Objects and Companion Objects

Singleton.

A singleton class is a class that is defined in such a way that only one instance of the class can be created and used everywhere.

A singleton class in Kotlin is a complimentary object class. It can be used on every classes and works with the concept of inheritance.

How to create a singleton Class? Create new class → Select Object.

Example of Singleton class.
ImportantNumbers.kt as an Object class.
After we’ve made the singleton class, we can cast and use it everywhere.
Example of val implementation in another Kotlin class.
Example of fun implementation in another Kotlin class.

Companion Objects.

A companion objects is written within any class. And also, everything that is written inside the companion object will be basically visible to other classes.

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