What is 'Context' on Android?

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南旧
南旧 2020-11-21 04:46

In Android programming, what exactly is a Context class and what is it used for?

I read about it on the developer site, but I am unable to understand it

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  •  有刺的猬
    2020-11-21 05:05

    Context is an "interface" to the global information about an application environment. In practice, Context is actually an abstract class, whose implementation is provided by the Android system.

    It allows access to application-specific resources and classes, as well as up-calls for application-level operations, such as launching activities, broadcasting and receiving intents, etc.

    In the following picture, you can see a hierarchy of classes, where Context is the root class of this hierarchy. In particular, it's worth emphasizing that Activity is a descendant of Context.

    Activity diagram

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