download Background Service
- Broadcast Receiver
- receive and react to broadcast announcements
- Content Provider
- a specific set of the application's data
- Content providers are activated when they're targeted by a request from a ContentResolver.
page revision: 3, last edited: 03 Mar 2010 03:27