Android software development is Google Merge in 2005 to establish a high-tech enterprise Android, which was only 22 months, launched a SMS, mobile search, positioning and other business, and the development of Linux-based general platform. Android is founded in the early days of the Andy Rubin named the father of Android.
Google officially announced this operating system on November 5, 2007, PATRICK BRADY in Google I / O speech Anatomy & Physiology of An Android, and proposed Android HAL architectural diagrams. HAL exists in the form of * .so file, you can separate Android Framework with Linux Kernel. Android has a powerful API, excellent documentation, thriving developer community, and does not need to pay for the development or release of payment. With the increasing popularity of mobile devices, no matter what kind of development context, the use of Android software to develop novel mobile apps is an exciting opportunity.
Application Framework Support Components Reuse and Replacement · Dalvik Virtual Machine Dalm The Mobile Device · Internal Integrated Browser This browser is open source webkit engine · Optimized graphics library includes 2D and 3D graphics libraries,
3D graphics library Based on OpenGL ES 1.0 (Hardware Accelerated optional) · # SQLite for structured data storage · Multimedia support includes common audio, video and static impression file formats (such as MPEG4, H.264, MP3, AAC, AMR , JPG, PNG, GIF) · GSM phone (dependencies) · Bluetooth Bluetooth, Edge, 3G, And WiFi (dependent hardware) · Camera, GPS, compass, and accelerometers (depending on hardware) · Rich development environment Including device simulators, debugging tools, memory and performance analysis charts, and Eclipse integration development environment plug-ins.
A great advantage of the Android phone system is its openness and free service. Android is a fully open platform for third-party software. Developers have greater degrees of freedom for their development procedures, and the iPhone's closedness is completely opposite. So Android has gained better organizer, for example: HTC, Samsung, Xiaomi, Motorola, LG, China Mobile, etc., and Android also received a large number of developers, and some Android Development Competitions in China. It is sufficient to prove the hotness of Android.
Architecture overview
First, the application
Android will be released together with a range of core applications, including Email clients, SMS short message programs, calendars, maps, browsers, contact management programs, and more. All applications are written in Java languages.
Second, the application framework
Developers can also fully access the API framework used by the core application. The architecture of the application simplifies the reuse of components; any application can publish its functional blocks and any other application can use the function blocks it publish (not limited to the security restrictions of the frame). Similarly, the application reuse mechanism also enables the user to easily replace the program components.
Third, the library
Android contains some C / C ++ libraries that can be used by different components in the Android system. They provide services to developers via the Android application framework.
Four, Android running library
Android includes a core library that provides most of the functions of the Java programming language core library.
V. Linux kernel
Android's core system service depends on Linux 2.6 kernel, such as security, memory management, process management, network protocol stack, and drive models. The Linux kernel is also an abstraction between the hardware and the software stack.
