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Android

Posted by SZE SZE XU
SZE SZE XU
9,759 Points

why do you need a cast before findviewbyid

https://teamtreehouse.com/library/build-a-simple-android-app-2/basic-android-programming/accessing-views-in-code-assigning-variables

I still dont get what is a class and why do you need to put a cast before findviewbyid

1 Answer

Tom Finet
Tom Finet
7,027 Points
Tom Finet
Tom Finet
7,027 Points

A class is just a blueprint for creating objects which defines its properties and behaviours. The method findViewById returns a View. Since most of the time android developers use a child class of the View class, such as a TextView (extends View), we need to cast it to a TextView for example.

Hope this helps and happy coding!