Notes About API Guides

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Google API Guide的阅读笔记，温故知新！

Introduction

Apps provide multiple entry points
Apps adapt to different devices

  • App Fundamentals
    the Android system implements the principle of least privilege.

    • App Components

      • Activities: single screen with a user interface
      • Sevices: runs in background to perform long-running operations or to perform work for remote processes
      • Content providers: manages a shared set of app data
      • Broadcast receivers: “gateway” to other components

    • Activating Components

      • Activity: startActivity(), startActivityForResult() with Intent
      • Service: startService(), bindService with Intent
      • Broadcast receivers: sendBroadcast(), sendOrderedBroadcast(), sendStickyBroadcast() with Intent
      • Content providers query() on ContentResolver

  • Device Compatibility
    Do not need consider about device compatible(pass the CTS), but consider app compatible.

    • Device features
    • Platform version
    • Screen configuration

  • System Permissions
    A particular permission may be enforced at a number of places during your program’s operation:

    • At the time of a call into the system, to prevent an application from executing certain functions.
    • When starting an activity, to prevent applications from launching activities of other applications.
    • Both sending and receiving broadcasts, to control who can receive your broadcast or who can send a broadcast to you.
    • When accessing and operating on a content provider.
    • Binding to or starting a service.

App Components

  • Intents and Intent Filters
    The primary information contained in an Intent is: Component name, Action, Data, Category, Extras, Flags
    An implicit intent is tested against a filter by comparing the intent to each of the three elements:, ,

  • Activities
    onPause() is the last method that’s guaranteed to be called before the process can be killed—if the system must recover memory in an emergency, then onStop() and onDestroy() might not be called.

    • Fragments
      lifecycle methods: onAttach(), onCreate(), onCreateView(), onActivityCreated(), onStart(), onResume(), onPause(), onStop(), onDestroyView(), onDetroy(), onDetach()
    • Loaders
      LoaderManager + Loader
    • Tasks and Back Stack
      multitasking on Android
    • Overview Screen

  • Services

  • Content Providers
  • App Widets
  • Processes and Threads

App Resources