"Turn" Android Development Study notes (a)--first knowledge of Android

For a programmer, "top-down" is one of the most common analytic and problem-solving methods, but it is a simple and effective one. So, apply it to the learning of Android, not to turn their impulses into a blind and overwhelmed.

According to the thought of "Top down", "from whole to local", my basic Learning idea is:

1. From the global start, macro understanding of the Android platform architecture
2. Learn how an Android-based application works
3. Understand the environment and prepare to learn the details in a combination of the following practices
4. According to the platform architecture, from the upper to the lower level, a layer of understanding of its relevant specific content, and through practice to strengthen learning

There are countless books on the market about Android, I refer to the road Heroes recommended "Android app development Secret" and combined with the online information on the Android official website (of course, also included in the SDK offline), URL http. Developer.android.com/index.html

First look at the Android platform architecture, such as:

(1) The top level is the "Application layer": contains some core applications, we develop the application also belongs to this layer, the development language is java. (Android app development is primarily on this floor)

(2) then the "Application framework layer": According to my own understanding, the application framework layer is primarily to encapsulate and modularize the functionality that needs to be called, so that it is easy to reuse and easy for developers to replace. To be blunt, the application framework is actually a packaged class of various ready-made classes. (Android system development is mainly in this layer, modified bug, deep customization)

(3) Next is the "Runtime layer": This layer contains libraries developed by C/S, Java-developed core libraries, and Dalvik virtual machines

(4) The bottom layer is the "Linux kernel layer": The Linux kernel version based on Android is the V2.6,linux kernel layer as well as the abstraction layer between hardware and software, the hardware driver contains, the development language is the C language. (Android Drive development on this floor)

Understanding the above, the development of the Android platform has a very clear concept, that is, Android development mainly includes: application development, system development and drive development, application development and system development mainly use the Java language, and need to have a clear understanding of the application framework and operating principle While driver development requires an understanding of the Linux kernel and the need for C language development capabilities.

From:http://www.cnblogs.com/pickuper/archive/2011/06/11/2078516.html

"Turn" Android Development Study notes (a)--first knowledge of Android