標籤：android c style code java a
- 每個app 都有一個自己的 linux 進程；
- 每個進程都在自己的虛擬機器裡執行
- 兩個app 可以跑在一個進程，一個vm裡
- android app 四大組件：activity，content provider, services, broardcast receivers
- Content Resolver 啟用 Content Provider
- You can start an activity (or give it something new to do) by passing an Intent to startActivity() or startActivityForResult() (when you want the activity to return a result).
- You can start a service (or give new instructions to an ongoing service) by passing an Intent to startService(). Or you can bind to the service by passing an Intent to bindService().
- You can initiate a broadcast by passing an Intent to methods like sendBroadcast(), sendOrderedBroadcast(), or sendStickyBroadcast().
- You can perform a query to a content provider by calling query() on a ContentResolver.
From <http://developer.android.com/guide/components/fundamentals.html>
