Android system adopts a layered
architecture as other operating system. From the chart, the Android structure
is divided into four layers; from the top to the lower layers are the
application layer, system framework layer, runtime layer and the Linux kernel
layer.
Application
Program
Android will be released in conjunction
with a series of core application package together; the application package
includes client, SMS short message program, calendar, map, browser, and
contacts management procedures. All applications are written with the JAVA
language.
The flipbook
builder is an application in your computer to work as the pageflip creator.
Application
Framework
The developers have full access to the API
framework that the core application uses. Architecture design of the
application to simplify the reuse of components; any application can publish
its function blocks and any other applications can use the function block of
the issued. Also, the application of reuse mechanism also enables the user to
replace the assembly convenient.
Hidden in the back of each application and service,
there are a series of systems, including:
Rich and scalable view can be used to build
applications, it includes a list, grid, text box, button, or even embedded web
browser.
Content providers allows applications to
access data in another application (such as contacts database), or to share
their own data
The resource manager providing access to
non - code resources, such as local string, graphics, and layout file.
The notification manager makes the
application can display a custom message in the status bar.
Activity manager used to manage the
application life cycle and provide a common navigation regression function.
System
Library
Android contains C/C++ library, the library
can be used with different component in Android system. They provide services
through the Android application framework for developers. The following are
some of the core library:
* system C Library - an inherited from BSD
standard C system function library of Libc), it is designed specifically for
based on the Embedded Linux device.
* media library - based on the PacketVideo
OpenCORE; the library supports many common audio, video playback and recording,
static image file support. Coding formats including MPEG4, H.264, MP3, AAC,
AMR, JPG, PNG.
* Surface Manager - display subsystem
management, and seamless integration for 2D and 3D layers for multiple
applications.
* LibWebCore - one of the most new web
browser engine, support for the Android browser and an embeddable web view.
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