Download GEOAWARE APPLICATION ON ANDROID

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Figure 3.1. Android architecture.
classes compiled by a Java language compiler that have been transformed into the .dex
format by the included "dx" tool.
The Dalvik VM relies on the Linux kernel for underlying functionality such as
threading and low-level memory management [9].
3.3 COMPONENT ARCHITECTURE
The five built-in components within the application namely activity, user interface,
location manager, map display and database interact with each other to seamlessly produce a
highly interactive system (see Figure 3.2).
3.3.1 Activity
An Activity represents the presentation layer of an Android application, e.g. a screen
which the user sees. An Android application can have several activities and it can be
switched between them during runtime of the application. Almost all activities interact with
the user, so the Activity class takes care of creating a window in which the user interface (UI)
can be placed with setContentView (View). There are two methods almost all subclasses of
Activity will implement: