Android 應用程式框架

Android的每一個應用運行在一個安全的沙箱中：

1.系統給每個應用一個UserID，設定該ID對該應用的所有檔案有操作許可權。

2.每個應用都會建立一個獨立的VM。

 

There are separate methods for activiting each type of component:

• 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.