What is 'Context' on Android?

As the name suggests, it's the context of current state of the application/object. It lets newly-created objects understand what has been going on. Typically you call it to get information regarding another part of your program (activity and package/application).

You can get the context by invoking getApplicationContext(), getContext(), getBaseContext() or this (when in a class that extends from Context, such as the Application, Activity, Service and IntentService classes).

Typical uses of context:

Creating new objects: Creating new views, adapters, listeners:

TextView tv = new TextView(getContext());
ListAdapter adapter = new SimpleCursorAdapter(getApplicationContext(), ...);

Accessing standard common resources: Services like LAYOUT_INFLATER_SERVICE, SharedPreferences:

context.getSystemService(LAYOUT_INFLATER_SERVICE)
getApplicationContext().getSharedPreferences(name*, *mode);

Accessing components implicitly: Regarding content providers, broadcasts, intent

getApplicationContext().getContentResolver().query(uri, ...);

3 years ago

Context represents environment data that provides access to things such as databases. It provides services like resolving resources, obtaining access to preferences, and so on. Generally, things like Loading a resource, Launching a new activity, Creating views, and obtaining system service, involve context.

3 years ago

The context class in Android is known as an interface to global information about a certain application environment.
It is declared as an abstract class where implementation is offered by the Android Operating System. Context allows access to the application-specific resources and classes and up-calls for the application-level operations like launching activities, receiving intents, broadcasting, etc. Here is an example in which the abstract method getAssets is implemented from the Context class as follows-

@Override

    public AssetManager getAssets() {

        return mBase.getAssets();

    }

where 'mBase' is a fieldset by the constructor to a certain context.
There are several ways of getting context-

getContext()

getBaseContext()

getApplicationContext()

this

3 years ago