Three development types of Android and three development types of android

Three development types of Android and three development types of android

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Android porting and development

The ultimate objective of Android porting development is to develop Android embedded products. From the developer's perspective, this type of development is based on a hardware system and builds an Android software system based on the hardware system. This type of development works at the underlying layer of the Android system. In terms of software systems, the main focus is on the following two aspects:

• Related device drivers in Linux
  The driver is an interface between hardware and upper-layer software. In the Android mobile phone system, a variety of device drivers such as touch screen, audio, camera, telephone Modem, Wifi, and Bluetooth are required.

• Hardware Abstraction Layer in the Android local framework
  In Android, the hardware abstraction layer works in the user space, between the driver and the Android system. The Android system usually has standard interface definitions for the hardware abstraction layer. during the development process, the implementation of these interfaces provides the Android system with a hardware abstraction layer.

By combining the above two methods, the Android system software has been transplanted. The success or failure of porting depends on the driver quality and understanding of the Android hardware abstraction layer interface.

Android Application Development

• Android applications are developed at the upper layer of the Android system.
• In the Android software system, the interfaces between 3rd levels (Java framework) and 4th levels (Java applications) are Android system interfaces (system APIs ). This level is a standard interface, so Android applications are developed based on this level of interface.

Android System Development

• The functions of the Android system are also being added and improved. Therefore, the development of the Android system is also an important aspect. This type of development also involves all layers of the Android software system.

• A typical example of Android system development is that when the system requires a function, the overall development from the underlying layer to the upper layer is required to provide the called interface for Java-level applications, the procedure is as follows:

• If you need to modify the Android system API, you must be careful, because the system API changes may involve incompatibility of Android applications. in more cases, Android system development only fixes system defects without changing the system API and increases system stability.

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Explanation of Android system principles and development points by2015.2.25 early